Very good explanation. Only that remember some people don't even have access to electricity(national grid) or electricity power supply is not constant, the only alternative is to use solar or other methods, and since Peltier is DC, it can easily be connected to batteries with solar pv, without considering much of energy consumptions especially if you get rid of using 3.5kva or 5kva inverter to handle the conventional AC.
Thank you! I understand this issue but I cannot cover all the possible variations in a video. There is no "one solution fits all". Here where I live, I cannot use solar, so I have to rely on the grid, therefore I base my conclusions on this system. Of course being able to directly connect the Peltiers to DC is a big advantage and could potentially introduce some savings, however keeping them cool enough still poses a large challenge.
Nice calculation. But it's better to modify your title of this video. You said it clearly, it isn't we CANNOT, it's just not worth it from an energy efficiency perspective. However, it's hard to deny that there are still user cases where TEC has advantages over transitional measures.
Hi! Thank you! While I partly agree with you, I have no intentions to change the title. The title is a little bit "clickbait", but it is on purpose. More people will actually come and watch it and realize why it is not feasible to build a Peltier-based aircon. There are many fake videos out there on TH-cam where people build lousy, cardboard box "ACs" using Peltier coolers and they are simply misleading and fake. Because of those videos, many people believe that it is possible and they just waste their money on something which will never work (if they replicate those videos). Here, I break down all the details why it is not a good idea to try to build a Peltier-based AC. Furthermore, if you are interested, I backed this theory with some simple experiments: th-cam.com/video/ORMKZ2M7hKg/w-d-xo.html
It is indeed very inefficient for home use, but it works great when sleeping in a tent in the summer. I use a water cooled system I made using 2 peltier modules with one 120 mm fan and an air radiator on the cold side and two 120 mm fans hooked up to a water radiator and a water block on the warm side, there's also a water pump, everything is connected with 8 mm hoses. It's powerd by a li-ion battery I made with 18650 cells. I simply place the warm side outside the tent and it provides cold air throughout the night.
If you can deal with the inefficiency, then sure, it is usable. It is just not feasible on a large scale from an economic perspective. Also, a tent is a limited volume, so a Peltier might be able to catch up with the thermal load there. It is just 1-2 cubic metres, whereas a room can be 20-30 cubic metres of volume. A different order of magnitude. Which two Peltiers do you use? What is the supply voltage? What is the temperature difference between the inside and outside? How cold the cold side goes? If you can share some details, it would be nice, because other people would appreciate these ideas.
Hey im about to make one with 2x50w ones. I have a small room 10m3 do you think it would be okay for a cooler blower? Im not trying to cool the room.down im.just womdering would it provide relief if directly blowing at me when its 35+ degrees? Any imfo you ca provide woupd.help
can you tell us the details of your device how much wh does it use in one night in hot climate tent camping? how big is your tent? do you use it just to cool under your blanket or the whole tent? how hot does the water get?
I respect all these equations, BUT..., I have a fact. I have a house in 320 Sqf inside a ship container, So I setup a split unit 12k btu's and works awesome, but I'm off-grid, so I started trying economic systems. I setup 2 outside boxes insulated with 5 peltier each box with a fan blowing air to inside container with a very nice quiet fan, I'm 2 years without turn my split ac on. Each box with 5 peltier + 2 small fan + 1 medium fan is working with 1 12v/100ah battery. My house still cold sometimes I need turn off. Soooo, for me without calc, math equations I have a nice and economic way for AC with 10 peltiers.
Yes, you just corroborated what I said in the video. It is not _impossible_ to build such a system, but it is not very economical. Just the price of the battery can already buy me a little mobile AC that can have sufficient cooling for this 30 m^2 area. And for the Peltier, we still need the coolers, the cables, box, electronics...etc. So, at the end it will be more expensive. Then, we haven't even mentioned the power consumption. I don't know which Peltier coolers you use, but with proper design, you can have around 700-1000 W cooling power if the cooling of their hot side is properly carried out. But believe me, it is not economic. A normal, compressor-based AC would run for much longer time or at a higher performance using the same power source.
@@CuriousScientist Number one your chart starts at 80°C.!!! If you’re using it for an air conditioner you’re not going to start at 80°C maybe 44°C but not 80°C you need to adjust your temperature radiant down to livable normal human temperatures. Number two what if your power supply is solar panels that work during the day that is the hottest time and that’s when you need it. Your intro doesn’t say That it is not cost-effective, your intro says that it can’t be done. When you’re out in the middle of the desert and there’s no telephone poles for electricity and you’re off the grid you do what you have to do. So you’re looking for the ability to use something with your system.
@@martyguris1056 @Marty Guris Number one, seems like you don't know how to read performance charts and you haven't watched the whole video. Number two, if you are off grid and you are using solar panels, you want to use something efficient. Peltiers are not.
Sure the efficiency is very low in peltier but is very easy and cheap to build. In off grid mode to start the motor of any ac is costly too you need more than a 100ah batt + very large inverter 2000w pure sine and ac is costly too. In my opinion is cheaper to buy a couple pv panels to overcome the efficiency of peltier and run directly from the charge controller
And additionally if is used a water cooling system with radiator for peltier hot side the final temp in this side should be less than 50 and this gives more range to reduce the air temp in cold side.
this stuff is above my knowledge base. maybe for air conditioning it might not work, but it WORKS for a mini refrigerator. i bought one for $38 and it works great, it also has a 12 volt adapter plug for using in a vehicle.
Mini fridge is a small enclosed volume. Once it is cooled, it doesn't require too much power to maintain the temperature. That's why it could work. I even built my own Peltier fridge and published a series of videos on it.
First of all, thank you for this immerse video. I found some issues with your work. Please have mercy if I understood you wrong. 1. The temperaturedifference between the hot side and the roomtemp is a dynamic thing. When you start the system, dT is much lower as 10 hours later, when the object of your desire is colder than before. For my project, I created a linear function for Qc. 2. Peltier-Modules are very inefficient when you let them work at max voltage. If you take a 12715, you should run it at around 6V. Hot side temperature will decrease because you have to transport less heatenergy. 3. Maybe I didn't notice, but you forgot, that the transported heat through the Peltier (Qc) has to be transported through your cooler too. In your example it would mean that the cooler has to transport 225W (P) + 100W (Qc). 4. The maximum dT is defined by how much heatenergy is flowing back in the object that has to be cooled down and Qc. You can't just say that you want a 30K dT and thats it. Your video is really good to understand how peltier-modules work, thank you very much for that. But it has its little imperfections. Please correct me if I'm wrong
To prove my second point: Check the datasheet for the C.O.P. (Coefficient of Performance)(Qc/P) When working with TEC's you want it to be as high as possible
Hi! Let's see the points. 1. Correct, the dT is not a constant. You can aim for a certain dT by adjusting the power fed to the Peltier (here we assume a constant, "infinite" heat reservoir that cools the hot side). This will also determine the Qc. 2. Correct, you should run them at ~50% of their maximum rated current. I preach this basically in all of my videos related to Peltier coolers. This is one of the biggest misconceptions that people think that Peltiers should run at their maximum nominal current. It is wrong because in that scenario, the Joule heating overpowers the Peltier cooling and the device basically heats itself up. I measured this and showed this in many of my videos for 5 or 6 different Peltier coolers. 3. I might not have made it extremely clear but I hoped that my ugly sketch with the W and Qc showed that at the end 100 + 225 W show up on the hot side. Of course, both the pumped heat and the Joule heat have to be dissipated on the hot side. This is what makes them hard to operate. 4. I respectfully disagree, see the first point. Based on the driving power (voltage and current) you can extremely precisely set the cold side temperature which is indirectly the controlling of the dT. If you have a good cooling system on the hot side, you can assume the hot side to be constantly at the same temperature (for example, you have a piece of lab equipment where you can run chilled water through the hot side constantly kept at 15°C). Then you can set the dT to whatever value you want based on the rest of the parameters, and this will also govern the Qc. 5. There is no point 5, but if you like Peltier coolers, I recommend my Peltier-related playlist. I have some (hopefully) interesting experiments there.
@@CuriousScientist Thank you for your answer. I think I get the fourth point now. I was speaking of the dT of the air in the room and the hot side of the Peltier. You mean the cold side - hot side difference. In that case Qc gets zero when dT(hot side - air) reaches dTmax (hot side - cold side of peltier). So I assume I just didnt get your point there, excuse me.
I disagree, in some cases like in most cars, they generate lots of amps from the alternator allowing you to connect Stereo and amplifier systems that consume 1000 watts many times, using a Peltier for AC even when not as efficient is convenient in this situation.
I can draw nearly 4 kW from my outlets, but that does not make the Peltier cooler-based ACs more feasible. If it was so good why not _any_ car manufacturer has done it so far?
@@CuriousScientist the same reason why some cars still use incandescent bulbs, manual windows, and not automatic headlights, in the case of many companies is because elders control the production in others is just because they have nonsense 20 year contracts with manufacturers also because most of the time products are driven by marketing people, not engineers. This comment is based on my experience, e.g. when we were working at ford the manual ractuator was more expensive in bulk than the electric one.
Yes, but there are many aftermarket parts producers. If the idea would be so good, there would already be huge business built on it. Even I would've considered working on these if they were feasible.
If you put links in the comment, TH-cam might have removed it. I checked if it is waiting for approval, but it was not there. I checked Laird and their highest performance cooler is 480 W (AA-480-24-44-00-XX). An AC is about 3-4x of this performance. I checked the price and it is 1367 GBP without VAT... Also without any power supply and so on. I don't see where this is affordable and feasible for normal people.
Interesting, if I knew this earlier my A/C wouldn't work! But I use them to chill water and antifreeze in a reservoir, then pump that through the radiators from an old air conditioner and it works brilliantly. Behind the radiator is a centrifugal fan, and the reservoir seems to stay very cold through the day. I must have done it wrong. It also makes a great chiller/heater for my hydroponic reservoir which I keep covered just for humidity reasons. Guess it depends on how you use it, but I remember the old bottle coolers for pop in stores that were filled with water, then paper labels and plastic bottles came along and they faded out of existence. But the idea is still good, and peltier chips are great for those as long as you can vent out the heat efficiently, the faster the better. Cheaper on the hydro bill too, no pun intended.
I am also curious! I don't want to discourage you, but I have never heard back from anyone after they claimed in the comments that they built a working system. I wonder why. 🤔
@@sudoboat That cannot be the reason in my opinion. Those who have claimed a working system never uploaded any proof on their channel nor they have contacted me with some additional details.
It depends on the design. If you want icy cold peltiers.the peltier's hot side cools on water, make a container that will fit exactly on window type aircon slot on your window with full of water, put a hole that fits the peltiers hot side sink on water, (so no need for radiators or waterpumps). then attach large heat sink on coldside, only 6 peltiers will be powered up and the 12v turbo fan, then make a large tube that the air will pass only throught the heat sinks then attach turbo fan to suck up the air through the tube. No need for cooling fans for the peltiers just pure water. Then put on a room that the water side part is out of the room and the peltier cold tube is In the room. Like window type aircon. I already tested it and runs smoothly and also cold. On a 3x5 sqm room. For larger room make it doubled.
6 Peltiers from which kind? Also, what is the power consumption of the setup? How much water do you use? What happens to the water after running the cooler for several hours, what cools the water? I never doubted the possibility, but the feasibility of the system. What is the initial temperature of the room, and how much you can cool it down? I would like to see some numbers.
Free electricity aircondition setup 1.)6 peltier= Tec 12715 2.)Power supply= -3 solar pannel 400 watts each -1 Solar charger Controller direct DC to peltiers and 12 volt fan 3.)Rectangle water container size of 1hp aircon 4.)water heats about 33-36 degrees celcius 5.)Room temp= 25 degrees celcius with 3-4 persons inside 23 degrees celcium if 1 person only(cold enough)
Nice! Yes, I was assuming that you are using the strongest Peltier, the TEC12715. If my estimation is right, you can get ~4-600 W of cooling power out of them in optimal conditions. Might be enough for a tiny room, but they need a lot of electricity. The electricity is not free, you had to buy the -probably- expensive solar panels and the power supply.
Hi, yes solar panels and batteries are good enough to run, but not as electricity of 1hp aircon, the ampere is lower than 1hp aircon with condenser, peltiers are easy to power up. No need either for inverters. Just series connections of them same as the batteries. 200 ah batteries can run them 24 hours easily.
Unfortunately no. It also depends on the insulating properties of the fridge, so I would assume it is not just a straightforward formula. But if you know the cooling power and the amount of heat to be removed from the system to reach a certain temperature, you can calculate the time needed to perform the cooling. From that, you can change one of the parameters at a time and recalculate everything. If you want quicker cooling, you add more cooling power or you remove some thermal load. If you want to cool more stuff, you add more cooling power or allow more time.....etc. But the above formulas work (as a first iteration) if there is no heat loss. Of course you can account for that as well.
@@wayneo7220 If you want a formula for the time it takes to cool down the room/object, you have to take the Energy of the room and divide it by the cooling Power (Qc - Qin) Qin is the energy flowing back in the system through the insulation and Qc is a linear function from the datasheet (dT as variable in it) that has to be divided by the whole Heatresistance from the air in the room to the outside. Its very difficult and I had to study some weeks, until the practical thing was proving my calculation of it
Great video that does a good job explaining the problems when dealing with HVAC. Watts x 3.412 = BTU's a btu is a measurement of heat capacity to remove from a structure. This BTU equation was really the only thing you left out, the load of the structure requires the AC whatever it is to be sized to handle the load. The load isn't the same for every structure. We look for (in USA) a 20F drop across the coil also known as the delta. AC is more or less designed to drop air temp inside from 20F from outside. Desert areas of the climate are different for obvious reasons. Earlier AC's would run a coil temperature of 40F, now the coil temp in some cases may reach the high 40'sF. It's impractical to drop temp below 37F for air conditioning because it's too cold. If sized properly too cold would give you complaints *it's too cold* A typical room of 120 sq feet may require 9000 BTU or more depending on various factors. That's just one room. The larger the structure the more you need, especially if you live in a climate that requires cooling and it's not just considered a luxury that you use a couple months of the year. The larger traditional compressor & refrigerant designed AC systems for residential max out at near 60,000 BTU's (5 tons of AC as 12,000 BTU's = 1 ton of air conditioning.) I had someone contact me due to some click bait article claiming some major breakthough would solve the AC refrigerant problem. I would rather have a click bait title that proves something rather than just feeding the beast telling people what they want to hear. *Great Job, leave the title of this video as it is*
Hi! Thank you very much for the detailed explanation! Yes, I skipped over the BTU-related terms because I am not really familiar with HVAC. But I can understand watts and conservation of energy, so I stayed on the "physics side" instead. Your explanation is very clear and easy to understand, thank you! I did not know too much about the HVAC-related things such as how much temperature drop we should achieve and so on, so I definitely learned something today! 9000 BUT is quite a lot in watts (2637 W), it makes no sense to try to pump that much heat with Peltier coolers. But it is hard to convince people about this fact. I see some videos having more than 1M views where they claim that they've built a Peltier AC with a single piece of Peltier cooler... I guess it attracts people because it shows, as you said, what they want to hear.
@@CuriousScientist yeah 9000 BTU's is a base line number because many mini split type AC units start at this capacity size. Regular forced air ducted residential based HVAC systems start at 1 Ton (12,000 BTU) and max out at 5 tons (60,000 BTU) The BTU relates to capacity of the system, if sizing isn't considered it won't cool the room let alone the occupants in it. (Window unit could start at around 5000 BTU, which is still significant compared to this tiny peltier device.) To dive deeper there's the necessary air flow needed to pull the heat out of the structure (room or rooms) If doing multiple rooms you then need duct work or additional cooling heads if using a mini split. The air needed per ton of AC is 350 to 400 CFM of air. (CFM = cubic foot per minute). Old rules were to supply 400 CFM of air per ton of cooling capacity. But Todays tech can modify this blower speed, rarely below 350 CFM per ton of cooling capacity for the most part. So a guy like me having done HVAC for past 30 years, looking at these tiny little fans trying to do the work of a modern AC just imagine how much laughing I am doing in my head. Then someone like you comes along -- doesn't even go to the lengths of delving into BTU's or CFM of air and comes to the same conclusion. So I just had to commend you on not falling victim to the gimmick of clicks. I've seen some of the comments here chastising you for litterally telling the truth as ugly as that can be sometimes. *That's how you know it's the truth, it's ugly 9 times out of 10*
One more point of view: The thermal power and the electric power 225W + 100W have to be removed from the hot side. I plan to use TEC for my floor heating only to pump energy in the cellar from warm air to the liquid floor heating.
Yes! I think a lot of people have the misconception that the heat which is removed from the cold side "disappears". This is what I try to emphasize in most of my Peltier related videos that it is very difficult to keep these things cold and "efficient".
Hi, thanks you for all these informations. Was clear in my mind that replacing ac air conditionning with such approach was a crazy/inefficient idea.... but I think in my personal case can be an option. Let's me explain more: I am living solar offgrid. In summer, I got potentially plenty of power (not produced since I have no enough loads for). I got also a system collecting some fresh water extracted from my 20m depht well going to the roof (in a close loop circuit) and thx to a water-air exchanger I can breath in all rooms something around 20 C. I was thinking to decrease this Tc=20C with some peltier modules which can be modulated (in intensity) via a offgrod solar power diverter. (that I have).. For some technical reason I can only use some existing 2.5mm wires to power the peltier module... this is why I was thinking to 24V peltier modules.....
Hi! You're welcome! Yes, you described a very unique case. You have "unlimited" source of "free" energy, and you also have "free" source of cooling. Obviously, if you have "free electricity" from solar panels, then it is more feasible to run these devices. But if you are just an average Joe, like me who lives in a regular apartment and relies on power from the grid and relies on tap water from the pipes, then it would make no sense to use these inefficient devices, especially when you can have an AC with 3-4x better efficiency, thus 3-4x less consumption for the same output. The simplest way for your issue is to use a DC-DC converter to bring down the voltage to a more appropriate level (8-10 V, roughly) and then power the Peltiers individually with that voltage. You can just connect them parallel to the source, you just need to respect the maximum output current. Or, if you have a fixed 24 V DC source, you can connect three or even four _identical_ Peltier coolers in series. Then each Peltier would experience the same voltage which is the source voltage divided by the number of Peltiers in series. For example, you have three identical Peltiers in series, then each would run at 8 V. But it is very important to use similar Peltiers, because if they have different resistances, then they would run at different voltage and the overall current in the circuit would be different which might not be the best for the devices.
@@CuriousScientist Yes maybe a 24V/48V power supply coupled with a DC solid state relay for perltier's module in series can do the job.... Maybe I should look to water-cooled models since probabalty I can plug my close loop water circruit with it.
I am very curious (really!!), so please keep us posted. So far no one came with their results despite the fact that many people left comments about it. Cheers!
I can understand the cost side of a large project such as an AC or heater, and that it would draw a lot of power. But having one or 2 Peltier models and a few small fans, you can easily make a small desk AC or heater depending on the polarity, and can work well as a small thing to have on your desk for comfort if you can't place a heater or ac unit near you. Or just to make a neat little coaster that can chill and heat drinks.
No, the problem is that one or two Peltier coolers don't have the sufficient power to cool the air down even just for a "local AC". I tried it and showed it in one of my videos. There's essentially no difference in the inlet and outlet air temperature in the case of a single-Peltier air cooler. And even that system was really expensive.
Peltier devices alone are incredibly inefficient, however they can be used rather effectively in an indirect evaporative cooler. Using evaporation to cool down water that's then pumped through a radiator, adding a TEC to the loop would further cool down the water at the cost of double the energy consumption. Is it an AC? No, but it can drop ambient temperature by 30F in a small room. Anything larger than that would be unfeasible as increasing the amount of TEC's in the loop decreases the coefficient of performance well below that of an AC unit.
The temperature drop that you gain with the evaporative cooler becomes a "loss" from Peltier's perspective. You basically increase dT by introducing a cold fluid to the cold side. Higher dT would mean lower Qc. I would rather try to use the evaporative cooler to cool down the hot side of the Peltier cooler and then use only the Peltier to cool something. Since the hot side would (ideally) be under ambient temperature, you would not need to create a very large dT, so you can have a larger Qc. But it is still very energy-demanding.
If i want to make a peltier air conditioner for my pickup i prefer installing a second alternator instead of compressor to supply requirement power if even stock power rate doesn't be enough. So it doesn't need piping, R124 and leaking problems,season maintenance and very cheap and simple to make.
Appreciate the video! Working inside the house all year led to the insight that CO2 really builds up. Any insight on how to bring new air into the house (specifically into one room of the house) during all four seasons (especially winter and summer) without wasting the indoor heat (winter) or cool (summer)? A fan doesn't really accomplish that. Also, air exchange systems (HRV/ERV) cost a fortune ($3 K - $5 K) when the idea is to get fresh air into one highly used room rather than the whole house. Thank you.
@@CuriousScientist Thank you very much for the response! Much appreciated that you took the time to reply. Your video saved me a bunch of time in my life. Thanks.
It’s called a window unit. That’s what we use down south there is a control on the window unit that allows you to let in fresh air from the outside. Down here you can Buy them for anywhere from $100-$500. Depending on how fancy you want.
Thankyou for posting this. Hopefully the countless people who claim to have built air conditioning units with Peltiers on TH-cam will view this first. You are correct, you need at least 2kw of cooling power to cool the average room.
Thank you! Unfortunately, I am a bit late and there are hundreds of fake Peltier air conditioners on TH-cam, haha. But, hopefully people will watch this and also accept the fact that Peltier coolers are not good for air conditioning. Have a nice day!
@@CuriousScientist I have tried to educate them that 100 watts of cooling power will not cool a room but they don't seem to listen or understand. I'm an aircon engineer by trade.
Then you know even more than me! The point where most of the people get confused and falsely convinced where they see that the surface of the cold side can go below -10°C or even -20°C with a very simple setup. This creates the false impression that these devices can cool well, since the surface is so cold it is even "producing ice". The only thing that they "forget" (they don't know it, I would say), that when only the surface of the Peltier is cooled, there is only a tiny amount of heat is being moved from the cold side to the hot side. This allows a large DT, so even with a 40-50°C hot side (i.e. not so good cooling) one can easily see the above mentioned sub-zero temperatures. Because of this thing that they see the ice, they cannot accept the fact that this has nothing to do with the real cooling performance when considerable amounts of volumes have to be cooled.
@@CuriousScientist yes, it's the air temperature coming off the cold heat exchanger that matters, or "air off" as we call it in the AC trade. To cool effectively you need to see an air off below 10 degs C.
And the answer is "Linear Control", "Kalman Beaucy" and optimization. And in this case you can use the Peltier device for measuring Temperatur difference for the control input.
Old video, but i have gathered so far, the cooler the hot side, the lower the temperature you can get, but also the more power it can pump. I am currently working on a device that has 12 volt peltiers running at 8 volts, and watercooling the hot side as good as i can with large watercooling loop.
