You are the best and I mean it. Keeping things simple and to the point. Before I can think of next question, you have already though of it and start explaining. Keep it up Thanks
Ok. This is like my 6th viewing. I am studying for NAPCEP and you cover about 1/3 of the test in very practical terms. Your experience shows. I recommended it to my classmates. We all use your website and you are a great teacher.
I find your videos very informative, we are currently using a small 12 volt system with a pwm controller (for the last 11 years), I'm adding 2 more separate systems and have been "discussing" with my hubby the benefits of using a MPPT controller vs buying a cheaper PWM controller, we were gifted two 320 watt solar panels (originally grid tied), this video finally convinced hubby that the MPPT controller will work better for us with our 12 volt batteries. Didn't realize you were also a marriage counselor, LOL 😜
I watch all your videos in the hope your knowledge will rub off. I'm a complete newbie. Usually you lose me after the first few minutes, but I must be learning because I got almost half way before you lost me. lol Keep them coming. I am learning. :)
What a smart and beautiful woman. Looks like Massachusetts Irish. She is so talented at her presentation it makes you want to buy solar panels from her !
Thank you that was a great video. I made my own system 3Kwatt 24 volt battery 5 years ago and all your data and advise was accurate and very helpful. One thing you should mention is that with a grid tied system with no Batteries you do not have any power if the grid dies. People think, oh I have solar panel so if the goes out I'll be fine, WRONG if the grid goes out it disconnects you from the inverter for safety for the utility workers repairing the grid. Also the grid power "Guides" your inverter to the correct voltage and frequency john Randall in California
We have done several videos that talk about the fact that grid-tied solar goes out when the grid goes done, as well as how to add battery backup to an existing grid tied solar system. Here's one example. th-cam.com/video/6WRLdZQeK9c/w-d-xo.html
I like the real world numbers on your channel,most "green" energy people do their magic with numbers to make their product look better.This is the reality users get.
Well that was a good explaination...I have been trying to learn a lot of things about solar panels from various sources and this indeed was very useful.Thanx a lot for sharing this piece of information.
A 60 cell PV panel can actually charge more efficiently a 24V nominal battery than a 72 cell PV panel. A 60 cell PV panel will have a max power point voltage output of 27 to 32V based mostly on temperature. Even in extreme condition when panel is very hot and max power point voltage is say 27V the panel will still be able to charge a battery that is at 28V or even 28.8V at slightly reduced current and max power point power but since panel is that hot it means that you have excess energy anyway so slight reduce max power point charging in those extreme conditions is irrelevant. If cost of 72 cell panels and 60 cell panels will have been the same per watt you can buy 6x 60 cell panels instead of just 5x 72 cell panels for same amount of money and the 6x 60cell panels will sure put out more more energy in all weather conditions. So not only 60 cell panels work with 24V nominal battery but they work better than the 72 cell panels. Also using 60 cell panels on 24V battery can be done with non MPPT controller since you already use the panels at max power point and in that way you save even more money. (60 cell panels will probably not work at all with most MPPT charge controllers and 24V battery since there is no space for optimization). So unless your panels will be very far from the battery and you need to deal with large voltage drops on the PV cables 60 cells are a much better option. I of course use 60 cell PV panels with 24V battery for many years and they perform excellent in both hot and cold weather. Using MPPT in offgrid type applications is useless and if you want to know way search for may video named "Is the MPPT obsolete in offgrid solar?"
ElectroDacus builds a nice PWM controller for charging LFP batteries for up to 3KW of solar. However several problems arise with his comments above regarding costs, using PWM v. MPPT and Panel types. Electrodacus's comments are valid ONLY for smaller solar systems, those built and wired very close to panels, charge controllers and the batteries. Not everyone will do that. When you get above 3KW of solar his numbers don't work. For example, having MPPT controllers connected via high voltage (low cost) wiring and solar array strings many metres apart yields significant DC cable cost reductions which are not available when using PWM charge controllers in the same situation. ie many metres far away in a field. 1) Efficiency is not only about matching the output voltage of 60 cell panels to meet the limitations imposed by using PWM controllers. An MPPT charge controller allows the use of either 60 or 72 cell panels and when there is not much sun about you need every watt of power you get into your batteries. 2) Loading down a solar panel and operating it outside the manufacturers recommended maximum power point profile (whether 60 cell or 72 cell or otherwise) is just plin dumb. You are paying for capability in the panel you can never use because a PWM charge controller is too "dumb" to manage the panel properly. You don't see PWM controllers used in professionally designed systems (3KW and above) for very good technical reasons. That said, I would love to see Electrodacus design and build an MPPT version of his LFP PWM controllers. The only reason he said he did not I believe was the electronics would then have become more expensive and it would have taken him longer to design and build. With modern Off Grid solar systems (going north of 3KW of installed solar panels) just for an average house, using several high voltage panel strings coupled with an efficent DC wiring design, multiple MPPT controllers and new LFP batteries... That is the way professionals do it. PWM controllers are not used by professionals for good reasons.
So,both are right; that is what i thought; i have a 1 kw setup (at full sun...) at 24 volts (60 cells each panel) and the batteries charge well, via cheap PWMs, harnessing the panels` full Amps .
Thanks for clarifying/demystifying terms like MPPT and how the considerations of grid-tied vs. standalone systems impact the overall system design. Now I realize why many solar vendors lost interest when I insisted that I was only looking for a standalone backup system! I wish all success to your business.
With modern Boost/Buck converters, any battery arrangement can be charged by any panel, although closer voltages will give greater efficiency. So, I charge a 48v LiFePO4 pack to 58 volts from 5 300w panels in parallel with a VOC of 44v each. On cloudy days they run at about 36-38v and 43v on sunny days. Excess power is shunted to a water heater through a DC relay switched from the thermostat.
Hi,using say a mppt battery controller is only good to show current going into the battery. The voltage will keep going towards 15volts on a 12 volt battery.This is because the word controller is for the current being drawn by a load,not for what is going in.The only product to purchase is a solar battery charger.The series string of panels does give you higher voltage but average current. Parallel string panels give same voltage but higher current.This is important when the environment around a house roof has many trees which cause shading, which kills each cells output.Thanks
I'm sizing a mobile off grid system for a van and plan to use 2x 60 cell panels in series via an MPPT charge controller, charging two 12v deep cycle batteries wired in parallel. If I understood you this should work perfectly?
Yes. Just make sure the charge controller can handle at least 80Voc input and remember the amps the charge controlelr is rated for is the output, not the input. So if you have two 250W panels, 2x250W = 500W / 12V battery = 41A output. So the charge controller has to handle at least 40A.
I have been off-grid for about three years. Minor upgrades have taken place over that period of time but still using the 16 year old panel from my original experimental system when I lived in the city. I am looking for a serious upgrade, but still intend on sticking with the 12V battery voltage, because everything I have runs on 12V and it is too costly to replace it all with higher voltage things. With that said, I do have a 30 Amp MPPT controller, as well as the original PWM controller that is actually part of the back-up charging system now. The question now id whether I should add one or two more panels, series or parallel, to the existing 125 Watt panel... After watching some of the videos, it looks like I'll be buying a couple of panels, wiring them in series and feeding the MPPT unit while adding the existing panel to the backup system. Then there is the issue of the wind turbines... They produce a much higher voltage than the solar panels and that is a whole different animal in matching them up.
Your expanded system would need multiple controllers managing the system. The 125W panel should stay on its own controller, and the new larger panels should have their own MPPT charge controller. If shading is not an issue, then they should be wired in series for higher voltage and lower current, thus lower voltage drop. Then the MPPT controller will drop the voltage to the correct charging voltage for the 12V battery bank. When sizing the controller, take the total watts it is controlling divided by 12V for the amps output needed. For example, if you add two 300W panels, you need 600W / 12V = at least a 50A charge controller. With the wind controller, if it is charging at a higher voltage, you may need to put in a diode to prevent backfeeding to a lower voltage charger.
@@AltEStore That is pretty much what I thought. I don't plan on more than 300 Watts. The batteries are golf cart batteries, (Trojan t-105). Currently, the 125 Watt panel charges them up fine in the summer but when the shorter days of winter set in, I have to run supplemental charging (generator tied in that I use for cooking). Four 100 Watt 12 Volt panels would be ideal, wired for 24 Volts, 400 Watts is still close enough for my purposes, (14 Amps) I'll never see that here in reality, feeding the 30 Amp MPPT controller. The 125 Watt panel can go back on the PWM controller in parallel with the auxiliary charger. (on the inputs) I am still looking for something that can handle the voltages of the wind turbines, which get higher than 130V in high winds. I knock it down right now with a 500 Watt halogen lamp in series to limit the current but in lighter winds, it absorbs most of the power that could also go into the batteries.
Great video. Took your advice on multiple parallel strings (batteries). I have three strings of four 6v Trojan L16 batteries (12 batteries total). I bought two Blue Seas Systems 250A busbars....going to wire them direct and keep the parallel cables in there too. Sound correct? That way it should balance everything out.
Amy have you done a tutorial on the pro's and cons of series vs parallel solar panel configurations? To me it is best to maximize solar panel voltage, so it will exceed battery bank voltage even on cloudy days, and charge the batteries...So the solar panels will have useful output for more hours per day. I'm sure there are disadvantages, just don't know how to quantify them
A 60 cell panel will charge a 24v battery bank just fine using a pwm controller. Under load or when the batteries are low the voltage drops and the panels hit their maximum power point. You'll only get 5-6 amps on an 8 amp panel at 28.8V, but that's when the battery is almost full. Under load or when the batteries are discharged, 60 cell panels hit there power point at 26V and 7.5-8 amps. I'm not just guessing about this as I have been running a 60 cell panel with 24v battery for 2 years. Sure the panel amperage drops as you approach full charge, but so does the batteries ability to absorb power as it approaches full charge. You do get a little less in the summer heat but you can get 2 x 60 cell and pwm controller (14 amps) for the price of a 1 x 72 cell panel and an mppt controller (10 amps).
So now we know what happened that really smart girl in electrical engineering class that always sat front row center, and that went out of way to downplay her beauty.
Hay Amy thanks again for being so brilliant and giving us a clearer idea. In the picture towards the end of the video where you showed us the 60 & 72 cell panels I also noticed a much bigger one in the background. How many cells were those?
being a newbie on the solar panel, i chose the mono. could i connect the mono with poly panel in the future? i will stay with all mono just to be consistent to the voltage output. i have purchased a 100W and a 200 Watt solar panel, should i connect 100 W to the 200 W downstream? what would happen if i connect the 200 W to 100 W downstream? would it cause the wire heating up? thanks for your video, learned a lot but still many questions in the future. i will use the solar for my mini camper. any suggestion on setting up the two panels on top the camper or keep them on the ground level for better sun exposer?
I purchased 400 watt Trina panels sometime ago and just realized that they had TS4 connectors. Are these interchangeable with the more popular MC 4 connector? I have to purchase branch connectors and want to buy the right product
Goodness gracious me, would I like to go on a date with you. :/ This is the fifth wonderfully informative video I have seen of yours. Thank you and love from Australia.
Hi altE store I have watch so many videos of you and get so much knowledge about solar power system. In February 2020 i am installing solar system in my home in Pakistan faisalabad. I have bought A class solar panels and inverter with net metering which will be use without batteries right now. Later on i will use batteries. Now the point is i am worried about the solar panels connection to inverter because in my locality there is no expert electrician. So can you help me out in connections.
Wonder why it worked for me as far as 24 V charging. I had one 170 watt 37 volt anel with a cheap eBay controller and it charge my 24 volt battery bank all Last summer.
Hi, I am planning on getting a 36 cell panel to charge my battery of 12V, but I am connecting 4 of such batteries in parallel to get enough current for driving a 250W motor, so can I use three of such 36 cell panels connected in parallel to get the out put (12 V 24A) that I need? And will the PWM controller supports this? Thanks for the video its was help full and cleared lot of my questions, I would be glad if you help me out with this, looking forward for your reply :)
Great, the 36 cell panel is a 12V panel, designed to charge 12V battery banks. If you need more than one panel, then wire them in parallel to increase the amps. To determine if your PWM charge controller is big enough for the panels. Look at the Short Circuit Current (Isc) of the panels you are using, and multiply it by the number of panels, times 1.25 for safety. So if your panels have an Isc of 8A, and you are using 3 panels, that is 8A x 3 x 1.25 = 30A charge controller needed.
Thank you, very informative. I wanted to ask, with the new solar transparency cells, are they the same voltage s as solar panels? Definitely appreciate feedback please Thank you in advance. From Australia Cheers.
Sorry, we haven't seen the specs for the transparent cells, so don't really know. It's important to remember that a lot of the cool new technologies you read about are either still in development, or so inefficient it doesn't make financial sense yet. But work goes on, they'll get there.
Hi, thanks for the great information, you said at 4:50 that it is not possible to charge a 24v battery with only one 60 cells panel, if the Voc is about 38V and Vmp is about 31V (so still over the needed 28.8V to charge battery) , what is the problem then?
While you technically can charge a 24V battery with a 20V panel, it is not a good option. When it gets hot, the voltage of the solar panel drops, so in the summer or any hot weather, you may not have a high enough voltage to completely charge the battery. That can cause the battery to be in a partial state of charge for months, which is not healthy for most lead acid batteries. Keep in mind a 12V panel has 36 cells, and a Voc of around 22V. So a panel to charge a battery voltage twice as high should have twice the cells and twice the voltage, thus the 24V 72 cell panels. You can see a demo of it here, th-cam.com/video/4hU6FUiFI2I/w-d-xo.html
I'm curious (don't know if you or someone else can answer) if I have a 100 ah battery and a 60 watt solar panel that puts out approx 5 amps would it be able to eventually put 100 ah back into the battery?
I'm just learning about this recently in preparation to add to an existing 90W panel I have on my 12v RV system. Where does the difference between monocrystalline vs polycrystalline factor in? I live in California but I intend on driving everywhere so from what I understand, mono panels are more tolerant of shaded sun than poly type panels. I have a very limited space to add more panels to the existing run. I'm wondering if I added two or if possible three panels for a total of 390w, would an mppt controller be of any use(I plan on replacing it due to the increased input)? I also will add 4 more deep cycle batteries(or some type of sealed battery, replacing the lead acids if I change the battery type) to my existing 2 for a total of 6. I will be using a computer on an inverter as well. Any suggestions?