Your description is not entirely precise. There are 2 parameters that you can trade off: Qc, which is the cooling power (how much heat you can pump from the cold side to the hot side) and DT, which is the temperature difference between the cold side and the hot side. The performance charts also use these 2 parameters. And either you increase DT and you have to sacrifice Qc or the other way around, but you can't have high DT and high Qc simultaneously. It does not matter if your hot side is 50°C or 20°C cold, if you maintain the same DT (let's say 30°C), Qc will be also the same, therefore the pumped heat will not differ. On the other hand, if you want to pump a lot of heat and you want to reach low temperatures, then you have to keep the hot side as cold as possible. This also comes from the fact that I always tell (and told above) that the lower the DT, the larger the Qc. But you can clearly see this from the performance chart as well.
the delta T isnt as much of a concern unless using as a generator. To drive the unit and use it as heat pump or AC the efficiency of the device is best at 9amperes and below (by your graph) and the limiting factor to cool a room should be around above freezing temperature so lets say at 4degrees C. This keeps the evaporator from icing over. A window AC that creates 2000watts SI (your example) of cooling is not standard by any means frictional losses in the compressor and fan of the unit are pretty high. For me in the US a old standard designed 5-6K BTU window unit uses around 550watts (115v x 4.6A) 5000BTU/hr equates to about 1500watt (SI) equivalent cooling power/hr...That is the part you missed when doing your math (/hr) I think with 12peltier at 12volts and 9 ampere would be a sweet spot since the devices are cheaper than the power transformer to run at high amps. If the use of the TEG unit and the design of the system we are discussing is built for best life and efficiency it has the capability to go above COP1 where the standard AC unit CANNOT! As well the TEG can act more like a invertor driven variable speed scroll compressor heat pump unit it can be set to pace the needs of the space to be cooled with the right control systems in place. I would start with a set of aluminum tanks that sandwich the TEG units between using quality liquid metal thermal interface materials and high temp silicone around the units so the sides cannot transfer temp to one another.. Step 2 insulate the tanks individually very well with 3 or more inches of foam insulation board. Step 3 mount the tanks high on the wall 5-6feet* and plumb the hot tank outside to a large surface area thin design radiator like used in HVAC condensers mounted above the height of the tanks but on the outside wall at a 30-45degree angle this side we will let thermal stratification do the work to cool the condenser applying our hot tank line into the top most section and the bottom to return to the tank. If a fan is needed later we could ad one but since we over size the condenser by so much i doubt a fan is needed. We install a small tank above that hot side condenser to be our fill point so no air is in the system so it can thermosyphon. Step 4 we install a substantially sized automobile radiator below the height of the cold tank, adding high static pressure fan and shroud to get the best results. Step 4 install controls and thermodisk switches for the fan and the tanks to peltiers transformers which shouldnt cost as much as the content creator said. There are transformers that easily do 12v 9amps maybe even wall warts that can do that load for about 10-25 dollars each. Final product is 12x12x9amp 1300 watts plus our fan wattage of 200watts or so. 1500 total watts drawn from the power source and 1300watts directly to cooling with 0 friction or efficiency losses but 10-20percent transformer losses. Brings our consumption up to 1650watts/hr.. Here is where i cannot help without an example but i would like to assume a cop3 is very possible and heating or cooling versions could be built and operated at sub freezing temps like the new style Heat pumps are doing. So we should have ended up with a 15K+ BTU air conditioner (similar to a 240volt ac window unit) but we are below the standard wattage limit of a common US homes 120-15amp standard receptacles safe zone of 1800watts on 14guage wire.. Unless you opted to use 240v AC to DC transformers which would be slightly more efficient and no where near the circuits limits. I 100% think it is possible and you should too. Downside is all the parts which could possibly live beyond the standard 5 years a window ac lasts as well if a breakage occurs your not going to walmart to but a entire new unit you only need the part that broke. The AC to DC transformer and the high static pressure fan might be annoying sound wise but i dont think any more so that a cheap window ac and since you are in charge of the controls you get to play with fan speed, cycle times, and all that jazz. Replacing a like sized 5-6K BTU/hr ac unit would be even less TEG's but i wanted to show a good example of how much more cooling is possible and still be inside of a standard wall receptacles wattage range. For you guys out there that are creating things never let anyone stop you from trying it for yourself!....
Thanks for the detailed comment! I am still waiting for people to build a proven AC system based on Peltier coolers. If they are so good, why are they not available commercially and why are they not replacing the conventional units?
@@CuriousScientist Not available commercially partly due to being solid state device if built correctly it doesn't fit manufacturers agenda of planned obsolescence and to not be user serviceable. There are projects people show that are functional but everyone wants to give flack because it is set up as small experiment and not as a real world device but fact is there in the experiment that it is feasible. I dont disagree there arent enough large scale experiments and that is due to the costs. The costs are above a traditional AC system in the beginning but since it is solid state and only if done properly the fact it can last a long time and be user repaired the upfront cost is recouped over time. Ii think another issue is over driving the units rather than working inside the efficiency scale each unit has. We wouldnt by a car and run it around at 6K rpm all day long but everyone playing with the TEG does that. Just like i pointed out your model of TEG has a sweet spot around 9amps and i personally would start there 12volt 9amps using pc power supplies at first as a test find the BTU output and scale unit to my needs. This way the TEG is never under stress enough or bleeding cold and hot sides together due to being over driven.
@@CuriousScientist th-cam.com/video/ZDLN_tMxSQA/w-d-xo.html this video is good example for both your argument and mine. this unit shows some potential but there are changes that could be done.. He draws air from nearest the reservoir that is hot and pumps the heat into the test space. We do not know if his space was in a time of day that it is under solar thermal gains. He is running a high static pressure fan on the TEG displacement unit (air-handler side) but there is very very little surface area in the cold side exchanger, this is another major flaw. If you think about traditional air handler it has A-frame coils because the standard radiator design doesnt have enough surface area also. To cool a space we do not need sub freezing temps we need right at freezing and a superior exchange rate so we dont have a saturation issue on hot or cold sides. This video was done on a table top right near a window it could have easily been set up to displace the heat out the window. My point is there are faults to designs and many are only playing around with the idea they are not being serious enough to get a good result. Many use the cheap small tubs of thermal pastes this is another fault there are better products out there and NO they are not all created equal. The transformer he is using there for the TEG's is under 30 dollars and is not capable to send 9amps per TEG this is another fault. The one he uses easily get online is for CCT and other hobby uses and has a pot switch to change the output which he does close to the end but he saturates the units. The TEG prebuilt he has he has not a clue if the water blocks have adonized coating under the block touching the TEG and i venture to guess it is adonized on both sides which would reduce the water blocks effectiveness. All together a good video showing how a whole unit is laid out but for function of said unit has many flaws or issues to be addressed before giving a honest result.
@@CuriousScientist Thx for taking time to discuss this with me. I wish i was financially in position to experiment with things myself but i have to live vicariously through others and share my thoughts only.
@@masterdebater8757 No problem, I like to discuss about this topic, I am really interested in Peltier coolers. I am also limited financially, so that's why I don't scale up my experiments. I have plans for that, but I need to save up some money. Until that, I am trying to perform my little tabletop experiments and draw conclusions from them.
Yes, I also made one, check my videos. :) Fridge is a relatively small volume and with a good insulation, you can focus the cooling power on the load and not on the compensation of the losses. It will eat more power than a regular compressor-based fridge due to the inefficiency of Peltier coolers, but it can work. Much more feasible than an AC. So much more that you can also find commercial products. I saw mini fridge for boats and cars and I also found a wine cooler. Actually I will make a new video on this topic during the upcoming weeks because I have recently received some new parts for this project. Stay tuned!
I'd like to cool the inside of an open cooler and keep microgreens at a certain temperature and humidity. I wonder if this would be a good use of Peltier-based cooling.
Hi! It depends on the volume of the things to be cooled. If it is a small box in your kitchen, you can probably do it. If it is a larger room that you want to cool indirectly, that will be challenging. If you can provide more details, I could try to see if it is feasible. I could at least guesstimate the parameters.
@@CuriousScientist Thanks! I want to cool a medium sized cooler to about 60 degrees Fahrenheit. I'd like to do this in a garage where the temperature will probably get to about 90 degrees in the Summer. I may have an LED grow light above that could possibly generate a significant amount of heat, but if it were a few inches above the cooler, I think most of that heat would get dissipated into the garage instead of the cooler. It would also be great if I could use it to heat the microgreens to 60 degrees in the Winter when temperatures may drop into the 40s. The ideal humidity for growing microgreens is around 50%, which is what the garage is at most of the time.
This seems totally doable. I still need to educate myself on microgreens, but I can see that they are grown in some sort of trays (in fact, my first Google search lead to a 10" x 20" tray). Is this some sort of hydroponic setup where you would like to cool the water to 60°F (15.6°C) or something different? If it is a water bath that you want to cool, that is relatively easy, but the system has to be sized to the task carefully. If you want to cool the surrounding air only, then that will be a bit challenging. Probably some box or tent would be required to provide some kind of insulation. But since we are talking about small volumes, this should be doable.
@@CuriousScientist In some methods, there will be two trays with a little bit of water on the first one. The seeds are in the second tray inserted on top of the first one. However, I think it is better to just cool the air to the height the microgreens will grow since all the water will evaporate. I'm thinking the microgreens will grow 6 to 8 inches (less than a foot). Maybe, there could a separate enclosed container of water (or other liquid or solid) underneath the trays to retain cold temperatures.
Yes thats why most of the youtube videos only use this to just cool a drink or two. Thermoelectric not currently viable for cooling capacity above ~250 Watts .What are your views on Stirling for -80C to -20C cooling ? I think it has potential to replace cascaded vapor compression.
Yes, people try to "misuse" Peltier coolers. It is not impossible, but it is extremely impractical to use them for AC purposes. Regarding the second part of your comment, I honestly have no idea about it. I have never encountered those devices and it would be silly if I would say anything without any knowledge. Sorry!
Thank you for this great video! I was very willing to use peltiers to cool something down but this video really made me realized that they cannot be used to cool down. But unfortunatelly, I had already got 5 peltiers from the past and I do not know what to do with them. I have researched about what to do with peltiers and noticed that the most logical project is making a refrigerator. Or, what else can I do with peltiers? Everyone says that peltiers takes a lot current and spends a lot energy. Then what is the point to manufacture them? I believe that there can be a valid project to use them and that they are not consuming the energy as much as an iron or a toast machine :) Thank in advance and have a great day!
Hi! Peltiers have a huge are of applications. They are often used to cool laser diodes due to the thermal stability that can be achieved with them. They are also used to cool silicon detector of x-ray detectors. And they are also used in other electronics where you want to avoid vibrations for example, since this is a solid state device. For example hobby astrophotographers use Peltiers to cool the ccd of their cameras to decrease the thermal noise.
i was allways taught if u have lots of energy to throw at it it would wrk but like he said just not eco for some people some have lots of batteries and entergy to throw at it i made one for a science far to prove a teacher wrong but it was really challenging i was able to get it -40 on cold side with watercooling it used a ton off entergy 😊 but awesome video and cheers to all
Yes, it is not impossible, but economically not feasible. I could also reach below -45°C temperatures without any particular effort. But reaching very low temperature does not mean that you can cool down anything with it. It is exactly the opposite. There is a tradeoff between the minimum lowest temperature on the cold side and the amount of heat that you can move from the cold side to the hot side. The less heat you move, the less cooling you do.
Personally my interest is on power generation from temperature differences. How much power can be produced? At what cost? And what min/max temperature differences are needed? Does the greater the temperature difference increase the electric power made?
Hi! I never tried power generation, but they are extremely bad at it. Probably just a few watts. Also the issue is that they would need a large temperature gradient for better power output, but on the other hand it is difficult to maintain the difference because heat can escape from one side to the other which deteriorates the efficiency.
I have made an experiment out of candles and ice. But you need so much heat. I almost powered my Xbox controller with it. But, 2 LEDs were enough for me. ☺️
@@CuriousScientist For one the minimum is 6 degrees from what I understand but what I wonder is if you double it too 12 degrees does the power output also double or is there a graphed gradient of electric output per degree of difference? As for keeping a seperation, that actually isn't a problem, you put each side in insulated chambers to keep the constant temperature seperation. Chamber side heat is solar charged and chamber side cold is water cooled. It would also be beneficial to maximize surface area with redesigning the flat seperator into a tube shape that could be utilzed as tubes like a radiator.
Too add the inside of the tube and the outside would have a temperature difference that could have continuous flows and thus produce a countinueous electric current.
I have personally never tried to use them for energy generating because they are very inefficient. Electroboom made a video on his attempt if I remember correctly and he also explained that these are not good for this purpose. It is enough to generate a few Watts maybe, but that's all.
Nicely done, professor! Too many novices don't understand the math involved, so they make dumb mistakes, the biggest one being ignoring the heat that comes off of a Peltier device. Just because you can generate ice on a very tiny spot does not mean you can freeze the entire room with it. By applying basic math, you have shown the folly of almost all of these TH-camrs.
Thank you very much for you positive comment! Yes, it is so simple! Unfortunately, a lot of people still don't believe me, and a lot of people fall for the fake aircon videos. They just get blinded by the ice forming on the surface.
put the heating side outside of the room, make a good insulation and in a tiny room you wil notice the difference, obviously it won't work in a big room and in a shitdip project.
@@idontcareaboutyou7757 Yes, the concept is the separation of the two rooms. However, just the separation will not help. Still, a lot of cooling power is needed (which requires a lot of Peltiers), and a very good cooling of the hot side is also needed. Otherwise, you lose all the cooling performance due to the too hot hot side. You still need that 1-2 kW of cooling power to have a noticeable change, even in a small room.
@@CuriousScientist yes, you did the maths very well, something i'm no good about, but it was very clear to me by the first step that if you don't cool the hot side, the performance will drastically drop, and that's why separation and insulation is crucial, plus the volume of the room. If you consider the cost of the energy for the power to cell and heat sinks (at least one each side) it will never be efficient, and that's why at nowdays we have not a peltier based air cooler on the market. But if you consider the right evironment, for example a car, with a almost free energy generator (alternator/battery) and you make a duct wich brings the cool air in the car, leaving the hot part in the bonnet, being it a tiny space i think you can get a reasonably good fresh air intake, probably not a real A/C, but something making a difference.
It's not about whether it will work or not. It is not impossible to build one, but it is not feasible. You will need a plenty of units, a lot of (adjustable) power supply and it will consume a stupid amount of electricity.
It seems like if you could transfer the heat from the hot side away from the room you are trying to cool then it wouldn't offset and cancel out the cooling of the target room and thus dramatically increase the efficiency of this system. It would be a great system if you had two areas near each other in which you were trying to cool one and simultaneously heat the other. Like say a walk in refrigerator in the winter time when you would need all the other rooms heated besides the refrigerator.
@@willhchrist100 "It seems like", but it does not work like that. Of course, you need to separate the hot and cold parts (like with a split AC or a fridge/freezer), otherwise it won't work. But still, these units simply do not have the efficiency to keep up with the compressor-based ACs. Even though it is not impossible to build one, it is much more expensive than the compressor-based version and not only in the material cost but also in the running cost. Even if you could use the waste heat for something, the cooling part would be still inefficient. Peltiers are not made for these tasks, they have different purposes.
Nicely explained. Peltier technology haven't improved so much since the first devices, let's see in the future, perhaps if someone develop new ideas. Analysis like this helps a lot to clarify the present situation and maybe motivate someone to break this limits
Thank you! I guess, there should be some breakthrough in solid state physics. The current Peltiers are limited by the characteristics of the materials used in them. Maybe if someone comes up with a new material or something. Let's see if these results become obsolete in a few years.
@@CuriousScientist I haven't watched the video yet so I wouldn't know if you talked about this but they are indeed limited by the materials and there is a new technology called ArcTech and it's a peltier module with new materials that are beneficial compared to the old. Thanks for the vid. Going to watch it now!
Hi! Sure, you can increase their C.O.P (coefficient of performance), but for that, you need to decrease the power you run them at. So you will end up needing more Peltier coolers and more complicated cooling because now you have more modules to cool. They are fundamentally inefficient due to how they're built, so it is very hard to noticeably increase their performance.
Solar panel + electric capacitors + electric coverter 4 medium aluminum radiators each radiator have one cooling fan on it + car radiator liquid + big radiator with big fan to cool all system water + all that will work for 12 thermoelectric peltier each one have heat sink on the hot side with small aluminum radiator to let the water walkthrough it in small box that have a fan inside it to push coold air To the wanted area Note : all the radiators should be insulated with exhaust pipe out of the cooled area ☺️
your line across for the 80c change ... will result in approximately 5 watts ... or 5v at 1a ... a valid useful voltage AND current and you should be using a LOGARITHMIC scale for the wattage as it changes exponentially NOT linearly since it is a transistor device it has a base value to overcome BEFORE it will function think a diode curve .... to get it on a straight line it has to be plotted on a log scale ...
I know this is over a year old, but I was wondering if you can revisit this topic, as, I own a cold plate, that can literally freeze a steak, and it's built out of a thermoelectric cooler, and a heat sink. This means, we can get severely cold Temps, and thus, why I thought a small rv ac unit, might be possible from thermoelectric coolers now days. If I'm wrong, please let me know. If they've improved to freeze a steak, one would think that would provide a decent amount of air cooling, no?
A piece of steak is not at all comparable with a room. It is a piece of wet meat in a direct contact with the cooling surface. Also, with Peltiers, being able to make very cold temperatures is not the same as being able to move a lot of heat (i.e. cool down stuff). One of the main principles of a Peltier cooler is based on the trade-off between these exact things. Either you maintain a large temperature gradient between the hot and cold side of the Peltiers or you move large amount of heat between the sides. But not both at the same time.
I think this video confuses efficiency with capability. The displayed peltier cell is clearly capable of transferring around 160W of heat from the cold side to the hot side (less if the cold side is cooler - 100W of heat when the cold side is 20˚C and hot side 50°C). So, it is very clearly capable of functioning as an air conditioner just fine. The problem is that a standard compressor-based air conditioner would use a lot *less* power to transfer the same amount of energy than the peltier cell. Now, 160W transfer is nowhere near the high end of what peltier cells are capable of. Peltier cells capable of 300W of heat transfer exist (those take around 450W of power to do so - very inefficient compared to compressor-based ACs, but still can do the job). There also is a way to bring up the efficiency (although very slightly) by minimizing the time the peltier spends consuming power without transferring heat (when the cold side is too cold) which you can do with a few temperature sensors measuring the hot & cold side temperatures and a microcontroller consuming a few microW on it's own. Compared to a compressor heat pump air conditioner design, a TEC based design will be very space-efficient, which makes it possible to deploy in cases where the former wouldn't be able to fit. TL;DR: Thermoelectric Cells *can* be the basis of an air conditioner and will do everything a standard residential air conditioner does. The only problem is that they'll be very inefficient while doing so. The efficiency can be slightly improved by regulating the power input of the TEC based on hot&cold side temperatures.
Basically that's what I try to say in the video. It is not efficient, therefore not really feasible to use them as AC. I know that they can move so much heat, but at a cost of efficiency. I never said it is impossible to use them at AC, but it is very inefficient. I even have videos proving it with experiments.
@@CuriousScientist I mean, you say you never said it's impossible, yet the title of the video is says you cannot. Also, Efficiency != Feasibility. The process of heat transfer using a TEC is inefficient, and in cases where a compressor AC may be used wasteful. That however doesn't make doing so infeasible.
Have you watched the whole video? I was also referring to those fake Peltier cooler-based AC videos which are on TH-cam and telling that when people try to replicate those, they don't succeed. And I know that efficiency is not the same as feasibility, but when you have something with 5-10%, maybe 15% efficiency, is it really feasible?
@@CuriousScientist well, the TEC-based AC videos I saw had the problem of keeping the "hot" side in the same environment as the "cold" side. If you did the same thing with a compressor AC, you'd have the same exact problem. As for the question of efficiency - keep in mind that ACs in the strict efficiency sense (heat transfered/energy input) are above 100% efficient. The 300W TEC in that sense is about 60-70% efficient.
The main flaw of those videos is not (only) that, but it is the fact that they try to cool with a simple 60 W or 100 W Peltier running at maximum current. Unfortunately, many people gets the false impression of the Peltier coolers because of those videos. BTW, I also test them with the hot side located at the same room (I have no more space), but I don't test how much they can cool down the room, but I measure the difference between the inlet and outlet air temperature. That also reflects the capabilities to some extent.
The power VS temperature difference graph you use is not commonly found on most of the Peltier device. Most of them give Power VS Voltage and COP vs Voltage.
Using Pelletier is a bad idea, unless you address reasons for its inefficiency.. Causes being; 1. One of its functionalities is an unwanted outcome. To wit, while using it as a COOLER, you will have to dissipate heat, absorbed at cold side. 2. It always produces Ohmic / Joule heating, which is also a menace (while working as a cooler) 3. There is always thermal bleeding between cold and hot sides. 4. Cooling area is very limited or otherwise Cost per cooling area is high. The above said 4 reasons make Pelletier horrendously inefficient (as a heat pump) Personally speaking, working on a project which addresses all the 4 reasons inefficiency. Almost completed it.
Thank you, yes, this is an excellent list of the "drawbacks" of Peltier coolers. Maybe not in this video, but in other videos, I also mentioned these, especially point 2 and 3. Those two things really make it inefficient. But, to add to this list, it is also limited by its working principle. The electrons inside the material who "carry the heat" (not a scientifically exact definition, but it is easy to grasp) are not as efficient as the expanding and condensing gas in a regular, compressor-based cooling system. Your project sounds very interesting!
@@CuriousScientist Thank you for the compliment, because of motivation, it carried. Just another point to mention. Everybody cares about cooling down the hot plate only. On dissipating heat from hot side, you get the required cooling on the cold side. But still then, problem persists, Delta T remains the same, so also is the thermal bleeding between plates. The project remedies all the 4 crisis. By the by, there are reasons for inefficiency with Vapour Compression system also.
Could it possibly be used to cool down a 40 gallon plant terrarium? Also, do Peltier devices remove moisture or anything like that? Edit: My best guess is that the cold side could draw moisture in the air. If that is true, would Peltier coolers be bad for very humid environments?
Depends on how low you want to go with the temperature. I have another video where I built a roughly 15 gallon (~60 liter) well insulated cooling box and I could almost reach 0°C (32 F). If you can use more Peltiers than I did, you can do it, since it is a relatively small and enclosed volume. Make sure to check my playlists on my channel and search for "Peltier cooling box". In the future I will build some more Peltier coolers like that so make sure to subscribe! Cheers!
Replying your edit: Humid environment is bad for _unsealed_ Peltiers. The water will enter the crevices and the constant thermal cycling plus water will damage the device. If your Peltier (or the heat sink attached to its cold side) is below the dew point, then the surface will collect the moisture from the air (condensation). If the cold side is under freezing point, it will collect the water (condensation) and the water will freeze on the surface. This ice layer will grow thicker and thicker which will diminish the heat transfer, thus the cooling efficiency between the cold side and its environment.