+Maxid1 One of our most popular videos is on the differencees between mono and poly. th-cam.com/video/TCq0K3DlFdc/w-d-xo.html However, for such a small system as yours, I would not concern myself with it. The difference is going to be so small, just get whatever panel you can get that fits, don't worry abut mono vs poly. An MPPT charge controller will likely be able to generate more power for you, but make sure you use panels that are very similar to each other. An MPPT charge controller works best when the panels are similar. If you are planning on replacing your battery bank, I suggest getting higher amp hour batteries to minimize the number of parallel strings. It is much better to wire batteries in series than parallel, due to uneven charging and discharging of parallel strings. For example, it is better to wire two 6V batteries in series than two 12V batteries in parallel. Also be careful about adding too many batteries and not enough solar to fully charge them. If you don't have enough solar, you may end up with the batteries in a partial state of charge, shortening their life. I wouldn't go much bigger than a 400Ah battery bank with 390W of solar, unless you are going for days without using it, and you have multiple days to fill the batteries back up.
I have been watching all your videos to gain more knowledge about solar panel. I have a simple question. Let's suppose I would like to buy 30W solar panel, does it matter what solar cell series it is? since 30w solar panel is smaller power than all are available out there.
When the panel is tilted off square with the sun, its AREA is LESS; projected area,that is; if you tilt it off 90º, having the sun hit on its edge, the area becomes ZERO,of course.
I'm not sure I understand your question. Will a microinverter work at night? No, it needs the sun. Newer microinverters can be used with a battery system allowing you to use the energy made at night. www.altestore.com/store/deep-cycle-batteries/lithium-batteries/enphase-energy-ensemble-energy-storage-system-p41457/#ENPENCHARGE10
over where I live the house apparently works with 125 volt... I guess that this would mean that I would need 5 panels of 24 volts... yet.. I wonder... because the house uses the common AC current, and not DC... so the current would need to be made AC... would I need those 5 panels or less??... how many batteries would be needed??... finally should I skip the batteries and connect straight to the main, (grid tie)??
You are correct that you need an inverter to convert the DC from the panels to AC for your house. Whether you need batteries or just connect straight to the grid is up to you, and what your goals are. If you are looking to simply save money and use less dirty electricity, then a straight grid tie is best, if net metering is available from your electric company. Different inverters have different requirements for how many panels they require going into them. You can see how mush solar is needed to offset a percentage of your existing electric bill with our grid tie calculator, www.altestore.com/store/calculators/on_grid_calculator/ If you are looking for backup power due to power outages from the grid, then you can have a hybrid grid tie battery backup system. Create a loads list of what you want to backup to determine how much power you need to store. www.altestore.com/store/calculators/load_calculator/ then go to the off grid calculator to determine how many panels and batteries you need. www.altestore.com/store/calculators/off_grid_calculator/?dwhrs=0
When I first heard about salt batteries, it was stated that they had to be kept at 700 degrees, which eliminated home use. In layman's terms, how are you doing this at ambient temperature.
A few questions: 1. Can three 60 cell panels be wired in series (60v total) going to a MPPT controller going to a 24v battery bank? 2. If so, then what would be the upper limit of panel voltage going to the MPPT? 3. Can one MPPT accept parallel panel inputs of different voltages, e.g., one string coming in at 60v and another at 40v? Thanks.
Answers 1 and 2 depend on the charge controller. Most MPPT charge controllers have a Voc plus temperature compensation of 150V. Those can take three 60 cell panels in series, even in the coldest environments, you'd be under 150V (38Voc x 3 x 1.25 temperature compensation = 142V). If you want to wire three 72 cell panels in series, you'd need a charge controller that can handle at least 165V, like the Midnite Classic 200 or the Magnum PT100. #3 I am working on releasing a series of demos showing exactly that, they should be out over the next 2 weeks. Short answer, if wiring different voltages, but same amps, wire in series (if using MPPT that can handle the voltage). If same voltage and different amps, wire in parallel. If both volts and amps are different, it may not be worth the effort.
lol....no i mean,it will work,but...not well at all.. 3 panels of 60 cells give you 28x3 volts, or 82 volts !!! Danger!!! Danger!! 82 volts *DC* is NO kidding matter !!!! SPARKS will fly!!! Any MPPT will ONLY reduce panel VOLTS It CANNOT raise the amps of the panel, so, no point in using it here ( i mean, yes,but only a negative point..) So, do not feed 82 volts to the MPPT,if it will only output 28 volts to the 24 V batteries,like you said Instead,wire them panels in PARALLEL( around 22 Amps,MAX!!) and you can use a cheap PWM charge controller; That is exactly the setup i have,works well.
Nice and useful videos sir I have a question If I gonna design a solar street light with 27 hours backup if the Load is 65watt and the Sun hours are 7h Then: 1:what battery size do I need 2:what penal size 3:what inverter size 4:if I use two penal(2*150) do I need solar combiner . . . .
To figure that out, we need to know how many hours the light will be on. Let's guess 10 hours, and do the math. I also suggest you get a DC light so you do not need an inverter. Solar: 65W x 10 hours = 650Wh a day. 650Wh / 7 sun hours (are you sure about that number, very few places have that much?)/.65 system losses = 143 watts of solar needed minimum. Let's round up to 150W. Batteries: 650Wh x 1.125 days (27 hours) / 30% depth of discharge) / 12V = 203Ah 12V battery. 200Ah is close enough. If you do use two panels in parallel, you can use a pair of couplers to combine them. See this video th-cam.com/video/9xsf_l_mCEk/w-d-xo.html
Hello Amy, I have my inverter online but I made a small test to see what would be better two strings of 8 or 9 in series. While I was doing this I noticed that 2 of the panels have the VOC 42 while the rest only 40 or bellow. I bought them used at a good price. The Voc on the panel should be 44,4 V. They where set flat on the ground so i was not expecting more but I was expecting to have the same value. Is this normal? Out of 9 180W panels I only got 900 W(panels flat on the ground.). I hope I did not do a bad purchase on the panels.
+Adrian Cheudan That can be normal. Some installers will sort their panels as they come off the truck to make sure that they are closely matched per string. But don't worry too much about it. When calculating the expected output from a solar system, mismatched panels are factored in, so don't worry that 2 of them are 5% lower voltage, they should be fine. I suggest you also test the amps out of each with an amp meter and compare with rated Isc, but that should be don't with them facing the sun and at mid day on a sunny day. That will give you a good idea if the panels have a problem.
I am in the middle of purchasing a decommissioned missile base,,,, I have plenty of room for the solar panels and a big room for batteries . I want to convert the base to run off solar and wind power . Does ur company also do installation of equipment ?
You will lose over half the power from the panel. You need an MPPT charge controller to convert the voltage down to the right level while increasing the amps so you don't lose power. With a PWM charge controller, the volts will drop, but the amps won't go up. You can see us try a 24V panel with a PWM vs MPPT. Same thing will happen with a 20V. th-cam.com/video/V2b7z2eTb5o/w-d-xo.html
It depends on the brand. For example, the QCELL Duo panels do have the high wind resistance. www.altestore.com/store/solar-panels/q-cells-solar-panels-p41041/#HAN370QPEAK370M
Hello. I have a quick question. I’m getting a 6.2 KWh 19 panels LG Neon 2 panels. Paying about 16.5k with federal tax credit. Oakland Ca area. Is that about right? Or is it on the high side.