I realize my comment is a bit late for the video but I did want to mention something. Given that there are operating costs (cost of electricity) 9 amperes would make more sense in the long run for the same cooling (more devices at a lower amperage to provide the same Qc). With that being said, at -30 DT you only use 87% of the power running 9 amps instead of 15 at 15 volts. To make labeling easier Wc = Watt cooling Wp = Watt power 29 devices running 15 volts and 9 amps would produce 2030 Wc while drawing 3915 Wp = 51.85% Wc / Wp 20 devices running at 15 volts and 15 amps would produce 2000 Wc while drawing 4500 Wp = 44.44% Wc / Wp While your initial cost of setting up the system would be greater, assuming fixed electrical costs, over a certain period of time 29x15V9A system would come out on top from a cost perspective. It is still comically far from traditional compressor style AC units like the one mentioned in this video, 2000 Wc while drawing 800 Wp which is 250% Wc / Wp)
It is great that others also contribute with some calculations and show that it makes no sense to use Peltier coolers for air conditioning. Thanks! Let's hope more people will start believing facts instead of random videos with obnoxious background music.
@@CuriousScientist I will preface this with this is my opinion and only that, if we ever figure out fusion and start getting more than a marginal amount of power in return, I would prefer a Peltier AC unit compared to a traditional compressor for 2 reasons, sound and environmental. Obviously this setup will be horrendously outmatched in terms of efficiency but if the only sound I have to deal with is moving air for a traditional window unit, to me that is a win. The quality of life improvement is worth the extra power and again, this is a personal preference and opinion.
Sure, if we had limitless energy available, we could have many cool stuff. Silent cooling is definitely a nice thing, especially if you are surrounded by multiple of those units. Using just a fan instead of using a compressor would definitely decrease the noise. I guess you probably know, but there are Peltier ACs (I never denied their existence), but they are extremely expensive and as you math also shows consume a lot of energy.
@@CuriousScientist As for the energy, it doesn't have to be limitless, just very abundant to the point where the cost of a MWh is comparable to what a KWh is now. The difference between a compressor AC and a Peltier AC would be pennies given we have the equipment necessary to handle the initial spike of amperage. With that being said, from just a math perspective regardless of materials used as radiators, you will never get more cooling out of a Peltier system than what you put in. Its a little different for heating but still inefficient comparatively. Lastly, using a Peltier as a solid state heat engine is possible but here RTGs do far better. Peltier devices are neat but they don't have any applications where they really shine.
@@camtech1679 I agree with the whole text except the last sentence. They are fantastic for cooling solid-state detectors. 10-20 years ago you had to use liquid nitrogen to cool down the Si-Li X-ray detectors in, for example, scanning electron microscopes. These detectors are used to identify chemical elements using their X-ray emitted due to the electron beam hitting them (EDX or EDS). Nowadays, thanks to both the evolution of semiconductors and the Peltier coolers (which are also semiconductors actually), these X-ray detectors are cooled with Peltier coolers. I also know that they are used to cool down laser diodes and maintain their temperature extremely accurately. They have some pretty nice, but also pretty niche applications.
Seems to be an old video but maybe still worth to comment. The temperature difference (and hence heat pumping ability) of a Peltier is proportional to current while the waste heat is proportional to current squared (actually it's worse, as they heat up they also get more resistive). So yes, 225W waste to get 100W of cooling is not worth the effort, but dropping the current to 9A, the waste heat will fall to maybe 60W for 70W of cooling (COP > 1), and dropping this further to around 6A you could get 50W of cooling for 25W input, COP ~2. Now, while 50W doesn't seem like much, if we combined 10 devices we could achieve about 500W of cooling at a moderate cost and COP of 2. Again 500W might not seem like much, but remember that the big reason we need super powerful air conditioners is that we let rooms get really hot and then expect to cool them down very quickly. Once the room is cooled, it often only requires a few hundred watts to maintain the temperature. So we could have these kind of devices running constantly at low power/high COP we could have good overall result. Note also that if only 200W of cooling from the Peltier bank, the COP just keeps gets better and better. The big mistake everyone makes (including in the video) is to push the Peltiers hard. Run them in the 30-50% of spec and they work great.
I keep track of all comments, regardless of the age of the video. No worries! Aren't you the previous person from 2 days ago? The details are suspiciously similar. :) But maybe I am wrong. Dropping the driving power sure increases the COP, it is shown in the datasheet. But, it also increases the number of components needed for the same Qc. I guess there is an "optimal" trade-off between COP and complexity. 500 W might be little when we consider that the room might be not very well insulated. You said "once the room is cooled". Yeah, but if you only have 500 W cooling power available, when will that occur? Could work with very efficiently insulated rooms maybe or where the temperature fluctuates a lot, and during the colder night the system can catch up. There are actually legit systems where you can use your house as a thermal battery and you simply play with the heating/cooling of the house. It is very promising, but it is probably not the Peltier cooler technology that will solve it. My video is not saying that you *should* run the Peltier at max current, rather the opposite, and if you check my other Peltier cooler-related videos, I always advise _against_ running the Peltier coolers at their maximum rated current, and I always explain why (Joule heating (quadratic) overpowers the Peltier cooling (linear)). The video depicts a typical scenario which one can see on TH-cam where people claim that they have built a Peltier AC (typically with 1 single Peltier cooler) and they blast it at max current. So I just simply followed their example. Cheers!
Thanks! I guess like a lot of people I think Peltiers are cool (pun intended?) but frustrating. But I think the solution is more than just quadratic/linear factor, but also the influence of the heat capacity and heat conduction of the components in the system. If modelled correctly I think we can find a lot more benefits, but it's hard math. One challenge for me was a "Butter cooler" which can keep butter 10°C below room temp with no moving parts. I failed many times using trial and error, and eventually decided to model the system, ran the math and found out that two Peltier devices rated at 85W/8.6A in series (on top of each other) run at just 0.5A (about
Peltiers are definitely cool! (Pun intended, too!) They are not easy to operate, but once you figure them out, they can be useful, I totally agree. Unfortunately, as you also see in the other comments, you can not convince people with math and numbers despite the fact that they can tell you exactly what's up. Just because something becomes cold when we run a little current through it, it doesn't mean that it can do anything related to cooling. Some people have a hard time accepting it.
It depends upon what's the heat generated in a peltier? If we take second law of thermodynamics the heat generated cant be more than the cooling generated (primary work done). I can explain it thus if a refrigerator is left in a (small) room with its doors open, it WILL cool the room as the heat generated will be minuscule visavis the cooling generated. I dont know how true its for the peltier. Will the cooling be more??? or is it the heat???
If you leave an open fridge in a room, it would _raise_ the temperature. All the losses from the work being done, which are not transformed into cooling are dissipated as heat. This is why the condenser and the evaporator are isolated in every cooling devices (fridge, freezer, AC..etc). For Peltiers, as they are about 3-4x less efficient, the Joule heat is more emphasized. This is also why the Peltier coolers will show a funny behavior as you increase their current. Above a certain current, typically 60-80% of their max current, the temperature of the Peltier cooler's cold side will increase by further increasing the current because the Joule heating overpowers the Peltier cooling.
This video will answer your question: th-cam.com/video/_F6XFvycpRg/w-d-xo.html But, there is no "if" in efficiency. I mean, it does not depend on the usage, it is still a Peltier cooler, so the system's efficiency will not change.
Running a 12715 on 6A is much more efficient, then you get a COP of about 2 which might be okay depending on the use case. If someone has a very small room it might be a viable option. But ofcourse you'd have to find the devices for a cheaper price. $5 would be way too much.
And that single unit will produce maybe 30-50 Watts of cooling power. Which is only 40-times less than a typical mobile AC's performance. So, yeah, it is not really feasible in an economic manner.
I use a peltier to cool water in a 50L container, then I circulate the water to the crypto mining servers to cool the radiator that I installed at the back of the server. That way, the cold air flowed by the fans of each server is focused only at the back of each server. For the room I just installed an ordinary air conditioner. But indeed if you want the air in the server room to be cold, then the correct thing is that the hot air coming out of each server is directly discharged outside the room using ducting. This way, not only the chips on the server will be cooler, but the room is also much cooler. But there is also a note, the server room should not only use the same cold air for days, because (I don't understand the cause scientifically) in my practical experience, the psu for each server will be easily damaged if the air in the air conditioned room is not circulated regularly with outside air. The result is that the server room cannot be very cold, because we have to deliberately introduce air from outside with a hotter temperature into the server room that we have cooled using ordinary air conditioning.
How many Peltier coolers are used to cool the water, and which type? At what parameters (U, I) are they running? Crypto miners generate rather large amount of heat, so I am just wondering how you cool them. Why do you need Peltier coolers? Would not be enough to just add a radiator to the water tank?
An insulated dog house would be a feasible project in my opinion. I could cool down an insulated box below 10°C, so a dog house could be also doable. But you would need several Peltier coolers and a good cooling for their hot side.
Peltier elements are commonly used in consumer products. For example, they are used in camping, portable coolers, cooling electronic components, mattress pad sleeping systems and small instruments. some uses definitely won't be suited for large use.
@@CuriousScientist I work personally on some form of cooling project related to sleep tech and will implement peltir method for prototyping Would appreciate someone experienced in the technical aspects before the next canton fair(sourcing side) i’ve reached to specialized companies that manufacture industrial chillers and design specific peltier modules for the different use case. some feedback on the technical side of the tech is need to be honest. If you are interested let me know we can talk about it. 👌🏼
Hi there, how about if it was used in a car to support the air conditioner? Car air conditioner stays as is just add the pelier (with heat exchanger and all) with the hot side towards the engine bay and cool side in cabin? Or do you have any other ideas? Car sees 55C climate and in idle the ac pretty much does nothing. I've added an extra fan to the condenser as well and still not cooling enough. No gas leak. Just super hot climate.
Hi! I think it would not help. Especially, if you want to put the hot side in the engine bay which can be very hot. The larger the temperature gradient the Peltier has to maintain the lower the cooling power it can provide. If your 3-4 horsepower (2-3 kW!) AC cannot keep up with the hot climate, the Peltiers will be pretty much useless. Creating the same cooling power with Peltiers would be extremely expensive and complex.
Unfortunately, I am not a car mechanic, so I cannot give you a proper advice. But I guess you need to buy a more powerful AC for the car. Peltiers would not help if the regular AC already struggles.
What if you use another peltier to absorb the heat produced by it and save some electricity produced by it and put some hit sink on the cool side to maintain its cold side
Tnx bro i know this video is about a year ago. Hope u answer that. I have 5m to 5m Room and i make a plan To build an ac with peltier Like 20pic of peltier And its easy to cool it and also the power and the price its done I just wannted to know can 20pic of peltier device make my room cool? ❤😍
Hi! 20x Tec12715 or maybe even slightly smaller units would do the job. But you would need a LOT of cooling for their hot side and you would need a lot of electricity, probably a few kWs. I don't think its feasible or economical.
Excelente video , me gusta mucho cuando la gente expone sus criterios sobre una base lógica , y motiva para que se realicen los experimentos en otros lugares , realizando mediciones y bajo condiciones bien precisas , gracias por su video .
Did look into this a little, and for my plan is to build a sleep pod - so much smaller area. Heat venting will be ducting flow into the loft and onto the bathroom extractor vent. That's the plan. Looked at stacked peltiers, though was looking at large slab of metal between them to buffer things out more (all insulated as well). Oh to have large blocks of copper. What are your thoughts upon cpu heat-sinks with heat pipes? Considering large solid block with 4 of those in-line with fans in middle all in a nice box that has ducting inlet and outlet that goes right outside via loft. So for my plans, less than 4 peltiers and really talking size wise a bed sized fridge. Though re-tasking an old PC case and PSU, will be factor, salvaging as much as possible.
Stacking the Peltiers will drastically decrease the cooling power. I have a video on this with supporting calculations and also a demo. Reaching very cold temperatures on the cold side does not mean that you can cool with them. CPU coolers are good to keep a Peltier cooled, but it depends on the type. And I can already tell you that 4 Peltiers probably won't be enough.
Hi, I am trying to build a personal ac for my study room, i am not trying to cool down the whole room but just my study table as i am planning to use the ac at the wall which is near my table, So it is basically like a split ac format, Inside the indoor unit, there will be a copper tube bended like the evaporator( like in an actual ac), the ends of the copper tube is connected to a flexible pipe which is attached to the outdoor unit, there will be 3 cpu fans to push out the air from the indoor unit towards the user( Cool air), there would be a small net between the fan and the copper tube to reduce moisture content, In the outdoor unit, there will be a well isolated container, with 3 peltier module's cold side facing inside it. there is a submersible water pump which is connected to the end of the pipe from copper tube as i mentioned to create a closed loop- water circulating system, 3 peltier modules( tec-12706) is used to cool down and maintain the temp of water, after reaching the desired temp, 2 of the peltiers cuts off and 1 work continuously for an hour to maintain the achieved temp and switches to the second peltier, and the 1st one cuts off, this is repeated in cycle by an arduino for energy efficiency, and ofc there will be 3 radiators which is made to be used with 12706 module, the cold water from the container circulates through the copper tube which will absorb surrounding heat and carry it away back to the container where the water is cooled down again bcoz of the peltier modules. The cooled air is pushed out by the cpu fans towards the user, the outdoor unit is placed at the window. i am using 2l of water for circulation, i don't which know which peltier module will cool down the water rapidly, I am really confused whether if this setup works to cool down my study area, which peltier module is the best for my project? whether if i should use a 12v 29a power supply to power all of this. I could really use an expert's insight, I am just a 14 yr old boy and is interested in this stuff, i hope that you would understand and give me some advice :)
Hi! Check my relevant videos, I show that these systems are not really good for air conditioning. I have a video on a specific Peltier-based air cooler. Maybe that could be something for us. But if you want to save money and avoid headaches, just forget this approach and buy a proper AC.
@@CuriousScientist i saw that video and yeah it pretty much explains it but my doubt is if it at least provide some level of cooling to the nearest atmosphere
It can blow slightly cold air at you, but it comes with a lot of noise (fan) and cost. I don't remember the exact cost, but I think I spent like $300 on the hardware (Peltier module, 2x360 mm radiators, pumps, 6 fans, power supply...etc). $300 already buys you a small mobile AC that can cool your whole room...
If you run a cooling block on hot and cool side then the cold side water will cool then run the cool water through a evaporator with a fan pulling through the evaporator
@@CuriousScientist hey I hooked up 5 6amp peltier to 2 blocks and ran water through them. The cold side I set up a loop through a computer radiator and after 20 minutes the radiator dropped to 20 degrees F below my room temperature 🌡. The hot side block was just drawing water from my sink since I didn't have another radiator and the hot block water temperature was 110 degrees F. Not bad if using it to blow directly on you at a desk or a very small room.. 1 or I'd would prefer 2 radiators for the hot side with fans cooling them.
Nice! But how about the radiator (I guess you mean heat sink) temperature if you blow air on them constantly? Of course it cools down if there's no airflow, since there is not too much heat transfer, but it would be interesting to see what happens if you generate some airflow through the radiator.
I never said it is impossible, but it is not economically feasible. Check my other videos, it would cost a fortune to assemble a system that can provide acceptable cooling performance.
Couldn't an air cooling unit be made by isolating the two sides properly with appropriate insulation, the hot side making use of heatsink and fan feeding out through a duct similar to how a tumble drier does, while the cold side has a water cooling block attached feeding a tank with a low flow rate pump pushing water from the tank to a loop that is coiled in front of a fan similar to traditional air conditioner units which then feeds back through the water block before passing back into the tank?
Don't look for how it won't work; Look at how to make it work better! In a small space loke a car or small office, this works great if you exhaust the hot air outside.
If the outside temp is 60 degrees Fahrenheit, and the inside of my room is 85 degrees Fahrenheit, I want as many options as possible to cool down my space to a comfortable level. But you might ask, "Why not just put a regular $10 fan in your window, dummy?" To that I answer, have you ever lived in an agriculture/farm based city? Sure, I could put a fan in my window at full blast to cool my room to the pleasant exterior temperature, but my room would smell like decomposing cow diarrhea, burning rubber and vomit as a result. TEC/Peltier cooling has its place, albeit a somewhat niche product for people who live in cities that smell like rotting garbage. Matching the outside temperature is all many people need... but if the outside air smells obscenely foul (for whatever reason), it would be nice to achieve that temperature without pumping in the outside stench to your home/room. TEC/Peltier cooling can achieve that. Our consumer markets are becoming far too constricted nowadays, and nobody is broadly innovating anymore. Everything is being designed for a small subset of people as "universal for all", rather than society as a whole which has a lot more specific and unique needs.
You don't need Peltier for that either. It can be done with regular split AC which circulates the air which inside and does not bring any air from the outside. It does 4, maybe even more times efficient than the Peltier. The Peltier system will cost you more than a market-made AC, believe me. If you just want to match the temperature outside, you can just build a simple heat exchanger. The Peltier is used if you want to cool _below_ the ambient temperature. Then, if you add the Peltier cooling to the equation, a huge amount of extra cooling and energy will be needed. Innovation is there, don't worry. If something is profitable, they make it. This is not profitable at all.
Yeah, that five 6 A Peltiers will barely produce any cooling power, but at least you will need a lot of cooling for their hot side and a very powerful power supply.
I live in 120sq.ft dorm room with two fans, I was initially going to buy a window AC but Air cooler are cheap, small. Also it's kinda illigal to bring AC. I had an idea of using a Peltier for cooling the water to around 18°C or below 20°C, its normally 29°-38°C outside. And I technical have unlimited power (there is no power metre each room there is only one for whole block). Saddly there is no way to get AC facility here so yeah, I have read most of the comments, its not fecal for most of the people but do think fecal for me?, I think I can cool the water to 18°C or lower with 4 Modules? Or is there a more efficient way to cool water? Which is under 150$
Hi! Why would you try to cool down water? How is that related to your room? Sorry, I don't get it. If you have unlimited power, then you can try to assemble some "air cooler", but the budget might be tight. You would need several Peltier coolers (4-8 or even more), heat sinks, pumps, radiators, power supplies...etc. Check my Peltier-related playlist and look for the "Peltier air cooler" video. Then go to my website and check the Parts & Tools page. You'll find all parts there. Maybe within your budget.
@@anno-user So you want to cool water in a reservoir, then you want to use this cold water and circulate it through a radiator so you can make cold air. You can calculate every detail easily and then you can see the power requirements. So, you'll be able to pick the right type and amount of Peltiers and size the system.
Hi! No, it won't change anything. Actually, it will decrease the already bad efficiency because you add another step to the heat transfer. It will not give you any meaningful results.
@@CuriousScientist But the car to be cooled with a radiator, which is hotter than room temperature, and all air coolers that work without Freon operate in this way. The addition is only cooling the water to give more effect.
I don't want to offend you, but based on your comments, you haven't got any clue about the basic physics of cooling. But still, you came here with a question, I answer it, and you still doubt what I say... First of all, watch my videos more carefully. In one of my videos, I discussed this exact thing. Search for ""Enhanced" water cooler". In cars, you cool spontaneously only. What I mean that the car's engine is well above the ambient temperature when it is running, and the water cooler brings it down somewhat but the whole circle is still above ambient (70-90°C easily). The "freon" cooling that you are referring to is a totally different principle. The "freon" (which is in fact not freon, because it is forbidden to use it due to the fact that freon is harmful for the environment) cooling uses a compressor and forces the material to change its phase. This phase transformation absorbs and releases heat and this is how you cool with "freon". This cooling involves a compressor which compresses the gas to help the process. This cooling is "non-spontaneous", and you can go below ambient temperature. In cars, you just circulate the water with a pump to transfer the heat. There is no phase transformation involved. Also, your idea is still unclear. How do you cool the hot side of the Peltier? Furthermore, why would you transfer the heat to the cold side with water? What would happen if the water would freeze? Your system would be screwed. Cooling a heatsink with the cold side of the Peltier is perfectly OK, no need for water. All those videos you see with these solutions are FAKE. If you still have doubts, build the system, upload a video of the system with properly carried out measurements and let me know. :)
@@CuriousScientist I really have no idea about about the basic physics of cooling so I ask you Also, I do not question your answer, but I was hoping that you would open your mind to the questions I think I came to the wrong place thanks
Sure. It is used for cooling semiconductors, for example, Si-Li X-ray detectors or laser diodes. It is also used for maintaining voltage references at a very precise temperature.
You can get 10 peltiers for 50 bucks, 150W each. But the only problem is removing the heat. One big chunk of alluminium heatsink with 5cm long finns could probably be powerfull enough to be able to removing the heat fast and efficient, also, only with fast spinning fan, minimum 120mm. I do have 3 of those 150W ones and when they are connected all together and everythink works all together , i think they could cool down a 30m2 room quite a bit, yes, it is not a much difference but outcomming air have 10 degrees so.. and now you can imagine what 10 of those will do. They are inefficient that's a fact! but who cares, they are not ment to be used as air conditioning devices, they are way more usefull in car fridges, bewerage coolers etc. But with 10x150W you can cool 100% something, not only your beer but also your house. Paired with solar panels, they could be pretty handy because for the split system AC you need a powerfull inverter and i'm telling you, they are not cheap as you think. Almost every regullar 3 or 5kW inverter shuts down when the compressor in the AC kicks in. You need atleast 6kW one ( only if the AC is 1 phase ) and 9kW when is 3 phase. This minimalize impact on the surge current and inverter won't be able to shut down, for the AC you need a huge power gap sometimes unprofitable, the inverter and AC costs 150 times more than 10 peltiers 150W each. You don't need special electronics. Everything you can now buy via alliexpress and you good to go. 1- 10 peltiers 80 bucks including shipping 2- 2 DC DC regulators 30 bucks ( 1 reg. To each 5 peltiers ) 3- temperature sensor with trigger output ( 10-15 bucks ) 4- wires ( lets say 20 bucks or none when you find them ) 5 - maybe reelay or nothing, you will set it up how you like it In the end you will end up with 300-400 bucks AC system when you also add radiators for liquid cooling, pump,clamps, water heat removing blocks, fans, heatsinks, thermal compound, tubing. 400 for all, atleast 10k for the split system and powerfull invertor ( not to mention money for workers ( when you can DIY thats plus ) and also cables, mounting equipement etc..
You are just speculating... "I think", "could probably be", "should"...etc. Have you tried to actually build such a system? Have you read the datasheet? There's no way you can buy 150 W Peltier coolers for so cheap. Also, 150 W is definitely not the cooling power, but the electrical power (current * voltage). Even if you find a Peltier that can do, let's say, 150 W, it can do it when the temperature difference between the hot and cold side is nearly zero. Thus, you barely drop temperature. Also, aluminum heatsinks, at least those you described are definitely not sufficient for a 150 W Peltier... Please redo your math after actually reading the performance charts of the coolers and after actually understanding how they work.
@@CuriousScientist i do understand what they are capable off, the pros and cons etc. I'm electrician engineer so those types of topologies does not make me any frustrated as looking in to the plans for house electroinstallation. This is really simple and you dont need to describe it any further if you know all things behind that peltier. I bought 3 peltiers 150W each, really 12V 12A i measured that and that is almost 150W and yes, they were cheap. I paid roughly 9€ for all those three peltiers including shipping. And yes, they can output a lot of cooling power but in an inefficient way. I'm not a peltier fanboy but they are in some ciurcumstances pretty handy. My gelid tranquillo rev.3 barely cools 1 peltier enough to keep the cold side in -20 degrees range. 150W is divided in to two sections, 1- cooling power and 2- heat producing power. When you connect this peltier to the 12V PSU and you are able to cool the hot side perfectly, the cold side can be -30c . Whole cooling power of the peltier is maybe 40W max, so 110W is produced as heat you need to dissapate somewhere quick and efficiently. If you have 10 of those 150W, the cooling power could be somewhere between 400-500W and heat 1000-1100W
Reaching -30°C does not tell anything. You have a bare, exposed cold side without any thermal load. Of course it will go down to very low temperatures. But that also means that the temperature difference between the cold side and the hot side is maximized, therefore, the heat that can be pumped is minimized, essentially zero (just a few watts). Put another CPU cooler on the cold side to, run the fan and see what your cold side temperature becomes. It will probably won't even reach 10°C. I did these tests already, check the "debunking Peltier air conditioner" video. And that 400-500 W cooling power is about 1/4th-1/5th of the cooling power that you need to cool down a 20m^2 room... It simply does not make any sense to use Peltiers for air conditioning as compared to an AC because they are so inefficient and they need a relatively "complex" construction to operate. You can just buy a "portable AC" and you just need to plug it in and that's all. It is cheaper both to buy it and operate it.
You can justify based on: the components are cheap or salvaged free, you can power it with the solar panels, you don't need refrigerant and since the refrigerant gas is now banned to be sold to the general public you don't need to pay for gas recharge made by a certified person .
My counter argument is the following: First of all the solar panels are expensive. I just quickly Googled them in my country, maybe not the cheapest prices I found, but if I want to buy let's say 1000 W of solar panels, it would cost me 800-1000 USD... at least... You would then need voltage regulators and power management system to feed the correct power to the Peltiers. You cannot just wire the Peltiers and the solar panels directly together. Also, you cannot leave the solar panels unloaded (open circuit condition), so you will always need to match the load with the produced power. Furthermore, where do you put the solar panels and all the electronics? For example, I live in a block of flat and I have no way of placing several square meters of solar panels anywhere. Nowadays ACs run with special refrigerants, they are not banned, not at least here where I live. I can buy them easily in specialized webshops. Do the math and you will see that for price/watts (cooling power), regular AC is much cheaper.
Hello I am just bored on my lunch break with a question. I have a black car with no AC and it gets super hot in the summer. I thought I could make one of these and stick it in the glove box, which is directly below the vent where my car intakes interior air. I do not expect it to blow ice cold like normal AC, not even close, but would it help a little?
Hi! I don't think it could keep up with the summer heat. To build something using Peltiers that would provide something meaningful would be quite costly. Probably a normal car AC would be cheaper.
since Peltier plates run on DC power, one may be able to build this using earthen batteries for bad situations. i imagine that freon would be almost impossible to make, without an understanding in chemistry.
Freon (or the other gases that replace freon) are related to an entirely different cooling process. Solid state (Peltier) vs. phase transformation (gas-to-liquid) use different principles. But unfortunately I have no idea what is an "earthen battery" and how it is relevant for this topic.
@@CuriousScientist earthen batteries are simple batteries that use soil as a medium. assuming an electrolyte is added, power can be acquired this way. i brought this up, because of the fact that the Peltier is a simple to understand system, which can be applied in deep survival situations, where it would be impossible to create chemical refrigerants, and it runs on DC power, so battery banks could run it, instead of AC power, regardless of whether it is for AC or for food cooling.
Now I get it, thanks! Well, yeah, you can run them from batteries, but since they are not the most efficient things on the World, they would need a lot of power. If you can provide enough power to them via batteries, it is OK to use them that way but I don't know anything about the capabilities of the earthen batteries.
@@CuriousScientist i used them in this comment, because they are simple. if someone has produced potash from a fire pit, then one could use this to increase alkalinity, which i image would make for a good electrolyte when everything is damp.
my idea to use small car evaporator and water block with peltier when the water gets cold it cools down the car evaporator and we add a fan to the car evaporator so it pumps cool air
But could you use it in a ocean cooling setup, where air flows over the cooling side with heatsink fins to ensure max air cooling, and the heat side has heatsinks that have constant cold ocean water flowing over. The only issue is the electricity right?
I do not know what is ocean cooling setup. The issue is that the initial investment (buying everything) and the running cost (electricity) is much more expensive than buying and operating a proper, compressor based AC. It is possible to build an air cooler (see my recent video: th-cam.com/video/ZDLN_tMxSQA/w-d-xo.html ). But it is stupid expensive and needs multiple parts, so you will end up having a complex but inefficient system.
@@CuriousScientist but if power is not an issue.. i was thinking of using a bunch of peltier as a dummy load to dump all my excess solar production instead of using a heater.. since I could not sell power to the grid... so I could at least use a bit of cooling especialy during hot summer days a lot of exess power... the power applied to the peltier could be adjusted at realtime depending on the amount of excess production.. peltiers esilly diy'd and no moving parts...
@@genome692002 Yeah, if you have infinite power, the situation is a little bit better. However, don't forget that you still need to ensure proper cooling for the Peltier coolers and ideally, you would also want to regulate the power to them and not only just dump the power on them. It is not only the cost of the electricity but the cost of the parts which make this unfeasible. I made a "model system" and presented it in one of my videos ("Debunking Peltier ACs") and even a small system cost me more than $300... So if you want to scale it up, prepare to pay a lot only for the parts.
@@CuriousScientist i was working on peltier module Ac .2peltiers cool one aluminium water block (which is in between) and 2 water blocks to cool hot side . (2peltiers and 3 water blocks) (water block hotside--peltier--water block cool side--peltier--water block hot side) in sequence. I used 240mm PC radiator one for hot side and one for cold side . peltier used -12715. For power i used 450watt computer smps , and one issue is when i connect both peltiers to 12v , wires get heat up.
The 12715 consumes 15 A at max current. Since the voltage is limited to 12 V due to the PSU, the amperage will be around 12 A, I assume. 24 A (2 Peltiers) is a LOT, of course it heats up the wires. If you power and adjust the Peltiers properly, you will get around 200-250 W of cooling power. That won't be enough for an AC. Also, why would you transfer the heat with water to the cold side? The cold side should be _as close as possible_ to the object that you want to cool. So in this case, you should put a huge heatsink with a fan on it.
He curious. What about using Nicola Tesla's "cold electricity" to move hot to cold and vice versa. Possible? Would certain unique coil designs provide efficient air conditioning, theoretically?
18:07 because air is not good at picking up temperatures from solid state object especially when on high flow. How can this be mitigated? I have few ideas but wondering if it will truly solve the issue. Convection isn’t enough indeed And if you do force convection you run into noise problems
There is no such thing as "picking up temperature". It is called heat transfer. Even if we use your phrasing, air is not "picking up temperature", but it is "shedding off temperature", since it is warmer than the cooler inside an AC.
@@CuriousScientist I am no engineer and the terms are meant to deliver the idea. “Picking” is used do describe the event where the room air will be forced inside a box that is cooled in order to be quickly cooled before getting exhausted into targeted area. I hope that clarified my meaning
If you look at Peltier chips like speakers that you can run efficiently you’ll be OK,,, If you wanted 1000 W speaker. It would sound better if you had 10 speakers pushing 100 W each and it would be more efficient on heat. The speakers at 100Watt you could play 24 hours versus one speaker at one ohm playing 1000 Watt would be extremely extremely hot. You could maybe play two songs then you would have to let the voice coils rest/cool down . Simple Ten Speakers is more inches of sound = 100 inches. 10 inches reproducing 1000 w is less speaker surface area reproducing sound. Same with the 😊peltier chips, You wouldn’t want to try to produce 400 W of cooling on four peltier chips( I mean it’s OK). But like the RMS level of a speaker, peltier I would think have an RMS level also/ efficiency level also, just like the 10 speaker I explained above, more speaker surface area produces more = better sound I would think more peltier surface area at lower power would produce more better cold 🤷🏽. They’re basically telling you the range and count at which you play your speaker /Peltier chip depends on efficiency /heat and longevity ie sound performance /cold performance since its a peltier not a speaker . ✌🏽
They are very special applications. I'm not saying it is impossible, I am saying it is not economically viable. You need a lot of parts and it will consume a lot of energy. Check their price and energy consumption. The example I am focusing on here is mainly those fake Peltier ACs, which are promoted by several uneducated video creators on TH-cam.
If it is soooo inefficient, why are still being used then??...and why do you have links to buy them on your description? I wouldn´t send people to buy something that doesn´t work. I plan to build a water cooler using Peltier modules: this cold water will circulate on a spiral coil to cool the air from a fan, and into a small confined, thermally insulated space like 7 or 8 cubic meters. It´s not obviously an entire room, and I plan to use solar panels and a 20 Ah battery for this, during the hottest hours of the day in my country there is plenty of sun to run this and more. Using the thermal mass of the water volume and a styrofoam cooler will allow me to get a consistent decrease in the temperature, hopefully. The main issue, I think, is running the Peltier module intermittently. This way you avoid the severe contraction/expansion effect, and the circulating water in the meanwhile will be cooled by the cold side, until a limit is achieved. Regarding the excess heat, it will be properly dissipated TO THE OUTSIDE, and not to the very same space that those TH-camrs you mention are trying to cool down!!! A DT of 30 Celsius is A LOT for practical effects. I don´t know why you choose such a high delta. The video is too long, also, I think. It´s all about WHAT THE COOLING NEEDS ARE, and how you achieve it. I have the strong feeling that conventional cooling equipment based on gas expansion is going to be outdated in the near future. Oh and by the way, the initial testing will be with a couple of modules recycled from old cooling equipment :) I will upload it to my channel in the coming next few weeks.
If people still want to buy Peltier coolers for other experiments, or if they just don't believe me and want to build an AC using Peltier coolers, they can find a quick way to buy them. It is a win-win, and no one is forced to use my links. In fact, there are very small number of people who buy stuff using my links anyway. :) And Peltier coolers have their own specific application field, but that field is not air conditioning. They are for example used to cool silicon drift detectors in analytical instruments or CCD/CMOS detectors in cameras. They don't dissipate too much heat, but they need to be operated at really low temperatures, so Peltier cooling is perfect for this application. Depending on how much water you want to cool, how fast, and how cold, it can work. There are Peltier-based water chillers for fish tanks. It is obviously not the most efficient way, but if you have solar power already available, it might make things cheaper. You should know that the thermal mass works "both way": It will also take a lot of energy to cool the water. I would run the Peltier continuously, but with continuously regulated current. The closer you get to the target temperature, the lower the power you feed to the cooler. 30°C DT is not a lot. You need a proper cooling to maintain a room temperature hot side, in fact, for a room temperature hot side, you need really cold water cooling... The real hot side temperature which actually determines the final numbers in the equations is not the temperature you measure in the heatsink attached to the hot side. Don't forget that there are electrical junctions _UNDER_ the ceramic plate that covers the hot side of the Peltier cooler. The real hot side temperature should be measured there. So, this 30°C assumes that your hot side is about 50°C and and the cold side is 20°C. I did several measurements where I used other parameters to express the real hot side temperature and I usually got an extra 20-30°C as compared to the temperature of the water in the cooling block. If the video is long, skip it, simple. I provide the information that I think I find interesting to share. It is not mandatory to watch each second of it. Conventional gas based cooling will be with us for many-many years. Mark my words. Looking forward to seeing your experiments.
They are used for cooling silicon drift detectors which are used for detecting X-ray. They are also used for cooling CCDs to decrease the thermal noise. Astrophotographers sometimes mod their DSLR camera and add Peltier cooling to cool the CCD and increase the image quality. They are also used to cool laser diodes. So, it is mainly used to cool some sort of semiconductor part where there is not too much dissipated heat, but you need very low temperatures. I use one of those X-ray detectors that I mentioned during my daily job and I know that the detector inside it is at -52°C.
@Curious Scientist im very bad at math, so how many peltiers is needed to match a 0.5hp AC? Lets say tec1-12706 is what im going to use, how many of that is needed to work like a 0.5hp AC?
I can't find that comment either, but I am reading the comments from my phone right now, so it is more difficult. If I am not wrong, the 0.5 HP is for the electrical performance (consumption). Let's say, for the sake of simplicity: 400 W. Usually, the cooling power is about twice as much in a compressor-based AC. A TEC12706 in some arbitrary conditions can provide 30-40 W of cooling power. So, ~20 pieces would be sufficient. But this is a very "hand-waving" calculation.
I don't think anyone is really looking to cool a whole house. I am just looking to use it the cool down the water in my aquaponics water, and lately a 5 X 5' X 5' greenhouse on solar with it. would that be possible?
This video is mainly a response for those fake videos where they claim to build an AC using one single Peltier cooler with some dodgy cooling. Also it is a detailed explanation of the inefficiency of Peltier coolers and why it is not good to use them in AC applications. For the water, you can try to estimate the power you need by calculating the heat needed to cool down a certain volume of water by a certain degrees. Use the Q = c * m * dT formula to see how much heat you need to pump out from your system. Then you can compare this heat/power with the cooling power of the Peltier cooler(s) you want to use. I have some videos on cooling/freezing water with a different types of Peltier coolers. That can give you an idea about the numbers. Also I explain all the calculations and everything in those videos.
i see some errors here. 1. your power consumption is 225w and you pump 100w of heat. your hot side produces 325w, not 225w. 2. you may have disregarded the effect of delta on voltage. you seem to have assumed 15a needs 15v no matter the delta. 3. 30 degrees of delta could be distributed to multiple modules by stacking them. this would increase the module cost but along with efficiency thus reduce the other costs. 5. you disregarded the effect of voltage on efficiency. looking at the datasheet, i can see that if i run it at 2v COP is 4 for 10c delta. with this COP i can even stack two identical modules to achieve 20c delta, which i think is good enough. Qc comes down to 15w though, considering the COP that is less than 20w to dissipate. we will be able cut down on other equipment but still pay more. The twist is this seems more efficient than compressor based cooling. Idk in a couple of decades i will be even :)) 6. dude you can't just say 20cm x 16cm is large and then call an ac unit small. not cool. all aside i like peltier because it's low maintenance with no moving parts or high pressure components, special fluids etc.
Hi! 1. You are correct, I mistakenly forgot to add that extra term. But that just makes everything even worse if you add it, because then more heat has to be removed. 2. That's why it is called assumption. 3. Yes, you can stack them, but as you also said, that would increase the initial cost. Instead of buying let's say ten units, you have to buy 20. 20 TEC12715 would cost you about 200-220 EUR... And this is just the cost of the Peltier coolers, nothing else. 4. You skipped 4. 5. I did not disregard it, but did not consider it. Mainly because of point 3. 15 W will not have any noticeable cooling effect. You need about 50x more to make it comparable with a small AC. Now do the math, it is expensive again from the beginning. 6. 20 cm x 16 cm just the surface area of the Peltiers. Then you need all the auxiliary stuff such as coolers, wiring, power supply...etc.
@@CuriousScientist 3. i was also totally wrong about stacking. it's not more efficient. the pumped heat has to be pumped by the next one too. so one unit of pumped heat causes two modules' cost. 5. i did the math and boy it costs like three times as much :)) 6. i didn't realize this was you. i know your videos you know your stuff. i would doubt myself a bit more if i realized.
Yea its not worth it on cost of electricity alone even if you get all peltiers, power supplys, heatsinks for free in 2years you will spend more on electricty than new ac+costs
Yes! But you have to be very lucky to receive all that expensive stuff for free. :) In my comparison, as we could see it, the Peltier device cost more already in the beginning and the difference between the money spent will just increase if you start using them in the same way, as the Peltier-based cooler would consume roughly 3x more power... As I said, it is not impossible to build it, but it is impractical and expensive.
@@CuriousScientist lucky me then, got a ton of tdk lambda ps supplys (300-1500w) water cooling plates and pumps and fans from work. but yea its probably not worth it anyway.
You can try, but I am still saying that it does not worth the effort. I always try to emphasize that it is not impossible, but it is not practical. It will be extremely expensive to run it over a long period of time. If you start from zero parts, compressor-based AC is much cheaper to buy it and also to run it.
@@CuriousScientist yea i know. How ever i am so tempted to do another project. Have a summer place near the sea, would be fun to see if you could just circulate a close loop or open with sea water and just circulate it.
What if you use it to cool a small fin radiator(directly attaching it to the radiator instead of a heatsink).. then flow water through that radiator and use a fan to blow the cool air?
@@CuriousScientist you explain everything very well, and I subscribed, but what if you hooked up the peltier directly to the radiator.. you skip a lot of those steps.. you explained there are a lot of unnecessary stuff!.. tey to cool the radiator with the peltier while water is running through it.
@@B18bVtec And where exactly would you place it on the radiator? There are not flat surfaces on the radiator to mount the Peltiers. Also, radiators are for liquids. If you want to mount the Peltiers on something, there are heatsinks for that.
@@CuriousScientist it would be mounted closest to the inlet of the hot water... So basically this is the configuration.. a tank with water pumps the water to the radiator.. the inlet of the radiator is being cooled so that the water can get cold before returning to the pump.. then a fan is attached to the radiator to blow the cold air.. similar hot water heaters under the sink.. water comes into a radiator(or a coiled water system) which then gets heated.. and exits hot water.
You are a real person. These NPCs defending an inneficient tech that doesn't have any prsctical use inside earth are just annoying. We must seek efficiency. Pay a little bit more upfront now, or pay the consecuences the rest ofnyour life.
I would not say that Peltier coolers have no practical use at all, but they are definitely useless as an AC. However, I will keep fighting those NPCs. 😄
It depends on how fast and how cold you want to go. I have a project where I built a little fridge using Peltier coolers, check it, and use it as a reference.
@@CuriousScientist It has to go from 32ºC to 20 (extreme case) don´t need to be fast, I am going to assembly the project this week, if you wanna see I can show you. By the way I was reading an artile where someone used a PID controller to control the peltier and god better results in speed of cooling, it would be a good video for you channel I think, if you wanna see : Thermal investigation of a thermoelectric cooler based on Arduino and PID control approach
Peltier coolers are made of ceramic materials and semiconductors. They can't turn into ice. :) But to be serious, since I don't know anything about your system, I can only guess. You are not giving enough power to the unit or not cooling the hot side well enough.
@@CuriousScientist but some vlogger here in TH-cam i saw that thier PILTIER turn into ice . My power supply is 15A and the PILTIER MODULE that ive used is 12709 which is only 9A
I am a scientist and not a vlogger. If you use a 15 A power source without any control and if your PSU can provide around 15-18 V, you will run the 9 A unit at the maximum specifications. Therefore the Joule heating will overpower the Peltier effect and you won't have a good cooling effect. Your experience also suggests that you don't cool the hot side properly. So, put a large heat sink with a fan on the hot side and run the Peltier only at 5-6 A. And watch my videos because I explain how these things work and how they should be used.
![The best (cheap) Peltier module [test 2]](/img/n.gif)
Very good explanation. Only that remember some people don't even have access to electricity(national grid) or electricity power supply is not constant, the only alternative is to use solar or other methods, and since Peltier is DC, it can easily be connected to batteries with solar pv, without considering much of energy consumptions especially if you get rid of using 3.5kva or 5kva inverter to handle the conventional AC.
Thank you! I understand this issue but I cannot cover all the possible variations in a video. There is no "one solution fits all". Here where I live, I cannot use solar, so I have to rely on the grid, therefore I base my conclusions on this system. Of course being able to directly connect the Peltiers to DC is a big advantage and could potentially introduce some savings, however keeping them cool enough still poses a large challenge.
Nice calculation. But it's better to modify your title of this video. You said it clearly, it isn't we CANNOT, it's just not worth it from an energy efficiency perspective. However, it's hard to deny that there are still user cases where TEC has advantages over transitional measures.
Hi! Thank you! While I partly agree with you, I have no intentions to change the title. The title is a little bit "clickbait", but it is on purpose. More people will actually come and watch it and realize why it is not feasible to build a Peltier-based aircon. There are many fake videos out there on TH-cam where people build lousy, cardboard box "ACs" using Peltier coolers and they are simply misleading and fake. Because of those videos, many people believe that it is possible and they just waste their money on something which will never work (if they replicate those videos). Here, I break down all the details why it is not a good idea to try to build a Peltier-based AC. Furthermore, if you are interested, I backed this theory with some simple experiments: th-cam.com/video/ORMKZ2M7hKg/w-d-xo.html
It is indeed very inefficient for home use, but it works great when sleeping in a tent in the summer.
I use a water cooled system I made using 2 peltier modules with one 120 mm fan and an air radiator on the cold side and two 120 mm fans hooked up to a water radiator and a water block on the warm side, there's also a water pump, everything is connected with 8 mm hoses. It's powerd by a li-ion battery I made with 18650 cells. I simply place the warm side outside the tent and it provides cold air throughout the night.
If you can deal with the inefficiency, then sure, it is usable. It is just not feasible on a large scale from an economic perspective. Also, a tent is a limited volume, so a Peltier might be able to catch up with the thermal load there. It is just 1-2 cubic metres, whereas a room can be 20-30 cubic metres of volume. A different order of magnitude.
Which two Peltiers do you use? What is the supply voltage? What is the temperature difference between the inside and outside? How cold the cold side goes? If you can share some details, it would be nice, because other people would appreciate these ideas.
Hello can you get back to me, I need to discuss smthg important. Your cooperation would be appreciated.
Hey im about to make one with 2x50w ones. I have a small room 10m3 do you think it would be okay for a cooler blower? Im not trying to cool the room.down im.just womdering would it provide relief if directly blowing at me when its 35+ degrees? Any imfo you ca provide woupd.help
can you tell us the details of your device how much wh does it use in one night in hot climate tent camping? how big is your tent? do you use it just to cool under your blanket or the whole tent? how hot does the water get?
I respect all these equations, BUT..., I have a fact. I have a house in 320 Sqf inside a ship container, So I setup a split unit 12k btu's and works awesome, but I'm off-grid, so I started trying economic systems. I setup 2 outside boxes insulated with 5 peltier each box with a fan blowing air to inside container with a very nice quiet fan, I'm 2 years without turn my split ac on. Each box with 5 peltier + 2 small fan + 1 medium fan is working with 1 12v/100ah battery. My house still cold sometimes I need turn off. Soooo, for me without calc, math equations I have a nice and economic way for AC with 10 peltiers.
Yes, you just corroborated what I said in the video. It is not _impossible_ to build such a system, but it is not very economical. Just the price of the battery can already buy me a little mobile AC that can have sufficient cooling for this 30 m^2 area. And for the Peltier, we still need the coolers, the cables, box, electronics...etc. So, at the end it will be more expensive. Then, we haven't even mentioned the power consumption. I don't know which Peltier coolers you use, but with proper design, you can have around 700-1000 W cooling power if the cooling of their hot side is properly carried out. But believe me, it is not economic. A normal, compressor-based AC would run for much longer time or at a higher performance using the same power source.