I'm doing a small RV system... using cheap lithium 36v battery packs in parallel. does the cell count matter if using an mppt controller? The mppt controller I found seems to indicate it's possible to charge input 12v-90v and output 12v-72v... but 36v batteries in a solar system are uncommon so I'm still not sure
60 cell panels are nominal 20V, so 2 in series is good for up to 40V. The Midnite Solar Kid can charge 36V pattery packs. But my question is, what will you use the 36V for? Do you have 36V loads, or a 36V inverter?
altE I do not have 36v loads. I'd have to use a specific sine wave inverter to get to 110ac and another buck converter to get to 12v for lights and some other devices. I got a good deal on some 36v battery packs made of 18650 cells since the hoverboard fad died. that's the only reason for going with a 36v system. I could also take the cells and build a 12v system but I was trying to see if I can save some work.
Looks like you have a plan. There are some 36V inverters out there, just make sure they have one that does what you need for a reasonable price, and doesn't cost so much you end up paying more for the good deal. We run into that a lot, which is why I asked.
I have one 295 watt solar world 36v panel, could I use this with an mttp to charge a 12v or 24v bank? it was free and would like to make a little charge station for phones, laptop, etc.
Absolutely. That's a "20V nominal" 60 cell panel with 36Voc. You can use an MPPT charge controller to charge a 12V battery bank. If you are in a location where it gets hot, it will not do a good job charging a 24V battery bank, unless you got 2 in series. See more on charging a battery with a 60 cell panel at th-cam.com/video/4hU6FUiFI2I/w-d-xo.html
I think there is an error in your calculations. You say that a 72 volt panel can only use 11 panels in a system because 44X11X1.21 is max per NEC. But a 72 cell panel produces .5v x 72 x 1.2 or 44 volts AFTER compensation and 44V x 12 panels is still under 600VDC.
Excellent point. Because of the high voltage of 96 cell panels, they are usually used with either microinverters like Enphase IQ7X or DC optimizers like the SolarEdge P400. Using them with string inverters can have tricky string sizing, so is not often done.
hi ammy.. i am having two 350w 24v solar panels and single 200ah Battery and mppt solar charge controller 40amp.. should I connect pannels in series or parralel to charge my battery and run some load on solar simultaneously?
series increases voltage and watts parralel increases amps... you only have two panels..in series it will charge your battery but if you gonna draw a lot from the battery you need to get the amps up remember you have a 40 amp mppt ..dont exceed it..but you didnt say how much wattage your mppt is dont exceed the wattage of the mppt. so 4 panels of that size is about max for 24volt system you can add 2 more if you want but dont exceed the wattage of mppt.. 40 amp MPPT has a limit of 500 watts at 12 volt 1000 watts @ 24 volt 2000 watts @ 48 volt
So to keep the heat down on your panels, don't Mount them on the roof of you're home. Besides you don't want to be walking on your roof, that protects your whole house stay off of it.
I'm just starting out... There's just too much to learn... Too many variables.... So I watched about 100 videos on starter systems...mainly 12 volt arrays. I bought a 12v 100ah AGM battery and a 100w panel with a 2000/4000 Pure Sine wave Inverter and a HQST MPPT 20a charge controller ... Seemed like a good start but been watchin more and more videos and getting flustered hahaha now wondering if I have enough controller for expansion..
Subbed for sure for a while now. I find myself watching this particular video several times now. I am simply trying to take out of this what I need and in the meantime understanding the full picture - history. Mainly, I am concerned about powering an off grid class C vehicle. I am pretty sure I want around 600 watts, 72 volts, to charge four 12 volt deep cycle batteries wired in series - parallel = 24 volts able to power a small deep freezer and minor additional needs. So in summary, with 41 square feet to work with, can I just drive down?
Terrific. Keep in mind you also have the option of wiring two 36 cell, 12V panel in series to make the 24V. Sometimes that works out better space-wise, if you need to work around a skylight or AC unit. Also shipping a 72 cell panel can be expensive, as it has to go by truck. Another thing to think about is not overpowering the batteries. Most batteries like being charged at about a C-10 rate (plus or minus a couple), which means, for example, if you have four 12V 125Ah batteries wired in series/parallel, you would have 24V 250Ah. You should aim to charge it at about 25A. 25A x 24V = 600W of solar.
Come on by! We are here Monday through Friday, 9AM to 5:30PM. We don't have a storefront, but have some of our technical sales reps and lots of inventory here in Boxborough, MA. I suggest calling first just to make sure we've got what you are looking for in stock, and have someone ready for you. 877-878-4060.
We currently have a bunch of Made in USA SolarWorld 325W 24V panels in stock. www.altestore.com/store/solar-panels/solarworld-325-watt-solar-panel-sunmodule-sw325-mono-v40-frame-p11919/
You are the best and I mean it. Keeping things simple and to the point. Before I can think of next question, you have already though of it and start explaining. Keep it up Thanks
If I ever become President, you're going to be a major advisor! David
Ok. This is like my 6th viewing. I am studying for NAPCEP and you cover about 1/3 of the test in very practical terms. Your experience shows. I recommended it to my classmates. We all use your website and you are a great teacher.
Thank you again. I now plan on watching all your videos, and getting much more *great* information about ALL things solar. Like and subscribed. ***
I find your videos very informative, we are currently using a small 12 volt system with a pwm controller (for the last 11 years), I'm adding 2 more separate systems and have been "discussing" with my hubby the benefits of using a MPPT controller vs buying a cheaper PWM controller, we were gifted two 320 watt solar panels (originally grid tied), this video finally convinced hubby that the MPPT controller will work better for us with our 12 volt batteries. Didn't realize you were also a marriage counselor, LOL 😜
Hubby.......................
@@CarlosAlberto-ii1li yes, and an awesome one too! ❤️
I watch all your videos in the hope your knowledge will rub off. I'm a complete newbie. Usually you lose me after the first few minutes, but I must be learning because I got almost half way before you lost me. lol Keep them coming. I am learning. :)
Thanks so much. Let us know if you have any questions you want us to address. I'm always looking for ideas for videos and blogs.
Angela Fiebelkorn welcome dear Angela good knowlege
I will have to go over this a few times, but i like she gives a pretty good general overview of requirements and outputs intelligently without hype.
What a smart and beautiful woman. Looks like Massachusetts Irish. She is so talented at her presentation it makes you want to buy solar panels from her !
Thank you. And you are half right, Irish/Canadian French.
Thank you that was a great video. I made my own system 3Kwatt 24 volt battery 5 years ago and all your data and advise was accurate and very helpful.
One thing you should mention is that with a grid tied system with no Batteries you do not have any power if the grid dies. People think, oh I have solar panel so if the goes out I'll be fine, WRONG if the grid goes out it disconnects you from the inverter for safety for the utility workers repairing the grid. Also the grid power "Guides" your inverter to the correct voltage and frequency
john Randall in California
We have done several videos that talk about the fact that grid-tied solar goes out when the grid goes done, as well as how to add battery backup to an existing grid tied solar system. Here's one example. th-cam.com/video/6WRLdZQeK9c/w-d-xo.html
I like the real world numbers on your channel,most "green" energy people do their magic with numbers to make their product look better.This is the reality users get.
Excellent basic language to explain. Perfect! Thank you!