@@CuriousScientist Number one your chart starts at 80°C.!!! If you’re using it for an air conditioner you’re not going to start at 80°C maybe 44°C but not 80°C you need to adjust your temperature radiant down to livable normal human temperatures. Number two what if your power supply is solar panels that work during the day that is the hottest time and that’s when you need it. Your intro doesn’t say That it is not cost-effective, your intro says that it can’t be done. When you’re out in the middle of the desert and there’s no telephone poles for electricity and you’re off the grid you do what you have to do. So you’re looking for the ability to use something with your system.
@@martyguris1056 @Marty Guris Number one, seems like you don't know how to read performance charts and you haven't watched the whole video. Number two, if you are off grid and you are using solar panels, you want to use something efficient. Peltiers are not.
Sure the efficiency is very low in peltier but is very easy and cheap to build. In off grid mode to start the motor of any ac is costly too you need more than a 100ah batt + very large inverter 2000w pure sine and ac is costly too. In my opinion is cheaper to buy a couple pv panels to overcome the efficiency of peltier and run directly from the charge controller
And additionally if is used a water cooling system with radiator for peltier hot side the final temp in this side should be less than 50 and this gives more range to reduce the air temp in cold side.
this stuff is above my knowledge base. maybe for air conditioning it might not work, but it WORKS for a mini refrigerator. i bought one for $38 and it works great, it also has a 12 volt adapter plug for using in a vehicle.
Mini fridge is a small enclosed volume. Once it is cooled, it doesn't require too much power to maintain the temperature. That's why it could work. I even built my own Peltier fridge and published a series of videos on it.
First of all, thank you for this immerse video.
I found some issues with your work. Please have mercy if I understood you wrong.
1. The temperaturedifference between the hot side and the roomtemp is a dynamic thing. When you start the system, dT is much lower as 10 hours later, when the object of your desire is colder than before.
For my project, I created a linear function for Qc.
2. Peltier-Modules are very inefficient when you let them work at max voltage. If you take a 12715, you should run it at around 6V. Hot side temperature will decrease because you have to transport less heatenergy.
3. Maybe I didn't notice, but you forgot, that the transported heat through the Peltier (Qc) has to be transported through your cooler too. In your example it would mean that the cooler has to transport 225W (P) + 100W (Qc).
4. The maximum dT is defined by how much heatenergy is flowing back in the object that has to be cooled down and Qc.
You can't just say that you want a 30K dT and thats it.
Your video is really good to understand how peltier-modules work, thank you very much for that. But it has its little imperfections.
Please correct me if I'm wrong
To prove my second point:
Check the datasheet for the C.O.P. (Coefficient of Performance)(Qc/P) When working with TEC's you want it to be as high as possible
Hi! Let's see the points.
1. Correct, the dT is not a constant. You can aim for a certain dT by adjusting the power fed to the Peltier (here we assume a constant, "infinite" heat reservoir that cools the hot side). This will also determine the Qc.
2. Correct, you should run them at ~50% of their maximum rated current. I preach this basically in all of my videos related to Peltier coolers. This is one of the biggest misconceptions that people think that Peltiers should run at their maximum nominal current. It is wrong because in that scenario, the Joule heating overpowers the Peltier cooling and the device basically heats itself up. I measured this and showed this in many of my videos for 5 or 6 different Peltier coolers.
3. I might not have made it extremely clear but I hoped that my ugly sketch with the W and Qc showed that at the end 100 + 225 W show up on the hot side. Of course, both the pumped heat and the Joule heat have to be dissipated on the hot side. This is what makes them hard to operate.
4. I respectfully disagree, see the first point. Based on the driving power (voltage and current) you can extremely precisely set the cold side temperature which is indirectly the controlling of the dT. If you have a good cooling system on the hot side, you can assume the hot side to be constantly at the same temperature (for example, you have a piece of lab equipment where you can run chilled water through the hot side constantly kept at 15°C). Then you can set the dT to whatever value you want based on the rest of the parameters, and this will also govern the Qc.
5. There is no point 5, but if you like Peltier coolers, I recommend my Peltier-related playlist. I have some (hopefully) interesting experiments there.
@@CuriousScientist Thank you for your answer. I think I get the fourth point now. I was speaking of the dT of the air in the room and the hot side of the Peltier. You mean the cold side - hot side difference. In that case Qc gets zero when dT(hot side - air) reaches dTmax (hot side - cold side of peltier).
So I assume I just didnt get your point there, excuse me.
I disagree, in some cases like in most cars, they generate lots of amps from the alternator allowing you to connect Stereo and amplifier systems that consume 1000 watts many times, using a Peltier for AC even when not as efficient is convenient in this situation.
I can draw nearly 4 kW from my outlets, but that does not make the Peltier cooler-based ACs more feasible. If it was so good why not _any_ car manufacturer has done it so far?
@@CuriousScientist the same reason why some cars still use incandescent bulbs, manual windows, and not automatic headlights, in the case of many companies is because elders control the production in others is just because they have nonsense 20 year contracts with manufacturers also because most of the time products are driven by marketing people, not engineers. This comment is based on my experience, e.g. when we were working at ford the manual ractuator was more expensive in bulk than the electric one.
Yes, but there are many aftermarket parts producers. If the idea would be so good, there would already be huge business built on it. Even I would've considered working on these if they were feasible.
@@CuriousScientist mmm seems that my other comment disappeared... anyways EIC TECA and LAIRD are already fabricating some units.
If you put links in the comment, TH-cam might have removed it. I checked if it is waiting for approval, but it was not there. I checked Laird and their highest performance cooler is 480 W (AA-480-24-44-00-XX). An AC is about 3-4x of this performance. I checked the price and it is 1367 GBP without VAT... Also without any power supply and so on. I don't see where this is affordable and feasible for normal people.
Interesting, if I knew this earlier my A/C wouldn't work! But I use them to chill water and antifreeze in a reservoir, then pump that through the radiators from an old air conditioner and it works brilliantly. Behind the radiator is a centrifugal fan, and the reservoir seems to stay very cold through the day. I must have done it wrong. It also makes a great chiller/heater for my hydroponic reservoir which I keep covered just for humidity reasons. Guess it depends on how you use it, but I remember the old bottle coolers for pop in stores that were filled with water, then paper labels and plastic bottles came along and they faded out of existence. But the idea is still good, and peltier chips are great for those as long as you can vent out the heat efficiently, the faster the better. Cheaper on the hydro bill too, no pun intended.
Would be interesting to see your system in action and see the power consumption, the temperatures, the cost calculations...etc. Cheers!
Any updates on performance?
I am also curious! I don't want to discourage you, but I have never heard back from anyone after they claimed in the comments that they built a working system. I wonder why. 🤔
@@CuriousScientist ...because TH-cam commenting system is atrocious?
@@sudoboat That cannot be the reason in my opinion. Those who have claimed a working system never uploaded any proof on their channel nor they have contacted me with some additional details.
It depends on the design. If you want icy cold peltiers.the peltier's hot side cools on water, make a container that will fit exactly on window type aircon slot on your window with full of water, put a hole that fits the peltiers hot side sink on water, (so no need for radiators or waterpumps). then attach large heat sink on coldside, only 6 peltiers will be powered up and the 12v turbo fan, then make a large tube that the air will pass only throught the heat sinks then attach turbo fan to suck up the air through the tube. No need for cooling fans for the peltiers just pure water. Then put on a room that the water side part is out of the room and the peltier cold tube is In the room. Like window type aircon. I already tested it and runs smoothly and also cold. On a 3x5 sqm room. For larger room make it doubled.
6 Peltiers from which kind? Also, what is the power consumption of the setup? How much water do you use? What happens to the water after running the cooler for several hours, what cools the water? I never doubted the possibility, but the feasibility of the system. What is the initial temperature of the room, and how much you can cool it down? I would like to see some numbers.
Free electricity aircondition setup
1.)6 peltier= Tec 12715
2.)Power supply=
-3 solar pannel 400 watts each
-1 Solar charger Controller direct DC to peltiers and 12 volt fan
3.)Rectangle water container size of 1hp aircon
4.)water heats about 33-36 degrees celcius
5.)Room temp=
25 degrees celcius with 3-4 persons inside
23 degrees celcium if 1 person only(cold enough)
Nice! Yes, I was assuming that you are using the strongest Peltier, the TEC12715. If my estimation is right, you can get ~4-600 W of cooling power out of them in optimal conditions. Might be enough for a tiny room, but they need a lot of electricity. The electricity is not free, you had to buy the -probably- expensive solar panels and the power supply.
Hi, yes solar panels and batteries are good enough to run, but not as electricity of 1hp aircon, the ampere is lower than 1hp aircon with condenser, peltiers are easy to power up. No need either for inverters. Just series connections of them same as the batteries. 200 ah batteries can run them 24 hours easily.
Thank you! Very informative.. i wish you have a video on youtube about your setup.. 😅
Finally a great explanation on how to read a performance curve chart, my thanks.
You are welcome!
@@CuriousScientist Do you know of a formula for sizing the wattage of a module to the fridge cubic feet/meter?
Unfortunately no. It also depends on the insulating properties of the fridge, so I would assume it is not just a straightforward formula. But if you know the cooling power and the amount of heat to be removed from the system to reach a certain temperature, you can calculate the time needed to perform the cooling. From that, you can change one of the parameters at a time and recalculate everything. If you want quicker cooling, you add more cooling power or you remove some thermal load. If you want to cool more stuff, you add more cooling power or allow more time.....etc. But the above formulas work (as a first iteration) if there is no heat loss. Of course you can account for that as well.
@@CuriousScientist Thank you for your input, CS.
@@wayneo7220 If you want a formula for the time it takes to cool down the room/object, you have to take the Energy of the room and divide it by the cooling Power (Qc - Qin)
Qin is the energy flowing back in the system through the insulation and Qc is a linear function from the datasheet (dT as variable in it) that has to be divided by the whole Heatresistance from the air in the room to the outside.
Its very difficult and I had to study some weeks, until the practical thing was proving my calculation of it
Great video that does a good job explaining the problems when dealing with HVAC. Watts x 3.412 = BTU's a btu is a measurement of heat capacity to remove from a structure. This BTU equation was really the only thing you left out, the load of the structure requires the AC whatever it is to be sized to handle the load. The load isn't the same for every structure. We look for (in USA) a 20F drop across the coil also known as the delta. AC is more or less designed to drop air temp inside from 20F from outside. Desert areas of the climate are different for obvious reasons. Earlier AC's would run a coil temperature of 40F, now the coil temp in some cases may reach the high 40'sF. It's impractical to drop temp below 37F for air conditioning because it's too cold. If sized properly too cold would give you complaints *it's too cold*
A typical room of 120 sq feet may require 9000 BTU or more depending on various factors. That's just one room. The larger the structure the more you need, especially if you live in a climate that requires cooling and it's not just considered a luxury that you use a couple months of the year. The larger traditional compressor & refrigerant designed AC systems for residential max out at near 60,000 BTU's (5 tons of AC as 12,000 BTU's = 1 ton of air conditioning.)
I had someone contact me due to some click bait article claiming some major breakthough would solve the AC refrigerant problem. I would rather have a click bait title that proves something rather than just feeding the beast telling people what they want to hear. *Great Job, leave the title of this video as it is*
Hi! Thank you very much for the detailed explanation!
Yes, I skipped over the BTU-related terms because I am not really familiar with HVAC. But I can understand watts and conservation of energy, so I stayed on the "physics side" instead.
Your explanation is very clear and easy to understand, thank you! I did not know too much about the HVAC-related things such as how much temperature drop we should achieve and so on, so I definitely learned something today!
9000 BUT is quite a lot in watts (2637 W), it makes no sense to try to pump that much heat with Peltier coolers. But it is hard to convince people about this fact. I see some videos having more than 1M views where they claim that they've built a Peltier AC with a single piece of Peltier cooler... I guess it attracts people because it shows, as you said, what they want to hear.
@@CuriousScientist yeah 9000 BTU's is a base line number because many mini split type AC units start at this capacity size. Regular forced air ducted residential based HVAC systems start at 1 Ton (12,000 BTU) and max out at 5 tons (60,000 BTU) The BTU relates to capacity of the system, if sizing isn't considered it won't cool the room let alone the occupants in it. (Window unit could start at around 5000 BTU, which is still significant compared to this tiny peltier device.)
To dive deeper there's the necessary air flow needed to pull the heat out of the structure (room or rooms) If doing multiple rooms you then need duct work or additional cooling heads if using a mini split. The air needed per ton of AC is 350 to 400 CFM of air. (CFM = cubic foot per minute). Old rules were to supply 400 CFM of air per ton of cooling capacity. But Todays tech can modify this blower speed, rarely below 350 CFM per ton of cooling capacity for the most part.
So a guy like me having done HVAC for past 30 years, looking at these tiny little fans trying to do the work of a modern AC just imagine how much laughing I am doing in my head. Then someone like you comes along -- doesn't even go to the lengths of delving into BTU's or CFM of air and comes to the same conclusion. So I just had to commend you on not falling victim to the gimmick of clicks. I've seen some of the comments here chastising you for litterally telling the truth as ugly as that can be sometimes. *That's how you know it's the truth, it's ugly 9 times out of 10*
One more point of view: The thermal power and the electric power 225W + 100W have to be removed from the hot side.
I plan to use TEC for my floor heating only to pump energy in the cellar from warm air to the liquid floor heating.
Yes! I think a lot of people have the misconception that the heat which is removed from the cold side "disappears". This is what I try to emphasize in most of my Peltier related videos that it is very difficult to keep these things cold and "efficient".
Hi, thanks you for all these informations. Was clear in my mind that replacing ac air conditionning with such approach was a crazy/inefficient idea.... but I think in my personal case can be an option. Let's me explain more: I am living solar offgrid. In summer, I got potentially plenty of power (not produced since I have no enough loads for). I got also a system collecting some fresh water extracted from my 20m depht well going to the roof (in a close loop circuit) and thx to a water-air exchanger I can breath in all rooms something around 20 C. I was thinking to decrease this Tc=20C with some peltier modules which can be modulated (in intensity) via a offgrod solar power diverter. (that I have).. For some technical reason I can only use some existing 2.5mm wires to power the peltier module... this is why I was thinking to 24V peltier modules.....
Hi! You're welcome!
Yes, you described a very unique case. You have "unlimited" source of "free" energy, and you also have "free" source of cooling. Obviously, if you have "free electricity" from solar panels, then it is more feasible to run these devices. But if you are just an average Joe, like me who lives in a regular apartment and relies on power from the grid and relies on tap water from the pipes, then it would make no sense to use these inefficient devices, especially when you can have an AC with 3-4x better efficiency, thus 3-4x less consumption for the same output.
The simplest way for your issue is to use a DC-DC converter to bring down the voltage to a more appropriate level (8-10 V, roughly) and then power the Peltiers individually with that voltage. You can just connect them parallel to the source, you just need to respect the maximum output current. Or, if you have a fixed 24 V DC source, you can connect three or even four _identical_ Peltier coolers in series. Then each Peltier would experience the same voltage which is the source voltage divided by the number of Peltiers in series. For example, you have three identical Peltiers in series, then each would run at 8 V. But it is very important to use similar Peltiers, because if they have different resistances, then they would run at different voltage and the overall current in the circuit would be different which might not be the best for the devices.
@@CuriousScientist Yes maybe a 24V/48V power supply coupled with a DC solid state relay for perltier's module in series can do the job.... Maybe I should look to water-cooled models since probabalty I can plug my close loop water circruit with it.
Im making peltier aircon..as of now its 60% done..im an hvac tech ill try to apply my knowledge in it..will post the result after testing
I am very curious (really!!), so please keep us posted. So far no one came with their results despite the fact that many people left comments about it. Cheers!
ive actually thought of using peltier as an air conditioner but not for a room just the inside of my shirt... XD
Sony already did that. :) Sony Reon Pocket.
I can understand the cost side of a large project such as an AC or heater, and that it would draw a lot of power. But having one or 2 Peltier models and a few small fans, you can easily make a small desk AC or heater depending on the polarity, and can work well as a small thing to have on your desk for comfort if you can't place a heater or ac unit near you. Or just to make a neat little coaster that can chill and heat drinks.
No, the problem is that one or two Peltier coolers don't have the sufficient power to cool the air down even just for a "local AC". I tried it and showed it in one of my videos. There's essentially no difference in the inlet and outlet air temperature in the case of a single-Peltier air cooler. And even that system was really expensive.
@@CuriousScientist Right, yes that makes sense.
Peltier devices alone are incredibly inefficient, however they can be used rather effectively in an indirect evaporative cooler. Using evaporation to cool down water that's then pumped through a radiator, adding a TEC to the loop would further cool down the water at the cost of double the energy consumption. Is it an AC? No, but it can drop ambient temperature by 30F in a small room. Anything larger than that would be unfeasible as increasing the amount of TEC's in the loop decreases the coefficient of performance well below that of an AC unit.
The temperature drop that you gain with the evaporative cooler becomes a "loss" from Peltier's perspective. You basically increase dT by introducing a cold fluid to the cold side. Higher dT would mean lower Qc. I would rather try to use the evaporative cooler to cool down the hot side of the Peltier cooler and then use only the Peltier to cool something. Since the hot side would (ideally) be under ambient temperature, you would not need to create a very large dT, so you can have a larger Qc. But it is still very energy-demanding.
If i want to make a peltier air conditioner for my pickup i prefer installing a second alternator instead of compressor to supply requirement power if even stock power rate doesn't be enough. So it doesn't need piping, R124 and leaking problems,season maintenance and very cheap and simple to make.
That's also an option. I would be still concerned about the complexity of the controls and the cooling.
Appreciate the video! Working inside the house all year led to the insight that CO2 really builds up. Any insight on how to bring new air into the house (specifically into one room of the house) during all four seasons (especially winter and summer) without wasting the indoor heat (winter) or cool (summer)? A fan doesn't really accomplish that. Also, air exchange systems (HRV/ERV) cost a fortune ($3 K - $5 K) when the idea is to get fresh air into one highly used room rather than the whole house. Thank you.
Hi Rob! Unfortunately, this topic is outside of my expertise. I guess it would be better to ask a HVAC expert or someone in a similar field.
@@CuriousScientist Thank you very much for the response! Much appreciated that you took the time to reply. Your video saved me a bunch of time in my life. Thanks.
I am glad that I could help. I also try to answer every single comments and questions.
It’s called a window unit. That’s what we use down south there is a control on the window unit that allows you to let in fresh air from the outside. Down here you can Buy them for anywhere from $100-$500. Depending on how fancy you want.
Thankyou for posting this. Hopefully the countless people who claim to have built air conditioning units with Peltiers on TH-cam will view this first. You are correct, you need at least 2kw of cooling power to cool the average room.
Thank you! Unfortunately, I am a bit late and there are hundreds of fake Peltier air conditioners on TH-cam, haha. But, hopefully people will watch this and also accept the fact that Peltier coolers are not good for air conditioning. Have a nice day!
@@CuriousScientist I have tried to educate them that 100 watts of cooling power will not cool a room but they don't seem to listen or understand. I'm an aircon engineer by trade.
Then you know even more than me! The point where most of the people get confused and falsely convinced where they see that the surface of the cold side can go below -10°C or even -20°C with a very simple setup. This creates the false impression that these devices can cool well, since the surface is so cold it is even "producing ice". The only thing that they "forget" (they don't know it, I would say), that when only the surface of the Peltier is cooled, there is only a tiny amount of heat is being moved from the cold side to the hot side. This allows a large DT, so even with a 40-50°C hot side (i.e. not so good cooling) one can easily see the above mentioned sub-zero temperatures. Because of this thing that they see the ice, they cannot accept the fact that this has nothing to do with the real cooling performance when considerable amounts of volumes have to be cooled.
@@CuriousScientist yes, it's the air temperature coming off the cold heat exchanger that matters, or "air off" as we call it in the AC trade. To cool effectively you need to see an air off below 10 degs C.
Also, if it was possible, why are there no commercially available residential aircon systems using Peltiers?
And the answer is "Linear Control", "Kalman Beaucy" and optimization. And in this case you can use the Peltier device for measuring Temperatur difference for the control input.
Old video, but i have gathered so far, the cooler the hot side, the lower the temperature you can get, but also the more power it can pump. I am currently working on a device that has 12 volt peltiers running at 8 volts, and watercooling the hot side as good as i can with large watercooling loop.
Your description is not entirely precise. There are 2 parameters that you can trade off: Qc, which is the cooling power (how much heat you can pump from the cold side to the hot side) and DT, which is the temperature difference between the cold side and the hot side. The performance charts also use these 2 parameters. And either you increase DT and you have to sacrifice Qc or the other way around, but you can't have high DT and high Qc simultaneously.
It does not matter if your hot side is 50°C or 20°C cold, if you maintain the same DT (let's say 30°C), Qc will be also the same, therefore the pumped heat will not differ. On the other hand, if you want to pump a lot of heat and you want to reach low temperatures, then you have to keep the hot side as cold as possible. This also comes from the fact that I always tell (and told above) that the lower the DT, the larger the Qc. But you can clearly see this from the performance chart as well.
the delta T isnt as much of a concern unless using as a generator. To drive the unit and use it as heat pump or AC the efficiency of the device is best at 9amperes and below (by your graph) and the limiting factor to cool a room should be around above freezing temperature so lets say at 4degrees C. This keeps the evaporator from icing over. A window AC that creates 2000watts SI (your example) of cooling is not standard by any means frictional losses in the compressor and fan of the unit are pretty high. For me in the US a old standard designed 5-6K BTU window unit uses around 550watts (115v x 4.6A) 5000BTU/hr equates to about 1500watt (SI) equivalent cooling power/hr...That is the part you missed when doing your math (/hr) I think with 12peltier at 12volts and 9 ampere would be a sweet spot since the devices are cheaper than the power transformer to run at high amps. If the use of the TEG unit and the design of the system we are discussing is built for best life and efficiency it has the capability to go above COP1 where the standard AC unit CANNOT! As well the TEG can act more like a invertor driven variable speed scroll compressor heat pump unit it can be set to pace the needs of the space to be cooled with the right control systems in place. I would start with a set of aluminum tanks that sandwich the TEG units between using quality liquid metal thermal interface materials and high temp silicone around the units so the sides cannot transfer temp to one another.. Step 2 insulate the tanks individually very well with 3 or more inches of foam insulation board. Step 3 mount the tanks high on the wall 5-6feet* and plumb the hot tank outside to a large surface area thin design radiator like used in HVAC condensers mounted above the height of the tanks but on the outside wall at a 30-45degree angle this side we will let thermal stratification do the work to cool the condenser applying our hot tank line into the top most section and the bottom to return to the tank. If a fan is needed later we could ad one but since we over size the condenser by so much i doubt a fan is needed. We install a small tank above that hot side condenser to be our fill point so no air is in the system so it can thermosyphon. Step 4 we install a substantially sized automobile radiator below the height of the cold tank, adding high static pressure fan and shroud to get the best results. Step 4 install controls and thermodisk switches for the fan and the tanks to peltiers transformers which shouldnt cost as much as the content creator said. There are transformers that easily do 12v 9amps maybe even wall warts that can do that load for about 10-25 dollars each. Final product is 12x12x9amp 1300 watts plus our fan wattage of 200watts or so. 1500 total watts drawn from the power source and 1300watts directly to cooling with 0 friction or efficiency losses but 10-20percent transformer losses. Brings our consumption up to 1650watts/hr.. Here is where i cannot help without an example but i would like to assume a cop3 is very possible and heating or cooling versions could be built and operated at sub freezing temps like the new style Heat pumps are doing. So we should have ended up with a 15K+ BTU air conditioner (similar to a 240volt ac window unit) but we are below the standard wattage limit of a common US homes 120-15amp standard receptacles safe zone of 1800watts on 14guage wire.. Unless you opted to use 240v AC to DC transformers which would be slightly more efficient and no where near the circuits limits. I 100% think it is possible and you should too. Downside is all the parts which could possibly live beyond the standard 5 years a window ac lasts as well if a breakage occurs your not going to walmart to but a entire new unit you only need the part that broke. The AC to DC transformer and the high static pressure fan might be annoying sound wise but i dont think any more so that a cheap window ac and since you are in charge of the controls you get to play with fan speed, cycle times, and all that jazz. Replacing a like sized 5-6K BTU/hr ac unit would be even less TEG's but i wanted to show a good example of how much more cooling is possible and still be inside of a standard wall receptacles wattage range. For you guys out there that are creating things never let anyone stop you from trying it for yourself!....