Well that was a good explaination...I have been trying to learn a lot of things about solar panels from various sources and this indeed was very useful.Thanx a lot for sharing this piece of information.
A 60 cell PV panel can actually charge more efficiently a 24V nominal battery than a 72 cell PV panel.
A 60 cell PV panel will have a max power point voltage output of 27 to 32V based mostly on temperature.
Even in extreme condition when panel is very hot and max power point voltage is say 27V the panel will still be able to charge a battery that is at 28V or even 28.8V at slightly reduced current and max power point power but since panel is that hot it means that you have excess energy anyway so slight reduce max power point charging in those extreme conditions is irrelevant.
If cost of 72 cell panels and 60 cell panels will have been the same per watt you can buy 6x 60 cell panels instead of just 5x 72 cell panels for same amount of money and the 6x 60cell panels will sure put out more more energy in all weather conditions.
So not only 60 cell panels work with 24V nominal battery but they work better than the 72 cell panels.
Also using 60 cell panels on 24V battery can be done with non MPPT controller since you already use the panels at max power point and in that way you save even more money. (60 cell panels will probably not work at all with most MPPT charge controllers and 24V battery since there is no space for optimization).
So unless your panels will be very far from the battery and you need to deal with large voltage drops on the PV cables 60 cells are a much better option.
I of course use 60 cell PV panels with 24V battery for many years and they perform excellent in both hot and cold weather.
Using MPPT in offgrid type applications is useless and if you want to know way search for may video named "Is the MPPT obsolete in offgrid solar?"
ElectroDacus builds a nice PWM controller for charging LFP batteries for up to 3KW of solar.
However several problems arise with his comments above regarding costs, using PWM v. MPPT and Panel types.
Electrodacus's comments are valid ONLY for smaller solar systems, those built and wired very close to panels, charge controllers and the batteries. Not everyone will do that. When you get above 3KW of solar his numbers don't work. For example, having MPPT controllers connected via high voltage (low cost) wiring and solar array strings many metres apart yields significant DC cable cost reductions which are not available when using PWM charge controllers in the same situation. ie many metres far away in a field.
1) Efficiency is not only about matching the output voltage of 60 cell panels to meet the limitations imposed by using PWM controllers. An MPPT charge controller allows the use of either 60 or 72 cell panels and when there is not much sun about you need every watt of power you get into your batteries.
2) Loading down a solar panel and operating it outside the manufacturers recommended maximum power point profile (whether 60 cell or 72 cell or otherwise) is just plin dumb. You are paying for capability in the panel you can never use because a PWM charge controller is too "dumb" to manage the panel properly. You don't see PWM controllers used in professionally designed systems (3KW and above) for very good technical reasons.
That said, I would love to see Electrodacus design and build an MPPT version of his LFP PWM controllers.
The only reason he said he did not I believe was the electronics would then have become more expensive and it would have taken him longer to design and build.
With modern Off Grid solar systems (going north of 3KW of installed solar panels) just for an average house, using several high voltage panel strings coupled with an efficent DC wiring design, multiple MPPT controllers and new LFP batteries... That is the way professionals do it. PWM controllers are not used by professionals for good reasons.
So,both are right; that is what i thought; i have a 1 kw setup (at full sun...) at 24 volts (60 cells each panel) and the batteries charge well, via cheap PWMs, harnessing the panels` full Amps .
Nice job explaining this process for a change. Thank you
Thank you a bunch for putting out these valuable precious infos,God bless you ,
I love the ALT E videos. They are very informative. I have a lot of 72 cell panels. Still waiting to use some of them.
You can see why there is very few dislikes, there is no crappy annoying music and she clearly knows her stuff.
greetings from Scotland. Lov the vids. Very informative and clear.
Agreed
Great video. I've been playing with solar for a while and you finally cleared up MPPT for me :-)
You make sense to a point lol. It's always helpful! I get more and more rewatching these things after I watch your other videos haha
Wow.. thanks to this lady.. I know now what should I get next... great job.. thank you..
brigth and beautiful explanation...now i know how tosize my project solar system...god bless mam..thanks a lot...
Thanks for clarifying/demystifying terms like MPPT and how the considerations of grid-tied vs. standalone systems impact the overall system design. Now I realize why many solar vendors lost interest when I insisted that I was only looking for a standalone backup system! I wish all success to your business.
Great explanation and presentation. Thanks Amy
Excellent description of the different types of panels
With modern Boost/Buck converters, any battery arrangement can be charged by any panel, although closer voltages will give greater efficiency. So, I charge a 48v LiFePO4 pack to 58 volts from 5 300w panels in parallel with a VOC of 44v each. On cloudy days they run at about 36-38v and 43v on sunny days. Excess power is shunted to a water heater through a DC relay switched from the thermostat.
This is an excellent technical explanation. Good work.
Hi,using say a mppt battery controller is only good to show current going into the battery.
The voltage will keep going towards 15volts on a 12 volt battery.This is because the word
controller is for the current being drawn by a load,not for what is going in.The only product to
purchase is a solar battery charger.The series string of panels does give you higher voltage
but average current. Parallel string panels give same voltage but higher current.This is
important when the environment around a house roof has many trees which cause
shading, which kills each cells output.Thanks
I'm sizing a mobile off grid system for a van and plan to use 2x 60 cell panels in series via an MPPT charge controller, charging two 12v deep cycle batteries wired in parallel. If I understood you this should work perfectly?
Yes. Just make sure the charge controller can handle at least 80Voc input and remember the amps the charge controlelr is rated for is the output, not the input. So if you have two 250W panels, 2x250W = 500W / 12V battery = 41A output. So the charge controller has to handle at least 40A.
altE Thank you, didn't know it related to output amps, very helpful. Have subbed 👍🏼
Great video for Solar 101. Btw I love your big hair!
Can be connected 320 watt 12 volt 3 pannel & 375 watt 24 volt 2 pannel in series
You just blew my mind! So well explained!
I have been off-grid for about three years. Minor upgrades have taken place over that period of time but still using the 16 year old panel from my original experimental system when I lived in the city.
I am looking for a serious upgrade, but still intend on sticking with the 12V battery voltage, because everything I have runs on 12V and it is too costly to replace it all with higher voltage things. With that said, I do have a 30 Amp MPPT controller, as well as the original PWM controller that is actually part of the back-up charging system now.
The question now id whether I should add one or two more panels, series or parallel, to the existing 125 Watt panel...
After watching some of the videos, it looks like I'll be buying a couple of panels, wiring them in series and feeding the MPPT unit while adding the existing panel to the backup system.
Then there is the issue of the wind turbines... They produce a much higher voltage than the solar panels and that is a whole different animal in matching them up.
Your expanded system would need multiple controllers managing the system. The 125W panel should stay on its own controller, and the new larger panels should have their own MPPT charge controller. If shading is not an issue, then they should be wired in series for higher voltage and lower current, thus lower voltage drop. Then the MPPT controller will drop the voltage to the correct charging voltage for the 12V battery bank. When sizing the controller, take the total watts it is controlling divided by 12V for the amps output needed. For example, if you add two 300W panels, you need 600W / 12V = at least a 50A charge controller. With the wind controller, if it is charging at a higher voltage, you may need to put in a diode to prevent backfeeding to a lower voltage charger.