Thanks for the detailed comment! I am still waiting for people to build a proven AC system based on Peltier coolers. If they are so good, why are they not available commercially and why are they not replacing the conventional units?
@@CuriousScientist Not available commercially partly due to being solid state device if built correctly it doesn't fit manufacturers agenda of planned obsolescence and to not be user serviceable. There are projects people show that are functional but everyone wants to give flack because it is set up as small experiment and not as a real world device but fact is there in the experiment that it is feasible. I dont disagree there arent enough large scale experiments and that is due to the costs. The costs are above a traditional AC system in the beginning but since it is solid state and only if done properly the fact it can last a long time and be user repaired the upfront cost is recouped over time. Ii think another issue is over driving the units rather than working inside the efficiency scale each unit has. We wouldnt by a car and run it around at 6K rpm all day long but everyone playing with the TEG does that. Just like i pointed out your model of TEG has a sweet spot around 9amps and i personally would start there 12volt 9amps using pc power supplies at first as a test find the BTU output and scale unit to my needs. This way the TEG is never under stress enough or bleeding cold and hot sides together due to being over driven.
@@CuriousScientist th-cam.com/video/ZDLN_tMxSQA/w-d-xo.html this video is good example for both your argument and mine. this unit shows some potential but there are changes that could be done.. He draws air from nearest the reservoir that is hot and pumps the heat into the test space. We do not know if his space was in a time of day that it is under solar thermal gains. He is running a high static pressure fan on the TEG displacement unit (air-handler side) but there is very very little surface area in the cold side exchanger, this is another major flaw. If you think about traditional air handler it has A-frame coils because the standard radiator design doesnt have enough surface area also. To cool a space we do not need sub freezing temps we need right at freezing and a superior exchange rate so we dont have a saturation issue on hot or cold sides. This video was done on a table top right near a window it could have easily been set up to displace the heat out the window. My point is there are faults to designs and many are only playing around with the idea they are not being serious enough to get a good result. Many use the cheap small tubs of thermal pastes this is another fault there are better products out there and NO they are not all created equal. The transformer he is using there for the TEG's is under 30 dollars and is not capable to send 9amps per TEG this is another fault. The one he uses easily get online is for CCT and other hobby uses and has a pot switch to change the output which he does close to the end but he saturates the units. The TEG prebuilt he has he has not a clue if the water blocks have adonized coating under the block touching the TEG and i venture to guess it is adonized on both sides which would reduce the water blocks effectiveness. All together a good video showing how a whole unit is laid out but for function of said unit has many flaws or issues to be addressed before giving a honest result.
@@CuriousScientist Thx for taking time to discuss this with me. I wish i was financially in position to experiment with things myself but i have to live vicariously through others and share my thoughts only.
@@masterdebater8757 No problem, I like to discuss about this topic, I am really interested in Peltier coolers. I am also limited financially, so that's why I don't scale up my experiments. I have plans for that, but I need to save up some money. Until that, I am trying to perform my little tabletop experiments and draw conclusions from them.
What about people using peltier modules to make mini refrigerators - are those realistic (long-lasting) designs?
Yes, I also made one, check my videos. :) Fridge is a relatively small volume and with a good insulation, you can focus the cooling power on the load and not on the compensation of the losses. It will eat more power than a regular compressor-based fridge due to the inefficiency of Peltier coolers, but it can work. Much more feasible than an AC. So much more that you can also find commercial products. I saw mini fridge for boats and cars and I also found a wine cooler. Actually I will make a new video on this topic during the upcoming weeks because I have recently received some new parts for this project. Stay tuned!
*awesome explanation sir, on how to read a performance curve chart, you are amazing!*
Thanks! I am glad to hear that you found my explanation useful.
Only a cold fan could be made out of peltier 😆... you are right. Better to buy an small ac !
Yes, a small AC is more efficient and cheaper. Both when you buy it and when you are operating it.
I'd like to cool the inside of an open cooler and keep microgreens at a certain temperature and humidity. I wonder if this would be a good use of Peltier-based cooling.
Hi! It depends on the volume of the things to be cooled. If it is a small box in your kitchen, you can probably do it. If it is a larger room that you want to cool indirectly, that will be challenging. If you can provide more details, I could try to see if it is feasible. I could at least guesstimate the parameters.
@@CuriousScientist Thanks! I want to cool a medium sized cooler to about 60 degrees Fahrenheit. I'd like to do this in a garage where the temperature will probably get to about 90 degrees in the Summer. I may have an LED grow light above that could possibly generate a significant amount of heat, but if it were a few inches above the cooler, I think most of that heat would get dissipated into the garage instead of the cooler. It would also be great if I could use it to heat the microgreens to 60 degrees in the Winter when temperatures may drop into the 40s. The ideal humidity for growing microgreens is around 50%, which is what the garage is at most of the time.
A standard sized tray is 10 inches by 20 inches. So, any cooler that can accommodate that is ideal.
This seems totally doable. I still need to educate myself on microgreens, but I can see that they are grown in some sort of trays (in fact, my first Google search lead to a 10" x 20" tray). Is this some sort of hydroponic setup where you would like to cool the water to 60°F (15.6°C) or something different? If it is a water bath that you want to cool, that is relatively easy, but the system has to be sized to the task carefully. If you want to cool the surrounding air only, then that will be a bit challenging. Probably some box or tent would be required to provide some kind of insulation. But since we are talking about small volumes, this should be doable.
@@CuriousScientist In some methods, there will be two trays with a little bit of water on the first one. The seeds are in the second tray inserted on top of the first one. However, I think it is better to just cool the air to the height the microgreens will grow since all the water will evaporate. I'm thinking the microgreens will grow 6 to 8 inches (less than a foot). Maybe, there could a separate enclosed container of water (or other liquid or solid) underneath the trays to retain cold temperatures.
Yes thats why most of the youtube videos only use this to just cool a drink or two. Thermoelectric not currently viable for cooling capacity above ~250 Watts .What are your views on Stirling for -80C to -20C cooling ? I think it has potential to replace cascaded vapor compression.
Yes, people try to "misuse" Peltier coolers. It is not impossible, but it is extremely impractical to use them for AC purposes. Regarding the second part of your comment, I honestly have no idea about it. I have never encountered those devices and it would be silly if I would say anything without any knowledge. Sorry!
Thank you for this great video! I was very willing to use peltiers to cool something down but this video really made me realized that they cannot be used to cool down. But unfortunatelly, I had already got 5 peltiers from the past and I do not know what to do with them. I have researched about what to do with peltiers and noticed that the most logical project is making a refrigerator. Or, what else can I do with peltiers? Everyone says that peltiers takes a lot current and spends a lot energy. Then what is the point to manufacture them? I believe that there can be a valid project to use them and that they are not consuming the energy as much as an iron or a toast machine :) Thank in advance and have a great day!
Hi! Peltiers have a huge are of applications. They are often used to cool laser diodes due to the thermal stability that can be achieved with them. They are also used to cool silicon detector of x-ray detectors. And they are also used in other electronics where you want to avoid vibrations for example, since this is a solid state device. For example hobby astrophotographers use Peltiers to cool the ccd of their cameras to decrease the thermal noise.
@@CuriousScientist Thank you for this great explanation! You are the only one who has a lot peltier research on TH-cam as I noticed!
You are welcome!
Make a thermoelectric generator.
It doesn't worth my efforts.
i was allways taught if u have lots of energy to throw at it it would wrk but like he said just not eco for some people some have lots of batteries and entergy to throw at it i made one for a science far to prove a teacher wrong but it was really challenging i was able to get it -40 on cold side with watercooling it used a ton off entergy 😊 but awesome video and cheers to all
Yes, it is not impossible, but economically not feasible. I could also reach below -45°C temperatures without any particular effort. But reaching very low temperature does not mean that you can cool down anything with it. It is exactly the opposite. There is a tradeoff between the minimum lowest temperature on the cold side and the amount of heat that you can move from the cold side to the hot side. The less heat you move, the less cooling you do.
Personally my interest is on power generation from temperature differences. How much power can be produced? At what cost? And what min/max temperature differences are needed? Does the greater the temperature difference increase the electric power made?
Hi! I never tried power generation, but they are extremely bad at it. Probably just a few watts. Also the issue is that they would need a large temperature gradient for better power output, but on the other hand it is difficult to maintain the difference because heat can escape from one side to the other which deteriorates the efficiency.
I have made an experiment out of candles and ice. But you need so much heat. I almost powered my Xbox controller with it. But, 2 LEDs were enough for me. ☺️
@@CuriousScientist For one the minimum is 6 degrees from what I understand but what I wonder is if you double it too 12 degrees does the power output also double or is there a graphed gradient of electric output per degree of difference? As for keeping a seperation, that actually isn't a problem, you put each side in insulated chambers to keep the constant temperature seperation. Chamber side heat is solar charged and chamber side cold is water cooled. It would also be beneficial to maximize surface area with redesigning the flat seperator into a tube shape that could be utilzed as tubes like a radiator.
Too add the inside of the tube and the outside would have a temperature difference that could have continuous flows and thus produce a countinueous electric current.
I have personally never tried to use them for energy generating because they are very inefficient. Electroboom made a video on his attempt if I remember correctly and he also explained that these are not good for this purpose. It is enough to generate a few Watts maybe, but that's all.
Nicely done, professor! Too many novices don't understand the math involved, so they make dumb mistakes, the biggest one being ignoring the heat that comes off of a Peltier device. Just because you can generate ice on a very tiny spot does not mean you can freeze the entire room with it. By applying basic math, you have shown the folly of almost all of these TH-camrs.
Thank you very much for you positive comment! Yes, it is so simple! Unfortunately, a lot of people still don't believe me, and a lot of people fall for the fake aircon videos. They just get blinded by the ice forming on the surface.
put the heating side outside of the room, make a good insulation and in a tiny room you wil notice the difference, obviously it won't work in a big room and in a shitdip project.
@@idontcareaboutyou7757 Yes, the concept is the separation of the two rooms. However, just the separation will not help. Still, a lot of cooling power is needed (which requires a lot of Peltiers), and a very good cooling of the hot side is also needed. Otherwise, you lose all the cooling performance due to the too hot hot side. You still need that 1-2 kW of cooling power to have a noticeable change, even in a small room.
@@CuriousScientist yes, you did the maths very well, something i'm no good about, but it was very clear to me by the first step that if you don't cool the hot side, the performance will drastically drop, and that's why separation and insulation is crucial, plus the volume of the room. If you consider the cost of the energy for the power to cell and heat sinks (at least one each side) it will never be efficient, and that's why at nowdays we have not a peltier based air cooler on the market. But if you consider the right evironment, for example a car, with a almost free energy generator (alternator/battery) and you make a duct wich brings the cool air in the car, leaving the hot part in the bonnet, being it a tiny space i think you can get a reasonably good fresh air intake, probably not a real A/C, but something making a difference.
Silly me. I thought a better way to transfer heat would work...dump that water pipe and tubing and any thing that might actually transfer heat easily
20 devices and hidronic project (water pump) works!
Nice!
what about if you isolate the exterior and the interior? exemple you put it in a window and isolate both sides? will it work?
It's not about whether it will work or not. It is not impossible to build one, but it is not feasible. You will need a plenty of units, a lot of (adjustable) power supply and it will consume a stupid amount of electricity.
It seems like if you could transfer the heat from the hot side away from the room you are trying to cool then it wouldn't offset and cancel out the cooling of the target room and thus dramatically increase the efficiency of this system.
It would be a great system if you had two areas near each other in which you were trying to cool one and simultaneously heat the other. Like say a walk in refrigerator in the winter time when you would need all the other rooms heated besides the refrigerator.
@@willhchrist100 "It seems like", but it does not work like that. Of course, you need to separate the hot and cold parts (like with a split AC or a fridge/freezer), otherwise it won't work. But still, these units simply do not have the efficiency to keep up with the compressor-based ACs. Even though it is not impossible to build one, it is much more expensive than the compressor-based version and not only in the material cost but also in the running cost. Even if you could use the waste heat for something, the cooling part would be still inefficient. Peltiers are not made for these tasks, they have different purposes.
Nicely explained. Peltier technology haven't improved so much since the first devices, let's see in the future, perhaps if someone develop new ideas.
Analysis like this helps a lot to clarify the present situation and maybe motivate someone to break this limits
Thank you! I guess, there should be some breakthrough in solid state physics. The current Peltiers are limited by the characteristics of the materials used in them. Maybe if someone comes up with a new material or something. Let's see if these results become obsolete in a few years.
@@CuriousScientist I haven't watched the video yet so I wouldn't know if you talked about this but they are indeed limited by the materials and there is a new technology called ArcTech and it's a peltier module with new materials that are beneficial compared to the old. Thanks for the vid. Going to watch it now!
Hello, just one curious question. Can we somehow squeeze out some efficiency using clever control system techniques??
Hi! Sure, you can increase their C.O.P (coefficient of performance), but for that, you need to decrease the power you run them at. So you will end up needing more Peltier coolers and more complicated cooling because now you have more modules to cool. They are fundamentally inefficient due to how they're built, so it is very hard to noticeably increase their performance.
Solar panel + electric capacitors + electric coverter 4 medium aluminum radiators each radiator have one cooling fan on it + car radiator liquid + big radiator with big fan to cool all system water + all that will work for 12 thermoelectric peltier each one have heat sink on the hot side with small aluminum radiator to let the water walkthrough it in small box that have a fan inside it to push coold air
To the wanted area
Note : all the radiators should be insulated with exhaust pipe out of the cooled area ☺️
What is the cost of the whole device?
your line across for the 80c change ... will result in approximately 5 watts ... or 5v at 1a ... a valid useful voltage AND current and you should be using a LOGARITHMIC scale for the wattage as it changes exponentially NOT linearly since it is a transistor device it has a base value to overcome BEFORE it will function think a diode curve .... to get it on a straight line it has to be plotted on a log scale ...
These charts are in the manufacturers' datasheets. I guess they have their own reason why they plot it like this. I just read the charts.
I know this is over a year old, but I was wondering if you can revisit this topic, as, I own a cold plate, that can literally freeze a steak, and it's built out of a thermoelectric cooler, and a heat sink. This means, we can get severely cold Temps, and thus, why I thought a small rv ac unit, might be possible from thermoelectric coolers now days. If I'm wrong, please let me know. If they've improved to freeze a steak, one would think that would provide a decent amount of air cooling, no?
A piece of steak is not at all comparable with a room. It is a piece of wet meat in a direct contact with the cooling surface. Also, with Peltiers, being able to make very cold temperatures is not the same as being able to move a lot of heat (i.e. cool down stuff). One of the main principles of a Peltier cooler is based on the trade-off between these exact things. Either you maintain a large temperature gradient between the hot and cold side of the Peltiers or you move large amount of heat between the sides. But not both at the same time.
I think this video confuses efficiency with capability. The displayed peltier cell is clearly capable of transferring around 160W of heat from the cold side to the hot side (less if the cold side is cooler - 100W of heat when the cold side is 20˚C and hot side 50°C). So, it is very clearly capable of functioning as an air conditioner just fine. The problem is that a standard compressor-based air conditioner would use a lot *less* power to transfer the same amount of energy than the peltier cell.
Now, 160W transfer is nowhere near the high end of what peltier cells are capable of. Peltier cells capable of 300W of heat transfer exist (those take around 450W of power to do so - very inefficient compared to compressor-based ACs, but still can do the job).
There also is a way to bring up the efficiency (although very slightly) by minimizing the time the peltier spends consuming power without transferring heat (when the cold side is too cold) which you can do with a few temperature sensors measuring the hot & cold side temperatures and a microcontroller consuming a few microW on it's own.
Compared to a compressor heat pump air conditioner design, a TEC based design will be very space-efficient, which makes it possible to deploy in cases where the former wouldn't be able to fit.
TL;DR: Thermoelectric Cells *can* be the basis of an air conditioner and will do everything a standard residential air conditioner does. The only problem is that they'll be very inefficient while doing so. The efficiency can be slightly improved by regulating the power input of the TEC based on hot&cold side temperatures.
Basically that's what I try to say in the video. It is not efficient, therefore not really feasible to use them as AC. I know that they can move so much heat, but at a cost of efficiency. I never said it is impossible to use them at AC, but it is very inefficient. I even have videos proving it with experiments.
@@CuriousScientist I mean, you say you never said it's impossible, yet the title of the video is says you cannot.
Also, Efficiency != Feasibility. The process of heat transfer using a TEC is inefficient, and in cases where a compressor AC may be used wasteful. That however doesn't make doing so infeasible.
Have you watched the whole video? I was also referring to those fake Peltier cooler-based AC videos which are on TH-cam and telling that when people try to replicate those, they don't succeed. And I know that efficiency is not the same as feasibility, but when you have something with 5-10%, maybe 15% efficiency, is it really feasible?
@@CuriousScientist well, the TEC-based AC videos I saw had the problem of keeping the "hot" side in the same environment as the "cold" side. If you did the same thing with a compressor AC, you'd have the same exact problem.
As for the question of efficiency - keep in mind that ACs in the strict efficiency sense (heat transfered/energy input) are above 100% efficient. The 300W TEC in that sense is about 60-70% efficient.
The main flaw of those videos is not (only) that, but it is the fact that they try to cool with a simple 60 W or 100 W Peltier running at maximum current. Unfortunately, many people gets the false impression of the Peltier coolers because of those videos.
BTW, I also test them with the hot side located at the same room (I have no more space), but I don't test how much they can cool down the room, but I measure the difference between the inlet and outlet air temperature. That also reflects the capabilities to some extent.
Agree. Compressor is less expensive but very noisy.
Yes, where noise is critical, they might consider solid state cooling. But it is often easier and cheaper to just isolate the compressor.
The power VS temperature difference graph you use is not commonly found on most of the Peltier device. Most of them give Power VS Voltage and COP vs Voltage.
A little Google searching will give you the curves. You can find a lot of different datasheet for the same device. Some are more detailed.
Using Pelletier is a bad idea, unless you address reasons for its inefficiency..
Causes being;
1. One of its functionalities is an unwanted outcome. To wit, while using it as a COOLER, you will have to dissipate heat, absorbed at cold side.
2. It always produces Ohmic / Joule heating, which is also a menace (while working as a cooler)
3. There is always thermal bleeding between cold and hot sides.
4. Cooling area is very limited or otherwise Cost per cooling area is high.
The above said 4 reasons make Pelletier horrendously inefficient (as a heat pump)
Personally speaking, working on a project which addresses all the 4 reasons inefficiency. Almost completed it.
Thank you, yes, this is an excellent list of the "drawbacks" of Peltier coolers. Maybe not in this video, but in other videos, I also mentioned these, especially point 2 and 3. Those two things really make it inefficient. But, to add to this list, it is also limited by its working principle. The electrons inside the material who "carry the heat" (not a scientifically exact definition, but it is easy to grasp) are not as efficient as the expanding and condensing gas in a regular, compressor-based cooling system. Your project sounds very interesting!
@@CuriousScientist
Thank you for the compliment, because of motivation, it carried.
Just another point to mention.
Everybody cares about cooling down the hot plate only. On dissipating heat from hot side, you get the required cooling on the cold side. But still then, problem persists, Delta T remains the same, so also is the thermal bleeding between plates.
The project remedies all the 4 crisis.
By the by, there are reasons for inefficiency with Vapour Compression system also.
Could it possibly be used to cool down a 40 gallon plant terrarium? Also, do Peltier devices remove moisture or anything like that?
Edit: My best guess is that the cold side could draw moisture in the air. If that is true, would Peltier coolers be bad for very humid environments?
Depends on how low you want to go with the temperature. I have another video where I built a roughly 15 gallon (~60 liter) well insulated cooling box and I could almost reach 0°C (32 F). If you can use more Peltiers than I did, you can do it, since it is a relatively small and enclosed volume. Make sure to check my playlists on my channel and search for "Peltier cooling box". In the future I will build some more Peltier coolers like that so make sure to subscribe! Cheers!
Replying your edit: Humid environment is bad for _unsealed_ Peltiers. The water will enter the crevices and the constant thermal cycling plus water will damage the device.
If your Peltier (or the heat sink attached to its cold side) is below the dew point, then the surface will collect the moisture from the air (condensation). If the cold side is under freezing point, it will collect the water (condensation) and the water will freeze on the surface. This ice layer will grow thicker and thicker which will diminish the heat transfer, thus the cooling efficiency between the cold side and its environment.
I realize my comment is a bit late for the video but I did want to mention something. Given that there are operating costs (cost of electricity) 9 amperes would make more sense in the long run for the same cooling (more devices at a lower amperage to provide the same Qc). With that being said, at -30 DT you only use 87% of the power running 9 amps instead of 15 at 15 volts.
To make labeling easier
Wc = Watt cooling
Wp = Watt power
29 devices running 15 volts and 9 amps would produce 2030 Wc while drawing 3915 Wp = 51.85% Wc / Wp
20 devices running at 15 volts and 15 amps would produce 2000 Wc while drawing 4500 Wp = 44.44% Wc / Wp
While your initial cost of setting up the system would be greater, assuming fixed electrical costs, over a certain period of time 29x15V9A system would come out on top from a cost perspective.
It is still comically far from traditional compressor style AC units like the one mentioned in this video, 2000 Wc while drawing 800 Wp which is 250% Wc / Wp)
It is great that others also contribute with some calculations and show that it makes no sense to use Peltier coolers for air conditioning. Thanks! Let's hope more people will start believing facts instead of random videos with obnoxious background music.