@@AltEStore That is pretty much what I thought. I don't plan on more than 300 Watts. The batteries are golf cart batteries, (Trojan t-105). Currently, the 125 Watt panel charges them up fine in the summer but when the shorter days of winter set in, I have to run supplemental charging (generator tied in that I use for cooking).
Four 100 Watt 12 Volt panels would be ideal, wired for 24 Volts, 400 Watts is still close enough for my purposes, (14 Amps) I'll never see that here in reality, feeding the 30 Amp MPPT controller. The 125 Watt panel can go back on the PWM controller in parallel with the auxiliary charger. (on the inputs)
I am still looking for something that can handle the voltages of the wind turbines, which get higher than 130V in high winds. I knock it down right now with a 500 Watt halogen lamp in series to limit the current but in lighter winds, it absorbs most of the power that could also go into the batteries.
Thank you Solar Queen!!!
How about the 70 volt solar panels...mppt should be able to have a field day with that!?
MPPT will manage that beautifully.
Exactly the information I needed! Thank you
RIP SOLAR QUEEN
Great video. Took your advice on multiple parallel strings (batteries). I have three strings of four 6v Trojan L16 batteries (12 batteries total). I bought two Blue Seas Systems 250A busbars....going to wire them direct and keep the parallel cables in there too. Sound correct? That way it should balance everything out.
+Chris DIYer Anything you can do to keep the connections to the battery strings the same, thus provide even charging and discharging, is a good thing.
Thanks.
Amy have you done a tutorial on the pro's and cons of series vs parallel solar panel configurations?
To me it is best to maximize solar panel voltage, so it will exceed battery bank voltage even on cloudy days, and charge the batteries...So the solar panels will have useful output for more hours per day.
I'm sure there are disadvantages, just don't know how to quantify them
th-cam.com/video/P3YtBrymJdA/w-d-xo.html
Norrbob thank you. That video is for mismatched solar panels. I want to optimize output for matched solar panels
A 60 cell panel will charge a 24v battery bank just fine using a pwm controller. Under load or when the batteries are low the voltage drops and the panels hit their maximum power point. You'll only get 5-6 amps on an 8 amp panel at 28.8V, but that's when the battery is almost full. Under load or when the batteries are discharged, 60 cell panels hit there power point at 26V and 7.5-8 amps. I'm not just guessing about this as I have been running a 60 cell panel with 24v battery for 2 years. Sure the panel amperage drops as you approach full charge, but so does the batteries ability to absorb power as it approaches full charge. You do get a little less in the summer heat but you can get 2 x 60 cell and pwm controller (14 amps) for the price of a 1 x 72 cell panel and an mppt controller (10 amps).
Exactly, that is the setup i have,works well.
Great video with lots of useful information
So now we know what happened that really smart girl in electrical engineering class that always sat front row center, and that went out of way to downplay her beauty.
ohh god..... THis Woman have Amazing Hair. Wish my mom has this thick hair( and I also had it on my head)
yep...the hair's hot
Such a great job explaining! :)
Hay Amy thanks again for being so brilliant and giving us a clearer idea. In the picture towards the end of the video where you showed us the 60 & 72 cell panels I also noticed a much bigger one in the background. How many cells were those?
Thank you so much for these.... its been very helpful
being a newbie on the solar panel, i chose the mono. could i connect the mono with poly panel in the future? i will stay with all mono just to be consistent to the voltage output. i have purchased a 100W and a 200 Watt solar panel, should i connect 100 W to the 200 W downstream? what would happen if i connect the 200 W to 100 W downstream? would it cause the wire heating up? thanks for your video, learned a lot but still many questions in the future. i will use the solar for my mini camper. any suggestion on setting up the two panels on top the camper or keep them on the ground level for better sun exposer?
I purchased 400 watt Trina panels sometime ago and just realized that they had TS4 connectors. Are these interchangeable with the more popular MC 4 connector? I have to purchase branch connectors and want to buy the right product
very well organized information. thank you
Goodness gracious me, would I like to go on a date with you. :/ This is the fifth wonderfully informative video I have seen of yours. Thank you and love from Australia.
Awesome.....simply awesome
There is a good diy green energy guide on EzBatteryKit ( . ) com that can help you save huge on batteries
Rich Machten i see your comment in almost every solar electric related video i watch
Love your hair!
Nourished by solar panels.
Hi altE store
I have watch so many videos of you and get so much knowledge about solar power system. In February 2020 i am installing solar system in my home in Pakistan faisalabad. I have bought A class solar panels and inverter with net metering which will be use without batteries right now. Later on i will use batteries. Now the point is i am worried about the solar panels connection to inverter because in my locality there is no expert electrician. So can you help me out in connections.
fantastic explanation for 12volt &24volt pannels difference . thanks a lot . keep it up good job . super .
Thank you for the information I learned alot!
Great video Amy-Thanks a bunch.
You may want to update this video, besides things like 60 cell panels can charge 24v batteries.
Wonder why it worked for me as far as 24 V charging. I had one 170 watt 37 volt anel with a cheap eBay controller and it charge my 24 volt battery bank all Last summer.
Hi, I am planning on getting a 36 cell panel to charge my battery of 12V, but I am connecting 4 of such batteries in parallel to get enough current for driving a 250W motor, so can I use three of such 36 cell panels connected in parallel to get the out put (12 V 24A) that I need? And will the PWM controller supports this? Thanks for the video its was help full and cleared lot of my questions, I would be glad if you help me out with this, looking forward for your reply :)
Great, the 36 cell panel is a 12V panel, designed to charge 12V battery banks. If you need more than one panel, then wire them in parallel to increase the amps. To determine if your PWM charge controller is big enough for the panels. Look at the Short Circuit Current (Isc) of the panels you are using, and multiply it by the number of panels, times 1.25 for safety. So if your panels have an Isc of 8A, and you are using 3 panels, that is 8A x 3 x 1.25 = 30A charge controller needed.
It's a great explanation, very useful. Thx u.
Thank you, very informative. I wanted to ask, with the new solar transparency cells, are they the same voltage s as solar panels? Definitely appreciate feedback please
Thank you in advance. From Australia
Cheers.
Sorry, we haven't seen the specs for the transparent cells, so don't really know. It's important to remember that a lot of the cool new technologies you read about are either still in development, or so inefficient it doesn't make financial sense yet. But work goes on, they'll get there.
Hi, thanks for the great information, you said at 4:50 that it is not possible to charge a 24v battery with only one 60 cells panel, if the Voc is about 38V and Vmp is about 31V (so still over the needed 28.8V to charge battery) , what is the problem then?
While you technically can charge a 24V battery with a 20V panel, it is not a good option. When it gets hot, the voltage of the solar panel drops, so in the summer or any hot weather, you may not have a high enough voltage to completely charge the battery. That can cause the battery to be in a partial state of charge for months, which is not healthy for most lead acid batteries. Keep in mind a 12V panel has 36 cells, and a Voc of around 22V. So a panel to charge a battery voltage twice as high should have twice the cells and twice the voltage, thus the 24V 72 cell panels. You can see a demo of it here, th-cam.com/video/4hU6FUiFI2I/w-d-xo.html
I'm curious (don't know if you or someone else can answer) if I have a 100 ah battery and a 60 watt solar panel that puts out approx 5 amps would it be able to eventually put 100 ah back into the battery?