@@CuriousScientist I will preface this with this is my opinion and only that, if we ever figure out fusion and start getting more than a marginal amount of power in return, I would prefer a Peltier AC unit compared to a traditional compressor for 2 reasons, sound and environmental. Obviously this setup will be horrendously outmatched in terms of efficiency but if the only sound I have to deal with is moving air for a traditional window unit, to me that is a win. The quality of life improvement is worth the extra power and again, this is a personal preference and opinion.
Sure, if we had limitless energy available, we could have many cool stuff. Silent cooling is definitely a nice thing, especially if you are surrounded by multiple of those units. Using just a fan instead of using a compressor would definitely decrease the noise. I guess you probably know, but there are Peltier ACs (I never denied their existence), but they are extremely expensive and as you math also shows consume a lot of energy.
@@CuriousScientist As for the energy, it doesn't have to be limitless, just very abundant to the point where the cost of a MWh is comparable to what a KWh is now. The difference between a compressor AC and a Peltier AC would be pennies given we have the equipment necessary to handle the initial spike of amperage. With that being said, from just a math perspective regardless of materials used as radiators, you will never get more cooling out of a Peltier system than what you put in. Its a little different for heating but still inefficient comparatively. Lastly, using a Peltier as a solid state heat engine is possible but here RTGs do far better. Peltier devices are neat but they don't have any applications where they really shine.
@@camtech1679 I agree with the whole text except the last sentence. They are fantastic for cooling solid-state detectors. 10-20 years ago you had to use liquid nitrogen to cool down the Si-Li X-ray detectors in, for example, scanning electron microscopes. These detectors are used to identify chemical elements using their X-ray emitted due to the electron beam hitting them (EDX or EDS). Nowadays, thanks to both the evolution of semiconductors and the Peltier coolers (which are also semiconductors actually), these X-ray detectors are cooled with Peltier coolers. I also know that they are used to cool down laser diodes and maintain their temperature extremely accurately. They have some pretty nice, but also pretty niche applications.
Seems to be an old video but maybe still worth to comment. The temperature difference (and hence heat pumping ability) of a Peltier is proportional to current while the waste heat is proportional to current squared (actually it's worse, as they heat up they also get more resistive). So yes, 225W waste to get 100W of cooling is not worth the effort, but dropping the current to 9A, the waste heat will fall to maybe 60W for 70W of cooling (COP > 1), and dropping this further to around 6A you could get 50W of cooling for 25W input, COP ~2.
Now, while 50W doesn't seem like much, if we combined 10 devices we could achieve about 500W of cooling at a moderate cost and COP of 2. Again 500W might not seem like much, but remember that the big reason we need super powerful air conditioners is that we let rooms get really hot and then expect to cool them down very quickly. Once the room is cooled, it often only requires a few hundred watts to maintain the temperature. So we could have these kind of devices running constantly at low power/high COP we could have good overall result. Note also that if only 200W of cooling from the Peltier bank, the COP just keeps gets better and better.
The big mistake everyone makes (including in the video) is to push the Peltiers hard. Run them in the 30-50% of spec and they work great.
I keep track of all comments, regardless of the age of the video. No worries!
Aren't you the previous person from 2 days ago? The details are suspiciously similar. :) But maybe I am wrong.
Dropping the driving power sure increases the COP, it is shown in the datasheet. But, it also increases the number of components needed for the same Qc. I guess there is an "optimal" trade-off between COP and complexity. 500 W might be little when we consider that the room might be not very well insulated. You said "once the room is cooled". Yeah, but if you only have 500 W cooling power available, when will that occur? Could work with very efficiently insulated rooms maybe or where the temperature fluctuates a lot, and during the colder night the system can catch up. There are actually legit systems where you can use your house as a thermal battery and you simply play with the heating/cooling of the house. It is very promising, but it is probably not the Peltier cooler technology that will solve it.
My video is not saying that you *should* run the Peltier at max current, rather the opposite, and if you check my other Peltier cooler-related videos, I always advise _against_ running the Peltier coolers at their maximum rated current, and I always explain why (Joule heating (quadratic) overpowers the Peltier cooling (linear)). The video depicts a typical scenario which one can see on TH-cam where people claim that they have built a Peltier AC (typically with 1 single Peltier cooler) and they blast it at max current. So I just simply followed their example.
Cheers!
Thanks! I guess like a lot of people I think Peltiers are cool (pun intended?) but frustrating. But I think the solution is more than just quadratic/linear factor, but also the influence of the heat capacity and heat conduction of the components in the system. If modelled correctly I think we can find a lot more benefits, but it's hard math. One challenge for me was a "Butter cooler" which can keep butter 10°C below room temp with no moving parts. I failed many times using trial and error, and eventually decided to model the system, ran the math and found out that two Peltier devices rated at 85W/8.6A in series (on top of each other) run at just 0.5A (about
Peltiers are definitely cool! (Pun intended, too!)
They are not easy to operate, but once you figure them out, they can be useful, I totally agree. Unfortunately, as you also see in the other comments, you can not convince people with math and numbers despite the fact that they can tell you exactly what's up.
Just because something becomes cold when we run a little current through it, it doesn't mean that it can do anything related to cooling. Some people have a hard time accepting it.
It depends upon what's the heat generated in a peltier? If we take second law of thermodynamics the heat generated cant be more than the cooling generated (primary work done). I can explain it thus if a refrigerator is left in a (small) room with its doors open, it WILL cool the room as the heat generated will be minuscule visavis the cooling generated. I dont know how true its for the peltier. Will the cooling be more??? or is it the heat???
If you leave an open fridge in a room, it would _raise_ the temperature. All the losses from the work being done, which are not transformed into cooling are dissipated as heat. This is why the condenser and the evaporator are isolated in every cooling devices (fridge, freezer, AC..etc). For Peltiers, as they are about 3-4x less efficient, the Joule heat is more emphasized. This is also why the Peltier coolers will show a funny behavior as you increase their current. Above a certain current, typically 60-80% of their max current, the temperature of the Peltier cooler's cold side will increase by further increasing the current because the Joule heating overpowers the Peltier cooling.
Yes. The compressor will behave as a heat pump and raise the room temperature.
but is peltier effective as a fan blowing cold air to me directly?
This video will answer your question: th-cam.com/video/_F6XFvycpRg/w-d-xo.html
But, there is no "if" in efficiency. I mean, it does not depend on the usage, it is still a Peltier cooler, so the system's efficiency will not change.
@@CuriousScientist wow that video was so detailed, thank you so much for the information.
I am glad to help!
Running a 12715 on 6A is much more efficient, then you get a COP of about 2 which might be okay depending on the use case. If someone has a very small room it might be a viable option. But ofcourse you'd have to find the devices for a cheaper price. $5 would be way too much.
And that single unit will produce maybe 30-50 Watts of cooling power. Which is only 40-times less than a typical mobile AC's performance. So, yeah, it is not really feasible in an economic manner.
yes this is correct. other alternative is thermal energy using solar evacuated tube water heater and use refrigerant. its like a hvac
I use a peltier to cool water in a 50L container, then I circulate the water to the crypto mining servers to cool the radiator that I installed at the back of the server.
That way, the cold air flowed by the fans of each server is focused only at the back of each server. For the room I just installed an ordinary air conditioner.
But indeed if you want the air in the server room to be cold, then the correct thing is that the hot air coming out of each server is directly discharged outside the room using ducting. This way, not only the chips on the server will be cooler, but the room is also much cooler.
But there is also a note, the server room should not only use the same cold air for days, because (I don't understand the cause scientifically) in my practical experience, the psu for each server will be easily damaged if the air in the air conditioned room is not circulated regularly with outside air.
The result is that the server room cannot be very cold, because we have to deliberately introduce air from outside with a hotter temperature into the server room that we have cooled using ordinary air conditioning.
How many Peltier coolers are used to cool the water, and which type? At what parameters (U, I) are they running? Crypto miners generate rather large amount of heat, so I am just wondering how you cool them. Why do you need Peltier coolers? Would not be enough to just add a radiator to the water tank?
Would cooling an insulated doghouse be a suitable application for a peltier "AC"? Moving 500 W at a 30 degree F temperature difference?
An insulated dog house would be a feasible project in my opinion. I could cool down an insulated box below 10°C, so a dog house could be also doable. But you would need several Peltier coolers and a good cooling for their hot side.
Peltier elements are commonly used in consumer products. For example, they are used in camping, portable coolers, cooling electronic components, mattress pad sleeping systems and small instruments. some uses definitely won't be suited for large use.
Yes, this is not new at all. However, they are still super inefficient.
@@CuriousScientist I work personally on some form of cooling project related to sleep tech and will implement peltir method for prototyping
Would appreciate someone experienced in the technical aspects before the next canton fair(sourcing side) i’ve reached to specialized companies that manufacture industrial chillers and design specific peltier modules for the different use case. some feedback on the technical side of the tech is need to be honest. If you are interested let me know we can talk about it. 👌🏼
Sure, I can be hired for consulting. My contact details are on my webpage.
@@CuriousScientistsent.
OK. But I already replied an hour ago...
but guess what i mad 1 with 2 120watt paltier modules and it works not good as a freon aircon but it works better then the air coolers
Show me the build and the numbers.
How about using it to cool down a small wooden box for some pet?
That could work! Insulated area and smaller volume. For terrariums, it can work, but the consumption will be a bit high (in my opinion at least).
Hi there, how about if it was used in a car to support the air conditioner? Car air conditioner stays as is just add the pelier (with heat exchanger and all) with the hot side towards the engine bay and cool side in cabin? Or do you have any other ideas? Car sees 55C climate and in idle the ac pretty much does nothing. I've added an extra fan to the condenser as well and still not cooling enough. No gas leak. Just super hot climate.
Hi! I think it would not help. Especially, if you want to put the hot side in the engine bay which can be very hot. The larger the temperature gradient the Peltier has to maintain the lower the cooling power it can provide. If your 3-4 horsepower (2-3 kW!) AC cannot keep up with the hot climate, the Peltiers will be pretty much useless. Creating the same cooling power with Peltiers would be extremely expensive and complex.
@@CuriousScientist what would you do to add more cooling to the cars AC ?
Unfortunately, I am not a car mechanic, so I cannot give you a proper advice. But I guess you need to buy a more powerful AC for the car. Peltiers would not help if the regular AC already struggles.
@@CuriousScientist thanks for the replies and the great videos !
It is my pleasure! Cheers!
What if you use another peltier to absorb the heat produced by it and save some electricity produced by it and put some hit sink on the cool side to maintain its cold side
It won't work. It is extremely inefficient to generate electricity from the heat. You won't save anything and the complexity will be an issue.
Tnx bro i know this video is about a year ago.
Hope u answer that.
I have 5m to 5m Room and i make a plan
To build an ac with peltier
Like 20pic of peltier
And its easy to cool it and also the power and the price its done
I just wannted to know can 20pic of peltier device make my room cool?
❤😍
Hi! 20x Tec12715 or maybe even slightly smaller units would do the job. But you would need a LOT of cooling for their hot side and you would need a lot of electricity, probably a few kWs. I don't think its feasible or economical.
Excelente video , me gusta mucho cuando la gente expone sus criterios sobre una base lógica , y motiva para que se realicen los experimentos en otros lugares , realizando mediciones y bajo condiciones bien precisas , gracias por su video .
¡Hola bienvenido!
Did look into this a little, and for my plan is to build a sleep pod - so much smaller area. Heat venting will be ducting flow into the loft and onto the bathroom extractor vent. That's the plan.
Looked at stacked peltiers, though was looking at large slab of metal between them to buffer things out more (all insulated as well). Oh to have large blocks of copper.
What are your thoughts upon cpu heat-sinks with heat pipes? Considering large solid block with 4 of those in-line with fans in middle all in a nice box that has ducting inlet and outlet that goes right outside via loft.
So for my plans, less than 4 peltiers and really talking size wise a bed sized fridge. Though re-tasking an old PC case and PSU, will be factor, salvaging as much as possible.
Stacking the Peltiers will drastically decrease the cooling power. I have a video on this with supporting calculations and also a demo. Reaching very cold temperatures on the cold side does not mean that you can cool with them. CPU coolers are good to keep a Peltier cooled, but it depends on the type. And I can already tell you that 4 Peltiers probably won't be enough.
Hi, I am trying to build a personal ac for my study room, i am not trying to cool down the whole room but just my study table as i am planning to use the ac at the wall which is near my table, So it is basically like a split ac format, Inside the indoor unit, there will be a copper tube bended like the evaporator( like in an actual ac), the ends of the copper tube is connected to a flexible pipe which is attached to the outdoor unit, there will be 3 cpu fans to push out the air from the indoor unit towards the user( Cool air), there would be a small net between the fan and the copper tube to reduce moisture content, In the outdoor unit, there will be a well isolated container, with 3 peltier module's cold side facing inside it. there is a submersible water pump which is connected to the end of the pipe from copper tube as i mentioned to create a closed loop- water circulating system, 3 peltier modules( tec-12706) is used to cool down and maintain the temp of water, after reaching the desired temp, 2 of the peltiers cuts off and 1 work continuously for an hour to maintain the achieved temp and switches to the second peltier, and the 1st one cuts off, this is repeated in cycle by an arduino for energy efficiency, and ofc there will be 3 radiators which is made to be used with 12706 module, the cold water from the container circulates through the copper tube which will absorb surrounding heat and carry it away back to the container where the water is cooled down again bcoz of the peltier modules. The cooled air is pushed out by the cpu fans towards the user, the outdoor unit is placed at the window. i am using 2l of water for circulation, i don't which know which peltier module will cool down the water rapidly,
I am really confused whether if this setup works to cool down my study area, which peltier module is the best for my project?
whether if i should use a 12v 29a power supply to power all of this. I could really use an expert's insight, I am just a 14 yr old boy and is interested in this stuff, i hope that you would understand and give me some advice :)
If this works, ofc i will give you videos showing it's work, i will probably post it in my dead gaming channel lol
Hi! Check my relevant videos, I show that these systems are not really good for air conditioning. I have a video on a specific Peltier-based air cooler. Maybe that could be something for us. But if you want to save money and avoid headaches, just forget this approach and buy a proper AC.
@@CuriousScientist tnx for the reply
@@CuriousScientist i saw that video and yeah it pretty much explains it but my doubt is if it at least provide some level of cooling to the nearest atmosphere
It can blow slightly cold air at you, but it comes with a lot of noise (fan) and cost. I don't remember the exact cost, but I think I spent like $300 on the hardware (Peltier module, 2x360 mm radiators, pumps, 6 fans, power supply...etc). $300 already buys you a small mobile AC that can cool your whole room...
If you run a cooling block on hot and cool side then the cold side water will cool then run the cool water through a evaporator with a fan pulling through the evaporator
Cold water evaporates slower, it doesn't make any sense that you described. I think, at least.
@@CuriousScientist please read now makes a little more since.
@@ChosenHunter1 I got it for the first time too, but the idea itself does not make any sense for me.
@@CuriousScientist hey I hooked up 5 6amp peltier to 2 blocks and ran water through them. The cold side I set up a loop through a computer radiator and after 20 minutes the radiator dropped to 20 degrees F below my room temperature 🌡. The hot side block was just drawing water from my sink since I didn't have another radiator and the hot block water temperature was 110 degrees F. Not bad if using it to blow directly on you at a desk or a very small room.. 1 or I'd would prefer 2 radiators for the hot side with fans cooling them.
Nice! But how about the radiator (I guess you mean heat sink) temperature if you blow air on them constantly? Of course it cools down if there's no airflow, since there is not too much heat transfer, but it would be interesting to see what happens if you generate some airflow through the radiator.
If its possible to remove heat from hot side to outside of house then it will work as portable air cooler for one person. Is it possible?
I never said it is impossible, but it is not economically feasible. Check my other videos, it would cost a fortune to assemble a system that can provide acceptable cooling performance.
Couldn't an air cooling unit be made by isolating the two sides properly with appropriate insulation, the hot side making use of heatsink and fan feeding out through a duct similar to how a tumble drier does, while the cold side has a water cooling block attached feeding a tank with a low flow rate pump pushing water from the tank to a loop that is coiled in front of a fan similar to traditional air conditioner units which then feeds back through the water block before passing back into the tank?
Not really. Some practical explanation: th-cam.com/video/3dmQDf3GcpY/w-d-xo.html
Don't look for how it won't work; Look at how to make it work better! In a small space loke a car or small office, this works great if you exhaust the hot air outside.
It doesn't.
If the outside temp is 60 degrees Fahrenheit, and the inside of my room is 85 degrees Fahrenheit, I want as many options as possible to cool down my space to a comfortable level. But you might ask, "Why not just put a regular $10 fan in your window, dummy?" To that I answer, have you ever lived in an agriculture/farm based city? Sure, I could put a fan in my window at full blast to cool my room to the pleasant exterior temperature, but my room would smell like decomposing cow diarrhea, burning rubber and vomit as a result.
TEC/Peltier cooling has its place, albeit a somewhat niche product for people who live in cities that smell like rotting garbage. Matching the outside temperature is all many people need... but if the outside air smells obscenely foul (for whatever reason), it would be nice to achieve that temperature without pumping in the outside stench to your home/room. TEC/Peltier cooling can achieve that.
Our consumer markets are becoming far too constricted nowadays, and nobody is broadly innovating anymore. Everything is being designed for a small subset of people as "universal for all", rather than society as a whole which has a lot more specific and unique needs.
You don't need Peltier for that either. It can be done with regular split AC which circulates the air which inside and does not bring any air from the outside. It does 4, maybe even more times efficient than the Peltier. The Peltier system will cost you more than a market-made AC, believe me. If you just want to match the temperature outside, you can just build a simple heat exchanger. The Peltier is used if you want to cool _below_ the ambient temperature. Then, if you add the Peltier cooling to the equation, a huge amount of extra cooling and energy will be needed.
Innovation is there, don't worry. If something is profitable, they make it. This is not profitable at all.
i just purchased 5 12v 6amp units for $6 shipped so prices have gone down in the year since this was made
Yeah, that five 6 A Peltiers will barely produce any cooling power, but at least you will need a lot of cooling for their hot side and a very powerful power supply.
I live in 120sq.ft dorm room with two fans, I was initially going to buy a window AC but Air cooler are cheap, small. Also it's kinda illigal to bring AC. I had an idea of using a Peltier for cooling the water to around 18°C or below 20°C, its normally 29°-38°C outside. And I technical have unlimited power (there is no power metre each room there is only one for whole block). Saddly there is no way to get AC facility here so yeah, I have read most of the comments, its not fecal for most of the people but do think fecal for me?, I think I can cool the water to 18°C or lower with 4 Modules? Or is there a more efficient way to cool water? Which is under 150$
Also pretty cool explanation
Planning to use small DC pump and fans with a heatsink outside the room. Technically the whole model outside the room
Hi! Why would you try to cool down water? How is that related to your room? Sorry, I don't get it. If you have unlimited power, then you can try to assemble some "air cooler", but the budget might be tight. You would need several Peltier coolers (4-8 or even more), heat sinks, pumps, radiators, power supplies...etc. Check my Peltier-related playlist and look for the "Peltier air cooler" video. Then go to my website and check the Parts & Tools page. You'll find all parts there. Maybe within your budget.
@@CuriousScientist the water is for the air cooler, basically a big radiator with a fan
@@anno-user So you want to cool water in a reservoir, then you want to use this cold water and circulate it through a radiator so you can make cold air. You can calculate every detail easily and then you can see the power requirements. So, you'll be able to pick the right type and amount of Peltiers and size the system.
Dear ... What do you think about using a Peltier to cool the water in a radiator, then using a Hall ventilator fan through the radiator?
Hi! No, it won't change anything. Actually, it will decrease the already bad efficiency because you add another step to the heat transfer. It will not give you any meaningful results.
@@CuriousScientist
But the car to be cooled with a radiator, which is hotter than room temperature, and all air coolers that work without Freon operate in this way. The addition is only cooling the water to give more effect.
I don't want to offend you, but based on your comments, you haven't got any clue about the basic physics of cooling. But still, you came here with a question, I answer it, and you still doubt what I say...
First of all, watch my videos more carefully. In one of my videos, I discussed this exact thing. Search for ""Enhanced" water cooler". In cars, you cool spontaneously only. What I mean that the car's engine is well above the ambient temperature when it is running, and the water cooler brings it down somewhat but the whole circle is still above ambient (70-90°C easily). The "freon" cooling that you are referring to is a totally different principle. The "freon" (which is in fact not freon, because it is forbidden to use it due to the fact that freon is harmful for the environment) cooling uses a compressor and forces the material to change its phase. This phase transformation absorbs and releases heat and this is how you cool with "freon". This cooling involves a compressor which compresses the gas to help the process. This cooling is "non-spontaneous", and you can go below ambient temperature. In cars, you just circulate the water with a pump to transfer the heat. There is no phase transformation involved.
Also, your idea is still unclear. How do you cool the hot side of the Peltier?
Furthermore, why would you transfer the heat to the cold side with water? What would happen if the water would freeze? Your system would be screwed. Cooling a heatsink with the cold side of the Peltier is perfectly OK, no need for water. All those videos you see with these solutions are FAKE.
If you still have doubts, build the system, upload a video of the system with properly carried out measurements and let me know. :)
@@CuriousScientist
I really have no idea about about the basic physics of cooling so I ask you
Also, I do not question your answer, but I was hoping that you would open your mind to the questions
I think I came to the wrong place
thanks
@@mohamedsaleh-ni9mq I answered everything properly and even added extra information to all of this. I don't know what else you expect.
Is it possible to use it as aquarium chiller?
It depends. You'll need a large amount of Peltier coolers to keep an aquarium cool.
would be suitable for other applications and not necessarily AC for rooms. there is so many applications that one could consider
Sure. It is used for cooling semiconductors, for example, Si-Li X-ray detectors or laser diodes. It is also used for maintaining voltage references at a very precise temperature.
@@CuriousScientist Ive watched the full video
Peltier is damn interesting 🤣
I know, that's why I produce videos on them. :)
You can get 10 peltiers for 50 bucks, 150W each. But the only problem is removing the heat. One big chunk of alluminium heatsink with 5cm long finns could probably be powerfull enough to be able to removing the heat fast and efficient, also, only with fast spinning fan, minimum 120mm. I do have 3 of those 150W ones and when they are connected all together and everythink works all together , i think they could cool down a 30m2 room quite a bit, yes, it is not a much difference but outcomming air have 10 degrees so.. and now you can imagine what 10 of those will do. They are inefficient that's a fact! but who cares, they are not ment to be used as air conditioning devices, they are way more usefull in car fridges, bewerage coolers etc. But with 10x150W you can cool 100% something, not only your beer but also your house. Paired with solar panels, they could be pretty handy because for the split system AC you need a powerfull inverter and i'm telling you, they are not cheap as you think. Almost every regullar 3 or 5kW inverter shuts down when the compressor in the AC kicks in. You need atleast 6kW one ( only if the AC is 1 phase ) and 9kW when is 3 phase. This minimalize impact on the surge current and inverter won't be able to shut down, for the AC you need a huge power gap sometimes unprofitable, the inverter and AC costs 150 times more than 10 peltiers 150W each. You don't need special electronics. Everything you can now buy via alliexpress and you good to go.