I'm just learning about this recently in preparation to add to an existing 90W panel I have on my 12v RV system. Where does the difference between monocrystalline vs polycrystalline factor in? I live in California but I intend on driving everywhere so from what I understand, mono panels are more tolerant of shaded sun than poly type panels. I have a very limited space to add more panels to the existing run. I'm wondering if I added two or if possible three panels for a total of 390w, would an mppt controller be of any use(I plan on replacing it due to the increased input)? I also will add 4 more deep cycle batteries(or some type of sealed battery, replacing the lead acids if I change the battery type) to my existing 2 for a total of 6. I will be using a computer on an inverter as well. Any suggestions?
+Maxid1 One of our most popular videos is on the differencees between mono and poly. th-cam.com/video/TCq0K3DlFdc/w-d-xo.html However, for such a small system as yours, I would not concern myself with it. The difference is going to be so small, just get whatever panel you can get that fits, don't worry abut mono vs poly. An MPPT charge controller will likely be able to generate more power for you, but make sure you use panels that are very similar to each other. An MPPT charge controller works best when the panels are similar. If you are planning on replacing your battery bank, I suggest getting higher amp hour batteries to minimize the number of parallel strings. It is much better to wire batteries in series than parallel, due to uneven charging and discharging of parallel strings. For example, it is better to wire two 6V batteries in series than two 12V batteries in parallel. Also be careful about adding too many batteries and not enough solar to fully charge them. If you don't have enough solar, you may end up with the batteries in a partial state of charge, shortening their life. I wouldn't go much bigger than a 400Ah battery bank with 390W of solar, unless you are going for days without using it, and you have multiple days to fill the batteries back up.
I have been watching all your videos to gain more knowledge about solar panel. I have a simple question. Let's suppose I would like to buy 30W solar panel, does it matter what solar cell series it is? since 30w solar panel is smaller power than all are available out there.
A 30W solar panel would most likely be a 36 cell 12V panel.
When the panel is tilted off square with the sun, its AREA is LESS; projected area,that is;
if you tilt it off 90º, having the sun hit on its edge, the area becomes ZERO,of course.
Where were you before I put up the solar panels?
Here, waiting for you to find us ;)
I REALLY LOVE YOUR VIDEOS.
THANKS
I like your explanations
Good. However, can the solar panel with micro inverter be operated in the night?
I'm not sure I understand your question. Will a microinverter work at night? No, it needs the sun. Newer microinverters can be used with a battery system allowing you to use the energy made at night. www.altestore.com/store/deep-cycle-batteries/lithium-batteries/enphase-energy-ensemble-energy-storage-system-p41457/#ENPENCHARGE10
over where I live the house apparently works with 125 volt... I guess that this would mean that I would need 5 panels of 24 volts... yet.. I wonder... because the house uses the common AC current, and not DC... so the current would need to be made AC... would I need those 5 panels or less??... how many batteries would be needed??... finally should I skip the batteries and connect straight to the main, (grid tie)??
You are correct that you need an inverter to convert the DC from the panels to AC for your house. Whether you need batteries or just connect straight to the grid is up to you, and what your goals are. If you are looking to simply save money and use less dirty electricity, then a straight grid tie is best, if net metering is available from your electric company. Different inverters have different requirements for how many panels they require going into them. You can see how mush solar is needed to offset a percentage of your existing electric bill with our grid tie calculator, www.altestore.com/store/calculators/on_grid_calculator/ If you are looking for backup power due to power outages from the grid, then you can have a hybrid grid tie battery backup system. Create a loads list of what you want to backup to determine how much power you need to store. www.altestore.com/store/calculators/load_calculator/ then go to the off grid calculator to determine how many panels and batteries you need. www.altestore.com/store/calculators/off_grid_calculator/?dwhrs=0
That was great. Thank you.
When I first heard about salt batteries, it was stated that they had to be kept at 700 degrees, which eliminated home use. In layman's terms, how are you doing this at ambient temperature.
Totally different technology. That is molten salt, this is salt water.
A few questions:
1. Can three 60 cell panels be wired in series (60v total) going to a MPPT controller going to a 24v battery bank?
2. If so, then what would be the upper limit of panel voltage going to the MPPT?
3. Can one MPPT accept parallel panel inputs of different voltages, e.g., one string coming in at 60v and another at 40v?
Thanks.
Answers 1 and 2 depend on the charge controller. Most MPPT charge controllers have a Voc plus temperature compensation of 150V. Those can take three 60 cell panels in series, even in the coldest environments, you'd be under 150V (38Voc x 3 x 1.25 temperature compensation = 142V). If you want to wire three 72 cell panels in series, you'd need a charge controller that can handle at least 165V, like the Midnite Classic 200 or the Magnum PT100.
#3 I am working on releasing a series of demos showing exactly that, they should be out over the next 2 weeks. Short answer, if wiring different voltages, but same amps, wire in series (if using MPPT that can handle the voltage). If same voltage and different amps, wire in parallel. If both volts and amps are different, it may not be worth the effort.
lol....no
i mean,it will work,but...not well at all..
3 panels of 60 cells give you 28x3 volts, or 82 volts !!! Danger!!! Danger!! 82 volts *DC* is NO kidding matter !!!! SPARKS will fly!!!
Any MPPT will ONLY reduce panel VOLTS
It CANNOT raise the amps of the panel, so, no point in using it here ( i mean, yes,but only a negative point..)
So, do not feed 82 volts to the MPPT,if it will only output 28 volts to the 24 V batteries,like you said
Instead,wire them panels in PARALLEL( around 22 Amps,MAX!!) and you can use a cheap PWM charge controller;
That is exactly the setup i have,works well.
Thank you , yes it is very helpful
Nice and useful videos sir
I have a question
If I gonna design a solar street light with 27 hours backup if the Load is 65watt and the Sun hours are 7h
Then:
1:what battery size do I need
2:what penal size
3:what inverter size
4:if I use two penal(2*150) do I need solar combiner
.
.
.
.
To figure that out, we need to know how many hours the light will be on. Let's guess 10 hours, and do the math. I also suggest you get a DC light so you do not need an inverter.
Solar: 65W x 10 hours = 650Wh a day. 650Wh / 7 sun hours (are you sure about that number, very few places have that much?)/.65 system losses = 143 watts of solar needed minimum. Let's round up to 150W.
Batteries: 650Wh x 1.125 days (27 hours) / 30% depth of discharge) / 12V = 203Ah 12V battery. 200Ah is close enough.
If you do use two panels in parallel, you can use a pair of couplers to combine them. See this video th-cam.com/video/9xsf_l_mCEk/w-d-xo.html
Good job
Hello Amy,
I have my inverter online but I made a small test to see what would be better two strings of 8 or 9 in series. While I was doing this I noticed that 2 of the panels have the VOC 42 while the rest only 40 or bellow. I bought them used at a good price. The Voc on the panel should be 44,4 V. They where set flat on the ground so i was not expecting more but I was expecting to have the same value. Is this normal? Out of 9 180W panels I only got 900 W(panels flat on the ground.). I hope I did not do a bad purchase on the panels.
+Adrian Cheudan That can be normal. Some installers will sort their panels as they come off the truck to make sure that they are closely matched per string. But don't worry too much about it. When calculating the expected output from a solar system, mismatched panels are factored in, so don't worry that 2 of them are 5% lower voltage, they should be fine. I suggest you also test the amps out of each with an amp meter and compare with rated Isc, but that should be don't with them facing the sun and at mid day on a sunny day. That will give you a good idea if the panels have a problem.