1- 10 peltiers 80 bucks including shipping
2- 2 DC DC regulators 30 bucks ( 1 reg. To each 5 peltiers )
3- temperature sensor with trigger output ( 10-15 bucks )
4- wires ( lets say 20 bucks or none when you find them )
5 - maybe reelay or nothing, you will set it up how you like it
In the end you will end up with 300-400 bucks AC system when you also add radiators for liquid cooling, pump,clamps, water heat removing blocks, fans, heatsinks, thermal compound, tubing.
400 for all, atleast 10k for the split system and powerfull invertor ( not to mention money for workers ( when you can DIY thats plus ) and also cables, mounting equipement etc..
You are just speculating... "I think", "could probably be", "should"...etc. Have you tried to actually build such a system? Have you read the datasheet? There's no way you can buy 150 W Peltier coolers for so cheap. Also, 150 W is definitely not the cooling power, but the electrical power (current * voltage). Even if you find a Peltier that can do, let's say, 150 W, it can do it when the temperature difference between the hot and cold side is nearly zero. Thus, you barely drop temperature. Also, aluminum heatsinks, at least those you described are definitely not sufficient for a 150 W Peltier...
Please redo your math after actually reading the performance charts of the coolers and after actually understanding how they work.
@@CuriousScientist i do understand what they are capable off, the pros and cons etc. I'm electrician engineer so those types of topologies does not make me any frustrated as looking in to the plans for house electroinstallation. This is really simple and you dont need to describe it any further if you know all things behind that peltier. I bought 3 peltiers 150W each, really 12V 12A i measured that and that is almost 150W and yes, they were cheap. I paid roughly 9€ for all those three peltiers including shipping. And yes, they can output a lot of cooling power but in an inefficient way. I'm not a peltier fanboy but they are in some ciurcumstances pretty handy. My gelid tranquillo rev.3 barely cools 1 peltier enough to keep the cold side in -20 degrees range. 150W is divided in to two sections, 1- cooling power and 2- heat producing power. When you connect this peltier to the 12V PSU and you are able to cool the hot side perfectly, the cold side can be -30c . Whole cooling power of the peltier is maybe 40W max, so 110W is produced as heat you need to dissapate somewhere quick and efficiently. If you have 10 of those 150W, the cooling power could be somewhere between 400-500W and heat 1000-1100W
Reaching -30°C does not tell anything. You have a bare, exposed cold side without any thermal load. Of course it will go down to very low temperatures. But that also means that the temperature difference between the cold side and the hot side is maximized, therefore, the heat that can be pumped is minimized, essentially zero (just a few watts). Put another CPU cooler on the cold side to, run the fan and see what your cold side temperature becomes. It will probably won't even reach 10°C. I did these tests already, check the "debunking Peltier air conditioner" video.
And that 400-500 W cooling power is about 1/4th-1/5th of the cooling power that you need to cool down a 20m^2 room... It simply does not make any sense to use Peltiers for air conditioning as compared to an AC because they are so inefficient and they need a relatively "complex" construction to operate. You can just buy a "portable AC" and you just need to plug it in and that's all. It is cheaper both to buy it and operate it.
I want to cooling for room (10*12*12) size. What is the setup to need for this?
A proper split AC.
You can justify based on: the components are cheap or salvaged free, you can power it with the solar panels, you don't need refrigerant and since the refrigerant gas is now banned to be sold to the general public you don't need to pay for gas recharge made by a certified person .
My counter argument is the following:
First of all the solar panels are expensive. I just quickly Googled them in my country, maybe not the cheapest prices I found, but if I want to buy let's say 1000 W of solar panels, it would cost me 800-1000 USD... at least... You would then need voltage regulators and power management system to feed the correct power to the Peltiers. You cannot just wire the Peltiers and the solar panels directly together. Also, you cannot leave the solar panels unloaded (open circuit condition), so you will always need to match the load with the produced power. Furthermore, where do you put the solar panels and all the electronics? For example, I live in a block of flat and I have no way of placing several square meters of solar panels anywhere. Nowadays ACs run with special refrigerants, they are not banned, not at least here where I live. I can buy them easily in specialized webshops.
Do the math and you will see that for price/watts (cooling power), regular AC is much cheaper.
Hello I am just bored on my lunch break with a question. I have a black car with no AC and it gets super hot in the summer. I thought I could make one of these and stick it in the glove box, which is directly below the vent where my car intakes interior air. I do not expect it to blow ice cold like normal AC, not even close, but would it help a little?
Hi! I don't think it could keep up with the summer heat. To build something using Peltiers that would provide something meaningful would be quite costly. Probably a normal car AC would be cheaper.
Really apreciate your knowledge.
Buy ac and get solar panels. And forget all the hastle😅
Hi! Yes, it is easier and cheaper. 😉
since Peltier plates run on DC power, one may be able to build this using earthen batteries for bad situations. i imagine that freon would be almost impossible to make, without an understanding in chemistry.
Freon (or the other gases that replace freon) are related to an entirely different cooling process. Solid state (Peltier) vs. phase transformation (gas-to-liquid) use different principles. But unfortunately I have no idea what is an "earthen battery" and how it is relevant for this topic.
@@CuriousScientist earthen batteries are simple batteries that use soil as a medium. assuming an electrolyte is added, power can be acquired this way.
i brought this up, because of the fact that the Peltier is a simple to understand system, which can be applied in deep survival situations, where it would be impossible to create chemical refrigerants, and it runs on DC power, so battery banks could run it, instead of AC power, regardless of whether it is for AC or for food cooling.
Now I get it, thanks! Well, yeah, you can run them from batteries, but since they are not the most efficient things on the World, they would need a lot of power. If you can provide enough power to them via batteries, it is OK to use them that way but I don't know anything about the capabilities of the earthen batteries.
@@CuriousScientist i used them in this comment, because they are simple. if someone has produced potash from a fire pit, then one could use this to increase alkalinity, which i image would make for a good electrolyte when everything is damp.
Such a nice explanation..
Thanks, I am glad that you liked it.
my idea to use small car evaporator and water block with peltier when the water gets cold it cools down the car evaporator and we add a fan to the car evaporator so it pumps cool air
Check my most recent video and you will see why it is challenging.
@@CuriousScientist ok
@@CuriousScientist can i ask you a question please
Of course.
@@CuriousScientist What's the best way to cool water water block or the Aluminium tank
But could you use it in a ocean cooling setup, where air flows over the cooling side with heatsink fins to ensure max air cooling, and the heat side has heatsinks that have constant cold ocean water flowing over. The only issue is the electricity right?
I do not know what is ocean cooling setup. The issue is that the initial investment (buying everything) and the running cost (electricity) is much more expensive than buying and operating a proper, compressor based AC. It is possible to build an air cooler (see my recent video: th-cam.com/video/ZDLN_tMxSQA/w-d-xo.html ). But it is stupid expensive and needs multiple parts, so you will end up having a complex but inefficient system.
@@CuriousScientist but if power is not an issue.. i was thinking of using a bunch of peltier as a dummy load to dump all my excess solar production instead of using a heater.. since I could not sell power to the grid... so I could at least use a bit of cooling especialy during hot summer days a lot of exess power... the power applied to the peltier could be adjusted at realtime depending on the amount of excess production.. peltiers esilly diy'd and no moving parts...
@@genome692002 Yeah, if you have infinite power, the situation is a little bit better. However, don't forget that you still need to ensure proper cooling for the Peltier coolers and ideally, you would also want to regulate the power to them and not only just dump the power on them. It is not only the cost of the electricity but the cost of the parts which make this unfeasible. I made a "model system" and presented it in one of my videos ("Debunking Peltier ACs") and even a small system cost me more than $300... So if you want to scale it up, prepare to pay a lot only for the parts.
so the maximum cooling capacity one peltier can offer is just 175 watts?
Yeah, when the temperature difference between the two sides is nearly zero. Not the most useful case of configuration.
I should have seen your video first.
I wasted money in peltier cooler module , it doesn't cool much.its only good for refrigeration.
What was your original intention? Maybe I can help to at least use those things as best as possible.
@@CuriousScientist i was working on peltier module Ac .2peltiers cool one aluminium water block (which is in between) and 2 water blocks to cool hot side . (2peltiers and 3 water blocks)
(water block hotside--peltier--water block cool side--peltier--water block hot side) in sequence.
I used 240mm PC radiator one for hot side and one for cold side . peltier used -12715.
For power i used 450watt computer smps , and one issue is when i connect both peltiers to 12v , wires get heat up.
The 12715 consumes 15 A at max current. Since the voltage is limited to 12 V due to the PSU, the amperage will be around 12 A, I assume. 24 A (2 Peltiers) is a LOT, of course it heats up the wires. If you power and adjust the Peltiers properly, you will get around 200-250 W of cooling power. That won't be enough for an AC. Also, why would you transfer the heat with water to the cold side? The cold side should be _as close as possible_ to the object that you want to cool. So in this case, you should put a huge heatsink with a fan on it.
He curious. What about using Nicola Tesla's "cold electricity" to move hot to cold and vice versa. Possible? Would certain unique coil designs provide efficient air conditioning, theoretically?
I cannot imagine a coil providing cooling power. So, my assumption is no, it won't work as an AC.
18:07 because air is not good at picking up temperatures from solid state object especially when on high flow.
How can this be mitigated?
I have few ideas but wondering if it will truly solve the issue.
Convection isn’t enough indeed
And if you do force convection you run into noise problems
There is no such thing as "picking up temperature". It is called heat transfer. Even if we use your phrasing, air is not "picking up temperature", but it is "shedding off temperature", since it is warmer than the cooler inside an AC.
@@CuriousScientist I am no engineer and the terms are meant to deliver the idea.
“Picking” is used do describe the event where the room air will be forced inside a box that is cooled in order to be quickly cooled before getting exhausted into targeted area.
I hope that clarified my meaning
I understood already what you wrote, I just clarified the terms. :)
If you look at Peltier chips like speakers that you can run efficiently you’ll be OK,,,
If you wanted 1000 W speaker. It would sound better if you had 10 speakers pushing 100 W each and it would be more efficient on heat.
The speakers at 100Watt you could play 24 hours versus one speaker at one ohm playing 1000 Watt would be extremely extremely hot. You could maybe play two songs then you would have to let the voice coils rest/cool down . Simple
Ten Speakers is more inches of sound = 100 inches. 10 inches reproducing 1000 w is less speaker surface area reproducing sound.
Same with the 😊peltier chips,
You wouldn’t want to try to produce 400 W of cooling on four peltier chips( I mean it’s OK).
But like the RMS level of a speaker, peltier I would think have an RMS level also/ efficiency level also, just like the 10 speaker I explained above, more speaker surface area produces more = better sound I would think more peltier surface area at lower power would produce more better cold 🤷🏽.
They’re basically telling you the range and count at which you play your speaker /Peltier chip depends on efficiency /heat and longevity ie sound performance /cold performance since its a peltier not a speaker . ✌🏽
Can we built a Ac using fridge part's like we only change the evaporator and condenser
It is the Peltier coolers which are too inefficient for this purpose. I don't recommend using them.
@@CuriousScientist no not peltier,the conpresser from the fridge
Ahh, yes, that would work better.
there is air conditioning with peltier cells, what are you saying there?
They are very special applications. I'm not saying it is impossible, I am saying it is not economically viable. You need a lot of parts and it will consume a lot of energy. Check their price and energy consumption. The example I am focusing on here is mainly those fake Peltier ACs, which are promoted by several uneducated video creators on TH-cam.
If it is soooo inefficient, why are still being used then??...and why do you have links to buy them on your description? I wouldn´t send people to buy something that doesn´t work.
I plan to build a water cooler using Peltier modules: this cold water will circulate on a spiral coil to cool the air from a fan, and into a small confined, thermally insulated space like 7 or 8 cubic meters. It´s not obviously an entire room, and I plan to use solar panels and a 20 Ah battery for this, during the hottest hours of the day in my country there is plenty of sun to run this and more.
Using the thermal mass of the water volume and a styrofoam cooler will allow me to get a consistent decrease in the temperature, hopefully. The main issue, I think, is running the Peltier module intermittently. This way you avoid the severe contraction/expansion effect, and the circulating water in the meanwhile will be cooled by the cold side, until a limit is achieved.
Regarding the excess heat, it will be properly dissipated TO THE OUTSIDE, and not to the very same space that those TH-camrs you mention are trying to cool down!!!
A DT of 30 Celsius is A LOT for practical effects. I don´t know why you choose such a high delta.
The video is too long, also, I think.
It´s all about WHAT THE COOLING NEEDS ARE, and how you achieve it. I have the strong feeling that conventional cooling equipment based on gas expansion is going to be outdated in the near future.
Oh and by the way, the initial testing will be with a couple of modules recycled from old cooling equipment :)
I will upload it to my channel in the coming next few weeks.
If people still want to buy Peltier coolers for other experiments, or if they just don't believe me and want to build an AC using Peltier coolers, they can find a quick way to buy them. It is a win-win, and no one is forced to use my links. In fact, there are very small number of people who buy stuff using my links anyway. :) And Peltier coolers have their own specific application field, but that field is not air conditioning. They are for example used to cool silicon drift detectors in analytical instruments or CCD/CMOS detectors in cameras. They don't dissipate too much heat, but they need to be operated at really low temperatures, so Peltier cooling is perfect for this application.
Depending on how much water you want to cool, how fast, and how cold, it can work. There are Peltier-based water chillers for fish tanks. It is obviously not the most efficient way, but if you have solar power already available, it might make things cheaper.
You should know that the thermal mass works "both way": It will also take a lot of energy to cool the water. I would run the Peltier continuously, but with continuously regulated current. The closer you get to the target temperature, the lower the power you feed to the cooler.
30°C DT is not a lot. You need a proper cooling to maintain a room temperature hot side, in fact, for a room temperature hot side, you need really cold water cooling... The real hot side temperature which actually determines the final numbers in the equations is not the temperature you measure in the heatsink attached to the hot side. Don't forget that there are electrical junctions _UNDER_ the ceramic plate that covers the hot side of the Peltier cooler. The real hot side temperature should be measured there. So, this 30°C assumes that your hot side is about 50°C and and the cold side is 20°C. I did several measurements where I used other parameters to express the real hot side temperature and I usually got an extra 20-30°C as compared to the temperature of the water in the cooling block.
If the video is long, skip it, simple. I provide the information that I think I find interesting to share. It is not mandatory to watch each second of it.
Conventional gas based cooling will be with us for many-many years. Mark my words.
Looking forward to seeing your experiments.
What are real industrial use cases for these modules?
They are used for cooling silicon drift detectors which are used for detecting X-ray. They are also used for cooling CCDs to decrease the thermal noise. Astrophotographers sometimes mod their DSLR camera and add Peltier cooling to cool the CCD and increase the image quality. They are also used to cool laser diodes. So, it is mainly used to cool some sort of semiconductor part where there is not too much dissipated heat, but you need very low temperatures. I use one of those X-ray detectors that I mentioned during my daily job and I know that the detector inside it is at -52°C.
@Curious Scientist im very bad at math, so how many peltiers is needed to match a 0.5hp AC? Lets say tec1-12706 is what im going to use, how many of that is needed to work like a 0.5hp AC?
It is enough to ask it once, I read all the comments, and react to all of them. See my answer below...
@@CuriousScientist Using Luigi's accent and hand gesture "well where is it? i can not find Jeff's question, mama mia".
I can't find that comment either, but I am reading the comments from my phone right now, so it is more difficult. If I am not wrong, the 0.5 HP is for the electrical performance (consumption). Let's say, for the sake of simplicity: 400 W. Usually, the cooling power is about twice as much in a compressor-based AC. A TEC12706 in some arbitrary conditions can provide 30-40 W of cooling power. So, ~20 pieces would be sufficient. But this is a very "hand-waving" calculation.
I don't think anyone is really looking to cool a whole house. I am just looking to use it the cool down the water in my aquaponics water, and lately a 5 X 5' X 5' greenhouse on solar with it. would that be possible?
This video is mainly a response for those fake videos where they claim to build an AC using one single Peltier cooler with some dodgy cooling. Also it is a detailed explanation of the inefficiency of Peltier coolers and why it is not good to use them in AC applications. For the water, you can try to estimate the power you need by calculating the heat needed to cool down a certain volume of water by a certain degrees. Use the Q = c * m * dT formula to see how much heat you need to pump out from your system. Then you can compare this heat/power with the cooling power of the Peltier cooler(s) you want to use. I have some videos on cooling/freezing water with a different types of Peltier coolers. That can give you an idea about the numbers. Also I explain all the calculations and everything in those videos.
@@CuriousScientist Thank you :)
i see some errors here.
1. your power consumption is 225w and you pump 100w of heat. your hot side produces 325w, not 225w.
2. you may have disregarded the effect of delta on voltage. you seem to have assumed 15a needs 15v no matter the delta.
3. 30 degrees of delta could be distributed to multiple modules by stacking them. this would increase the module cost but along with efficiency thus reduce the other costs.
5. you disregarded the effect of voltage on efficiency. looking at the datasheet, i can see that if i run it at 2v COP is 4 for 10c delta. with this COP i can even stack two identical modules to achieve 20c delta, which i think is good enough. Qc comes down to 15w though, considering the COP that is less than 20w to dissipate. we will be able cut down on other equipment but still pay more. The twist is this seems more efficient than compressor based cooling. Idk in a couple of decades i will be even :))
6. dude you can't just say 20cm x 16cm is large and then call an ac unit small. not cool.
all aside i like peltier because it's low maintenance with no moving parts or high pressure components, special fluids etc.
Hi!
1. You are correct, I mistakenly forgot to add that extra term. But that just makes everything even worse if you add it, because then more heat has to be removed.
2. That's why it is called assumption.
3. Yes, you can stack them, but as you also said, that would increase the initial cost. Instead of buying let's say ten units, you have to buy 20. 20 TEC12715 would cost you about 200-220 EUR... And this is just the cost of the Peltier coolers, nothing else.
4. You skipped 4.
5. I did not disregard it, but did not consider it. Mainly because of point 3. 15 W will not have any noticeable cooling effect. You need about 50x more to make it comparable with a small AC. Now do the math, it is expensive again from the beginning.
6. 20 cm x 16 cm just the surface area of the Peltiers. Then you need all the auxiliary stuff such as coolers, wiring, power supply...etc.
@@CuriousScientist 3. i was also totally wrong about stacking. it's not more efficient. the pumped heat has to be pumped by the next one too. so one unit of pumped heat causes two modules' cost.
5. i did the math and boy it costs like three times as much :))
6. i didn't realize this was you. i know your videos you know your stuff. i would doubt myself a bit more if i realized.
Yea its not worth it on cost of electricity alone even if you get all peltiers, power supplys, heatsinks for free in 2years you will spend more on electricty than new ac+costs
Yes! But you have to be very lucky to receive all that expensive stuff for free. :) In my comparison, as we could see it, the Peltier device cost more already in the beginning and the difference between the money spent will just increase if you start using them in the same way, as the Peltier-based cooler would consume roughly 3x more power...
As I said, it is not impossible to build it, but it is impractical and expensive.
@@CuriousScientist lucky me then, got a ton of tdk lambda ps supplys (300-1500w) water cooling plates and pumps and fans from work. but yea its probably not worth it anyway.
You can try, but I am still saying that it does not worth the effort. I always try to emphasize that it is not impossible, but it is not practical. It will be extremely expensive to run it over a long period of time. If you start from zero parts, compressor-based AC is much cheaper to buy it and also to run it.
@@CuriousScientist yea i know. How ever i am so tempted to do another project. Have a summer place near the sea, would be fun to see if you could just circulate a close loop or open with sea water and just circulate it.
What if you use it to cool a small fin radiator(directly attaching it to the radiator instead of a heatsink).. then flow water through that radiator and use a fan to blow the cool air?
Check this video: th-cam.com/video/ORMKZ2M7hKg/w-d-xo.html
@@CuriousScientist you explain everything very well, and I subscribed, but what if you hooked up the peltier directly to the radiator.. you skip a lot of those steps.. you explained there are a lot of unnecessary stuff!.. tey to cool the radiator with the peltier while water is running through it.
@@B18bVtec And where exactly would you place it on the radiator? There are not flat surfaces on the radiator to mount the Peltiers. Also, radiators are for liquids. If you want to mount the Peltiers on something, there are heatsinks for that.
@@CuriousScientist it would be mounted closest to the inlet of the hot water... So basically this is the configuration.. a tank with water pumps the water to the radiator.. the inlet of the radiator is being cooled so that the water can get cold before returning to the pump.. then a fan is attached to the radiator to blow the cold air.. similar hot water heaters under the sink.. water comes into a radiator(or a coiled water system) which then gets heated.. and exits hot water.
I think you have the wrong idea about how these instruments work. Check my videos. Check the video that I linked in the first response!
Don't understand the charts but my system cost less than £50 and runs off a 200w solar and does great
You should make us some videos, you would be very popular!
You are a real person. These NPCs defending an inneficient tech that doesn't have any prsctical use inside earth are just annoying.
We must seek efficiency.
Pay a little bit more upfront now, or pay the consecuences the rest ofnyour life.
I would not say that Peltier coolers have no practical use at all, but they are definitely useless as an AC. However, I will keep fighting those NPCs. 😄
Do you think is it possible to use 4 peltier 6A to cool a 1m^3 of a "greenhouse" box I am doing ?
It depends on how fast and how cold you want to go. I have a project where I built a little fridge using Peltier coolers, check it, and use it as a reference.
@@CuriousScientist It has to go from 32ºC to 20 (extreme case) don´t need to be fast, I am going to assembly the project this week, if you wanna see I can show you.
By the way I was reading an artile where someone used a PID controller to control the peltier and god better results in speed of cooling, it would be a good video for you channel I think, if you wanna see : Thermal investigation of a thermoelectric cooler based on Arduino and PID control approach
Thanks! I have made my own Peltier controller already some years ago, but thanks. You can look it up on my channel.
You could do one in a car or similar small space
Prove it. A car with its basically non-existent insulation is a tough thing.
Video makes no sense
You don't make sense, either.
Sir may i ask why 12709 can't turn into ice
Peltier coolers are made of ceramic materials and semiconductors. They can't turn into ice. :) But to be serious, since I don't know anything about your system, I can only guess. You are not giving enough power to the unit or not cooling the hot side well enough.
@@CuriousScientist but some vlogger here in TH-cam i saw that thier PILTIER turn into ice . My power supply is 15A and the PILTIER MODULE that ive used is 12709 which is only 9A
I am a scientist and not a vlogger. If you use a 15 A power source without any control and if your PSU can provide around 15-18 V, you will run the 9 A unit at the maximum specifications. Therefore the Joule heating will overpower the Peltier effect and you won't have a good cooling effect. Your experience also suggests that you don't cool the hot side properly. So, put a large heat sink with a fan on the hot side and run the Peltier only at 5-6 A. And watch my videos because I explain how these things work and how they should be used.
@@CuriousScientist im using 12v dc sir so you mean can i adjust it in 14v?
NO! You need much lower voltage.