I am in the middle of purchasing a decommissioned missile base,,,, I have plenty of room for the solar panels and a big room for batteries . I want to convert the base to run off solar and wind power . Does ur company also do installation of equipment ?
altE only sells equipment, we don't do installations,
Really nice educative videos here!
Excellent stuff here.
very nice
mam can u tell me about 12 v battry and how to recmend solar pannel and which watts and which sirres
Hello Amy, Can i use a 60 cell panel (20V nominal) to charge a 12V battery by using a 12V PWM charge controller?
You will lose over half the power from the panel. You need an MPPT charge controller to convert the voltage down to the right level while increasing the amps so you don't lose power. With a PWM charge controller, the volts will drop, but the amps won't go up. You can see us try a 24V panel with a PWM vs MPPT. Same thing will happen with a 20V. th-cam.com/video/V2b7z2eTb5o/w-d-xo.html
Love your teaching
Do 72 cell panels have the 4000 Pascal wind resistance against upward lift like some 60 cell?
It depends on the brand. For example, the QCELL Duo panels do have the high wind resistance. www.altestore.com/store/solar-panels/q-cells-solar-panels-p41041/#HAN370QPEAK370M
Hello. I have a quick question. I’m getting a 6.2 KWh 19 panels LG Neon 2 panels. Paying about 16.5k with federal tax credit. Oakland Ca area. Is that about right? Or is it on the high side.
I'm doing a small RV system... using cheap lithium 36v battery packs in parallel. does the cell count matter if using an mppt controller? The mppt controller I found seems to indicate it's possible to charge input 12v-90v and output 12v-72v... but 36v batteries in a solar system are uncommon so I'm still not sure
60 cell panels are nominal 20V, so 2 in series is good for up to 40V. The Midnite Solar Kid can charge 36V pattery packs. But my question is, what will you use the 36V for? Do you have 36V loads, or a 36V inverter?
altE I do not have 36v loads. I'd have to use a specific sine wave inverter to get to 110ac and another buck converter to get to 12v for lights and some other devices. I got a good deal on some 36v battery packs made of 18650 cells since the hoverboard fad died. that's the only reason for going with a 36v system. I could also take the cells and build a 12v system but I was trying to see if I can save some work.
altE just looked up midnite solar kid. actually looks really good
Looks like you have a plan. There are some 36V inverters out there, just make sure they have one that does what you need for a reasonable price, and doesn't cost so much you end up paying more for the good deal. We run into that a lot, which is why I asked.
If you haven't seen it already, here's a video we did on the Kid. th-cam.com/video/bc4OiBT5hqY/w-d-xo.html
I have one 295 watt solar world 36v panel, could I use this with an mttp to charge a 12v or 24v bank? it was free and would like to make a little charge station for phones, laptop, etc.
Absolutely. That's a "20V nominal" 60 cell panel with 36Voc. You can use an MPPT charge controller to charge a 12V battery bank. If you are in a location where it gets hot, it will not do a good job charging a 24V battery bank, unless you got 2 in series. See more on charging a battery with a 60 cell panel at th-cam.com/video/4hU6FUiFI2I/w-d-xo.html
Is it possible to use 400 watt, 65-75 volt panels to charge a 24 volt battery bank?
With an MPPT charge controller, yes.
I think there is an error in your calculations. You say that a 72 volt panel can only use 11 panels in a system because 44X11X1.21 is max per NEC. But a 72 cell panel produces .5v x 72 x 1.2 or 44 volts AFTER compensation and 44V x 12 panels is still under 600VDC.
.5V is Vmp. You are supposed to you Voc for temperature compensation.
So Much Great Info! Thank You
I like your videos but there is not much info about the how to use 96 cell with inverters.
Excellent point. Because of the high voltage of 96 cell panels, they are usually used with either microinverters like Enphase IQ7X or DC optimizers like the SolarEdge P400. Using them with string inverters can have tricky string sizing, so is not often done.
very informative thanks
Solar panels must help hair grow! I want some
hi ammy.. i am having two 350w 24v solar panels and single 200ah Battery and mppt solar charge controller 40amp.. should I connect pannels in series or parralel to charge my battery and run some load on solar simultaneously?
series increases voltage and watts
parralel increases amps...
you only have two panels..in series it will charge your battery but if you gonna draw a lot from the battery you need to get the amps up
remember you have a 40 amp mppt ..dont exceed it..but you didnt say how much wattage your mppt is
dont exceed the wattage of the mppt.
so 4 panels of that size is about max for 24volt system
you can add 2 more if you want but dont exceed the wattage of mppt..
40 amp MPPT has a limit of
500 watts at 12 volt
1000 watts @ 24 volt
2000 watts @ 48 volt
@@starofeden9277 thanks.. net has joined the world.. i got the answer in a remote indian village !
@@jaswinderjohal2079 oh....ok.....so you got help somewhere
So to keep the heat down on your panels, don't Mount them on the roof of you're home. Besides you don't want to be walking on your roof, that protects your whole house stay off of it.
What is the best type of solar panel for high temperature you advice for Kuwait in Arabic culf
I'm just starting out... There's just too much to learn... Too many variables.... So I watched about 100 videos on starter systems...mainly 12 volt arrays.
I bought a 12v 100ah AGM battery and a 100w panel with a 2000/4000 Pure Sine wave Inverter and a HQST MPPT 20a charge controller ... Seemed like a good start but been watchin more and more videos and getting flustered hahaha now wondering if I have enough controller for expansion..
A 20A 12V charge controller can manage about 250W of solar.
Great info. Thank you.
Subbed for sure for a while now. I find myself watching this particular video several times now. I am simply trying to take out of this what I need and in the meantime understanding the full picture - history. Mainly, I am concerned about powering an off grid class C vehicle. I am pretty sure I want around 600 watts, 72 volts, to charge four 12 volt deep cycle batteries wired in series - parallel = 24 volts able to power a small deep freezer and minor additional needs.
So in summary, with 41 square feet to work with, can I just drive down?
Terrific. Keep in mind you also have the option of wiring two 36 cell, 12V panel in series to make the 24V. Sometimes that works out better space-wise, if you need to work around a skylight or AC unit. Also shipping a 72 cell panel can be expensive, as it has to go by truck. Another thing to think about is not overpowering the batteries. Most batteries like being charged at about a C-10 rate (plus or minus a couple), which means, for example, if you have four 12V 125Ah batteries wired in series/parallel, you would have 24V 250Ah. You should aim to charge it at about 25A. 25A x 24V = 600W of solar.
Come on by! We are here Monday through Friday, 9AM to 5:30PM. We don't have a storefront, but have some of our technical sales reps and lots of inventory here in Boxborough, MA. I suggest calling first just to make sure we've got what you are looking for in stock, and have someone ready for you. 877-878-4060.
We currently have a bunch of Made in USA SolarWorld 325W 24V panels in stock. www.altestore.com/store/solar-panels/solarworld-325-watt-solar-panel-sunmodule-sw325-mono-v40-frame-p11919/
Thanks so much! You take the hard work out of the researching!
Is this still relevant to 2018+ Technology?
Should I wait?