THANK YOU SO MUCH THIS IS EXACTLY THE INFORMATION I WAS LOOKING FOR. And you had amazing, super helpful diagrams to help a visual learner like myself understand! Your explanations are so clear!
This panel can put out close to 100 watts th-cam.com/users/postUgkxOqI2yqX0XVrhR2BMJciTWrHJpG8FhJyg when positioned in the appropriate southernly direction, tilted to the optimal angle for your latitude/date, and connected to a higher capacity device than a 500. The built in kickstand angle is a fixed at 50 degrees. Up to 20% more power can be output by selecting the actual date and latitude optimal angle.The 500 will only input 3.5A maximum at 18 volts for 63 watts. Some of the excess power from the panel can be fed into a USB battery bank, charged directly from the panel while also charging a 500. This will allow you to harvest as much as 63 + 15 = 78 watts.If this panel is used to charge a larger device, such as the power station, then its full output potential can be realized.
Actually this is not an "off grid" system. Not even if you use "quotes". It is a poorly designed manually controlled "AC Coupled Hybrid PV" system. Real AC Coupled Hybrid PV systems are 100% automatic.
Thanks for these videos, they are hugely helpful. We recently built a house in Sayulita, Mexico, and it is experiencing growing pains with frequent power outages. Located at the 20 parallel with 350 days of sunshine a year it is an ideal candidate for using solar. The power company has a monthly cap on electric consumption that when you go over the cost rate increases dramatically, and for the next 6 months. So, we are looking at all the solar options, and your series of 3 videos have helped me understand the options and issues. Thanks.
I really enjoyed watching this series of videos and your solar setup. It is frustrating watching other channels invest tens of thousands of dollars for an off grid system when their property is capable of being grid tied all to avoid a power bill. They invested 40K++ (in parts alone) in an inferior off grid solar + generator setup to avoid paying 10K to tie into the grid. You basically validated all the points I tried to make... including investing their money in the sock market!
I really like the illustrative and descriptive information that is so easy to process, even a child can understand, like Einstien once said. If lecturers in school can start by explaining the process before the technical things.
I am very impressed with ur system and the way u are able to explain it. very often ther is the lack of logic thinking and u are gifted to do so because of studying the material.
When I got solar 6 years ago, battery systems were just too expensive and would never break even. Now though, they're just about affordable/economical and I'm looking to add one into my system too. Your video helped a lot, thanks!
So very well and clear explained. Excellent how you correct, make yourself more understandable by editing your voiceover afterwards. It is pleasing. Everyone understands that. Thanks!
If it has issues starting heavy loads, you can put capacitors on those loads. That would help get over the initial startup draw. That would be cheaper than running two inverters.
Excellent video. Very clear and thorough. I've also come to the same conclusion as you regarding AC-coupling. In my case, I will be using microinverters as solar AC source. According to Schneider, if your grid is out, their XW+ inverters cannot regulate the current used to charge your batteries. This applies only to AC-coupled systems. They say lead acid (like yours) can handle this 'full on' charge but other batteries like Lithium, cannot. The next time your grid is out (or as a test), see if you can measure the current being dumped on your battery bank. It should be ~140A regardless of state of charge.
It gives the amperage readout on the control panel. The amperage does vary some, between 120 and 180 or so, depending on the charge state of the battery bank. It also has a temperature sensor for the batteries that will stop or slow the charging if the batteries get too hot.
This is one main issue I see with the system in the video; AC coupled system with the "Grid-Tie" inverter (GTI) operating/configured as per Grid code can cause: 1. Tripping of the Hybrid Inverter (or both) on low load and high sun conditions (as the GTI try to output a lot more power than required by load conditions - including battery charging), or 2. overcharging of batteries; the Hybrid inverter will not be able to regulate the charging current (from the GTI) as it is not communicating with it - this can shorten battery life, if not damage the batteries - battery dependent) Typically, in AC Coupled systems operating off-grid, where there's no direct communication between the inverters (maybe because of different brands, or simply the option is not available) the GTI inverter should be configured to operate in "Off-Grid" mode, whereby the Hybrid inverter can then "communicate" and control the output power of the GTI by varying the AC frequency (and via Frequency-Shift Power Control (FSPC) for SMA, Active Frequency Shift Power Curtailment (AFSPC) for Schneider or in this case, Power Control Option for SolarEdge); note however that the default "Off-Grid" mode may not comply with Grid code (adjusting frequency range, and adding an additional anti-islanding relay can likely solve this issue, to comply with operation with Grid present). Otherwise, for FarmCraft 01's situation, the SolarEdge StorEdge solution could have proved easier to integrate.
I have always wanted to find out if a gridtie inverter can produced power to an inverter but today i know it, all thanks to you. Big ups and keep it up. Thank you
Hey Farmcraft, Nice work. That's a great system. However, there is an issue with your battery bank that needs correcting. You have three strings of batteries, and your main DC + and - are coming from the same string. You will balance the current between the three strings better if you have the DC + coming from string 1 and the DC - coming from string 3. As it is, you will use more current from the string on the right, and so your batteries will age at different rates.
@Paul D - Maybe the Schneider Conext inverter has built in functionality in it's charge controller though which would alleviate or minimize that problem?
Good point but, I don't think the few millivolts drop in those cables is going to be significant. Imbalance in the capacity of the cells is what causes failure... A chain is as strong as the weakest link... In series cells the one with smallest capacity gets "bullied" by the others. Overcharged at the top end and depleted or even reverse charged at the bottom end.
Brilliant video. Superbly explained. This is why I love TH-cam. Not always, but occasionally a great source of information as was this case. Thanks for sharing
I would disagree on many items in this design. I do think FarmCraft101 has some great diagrams and teaching methods, but it lacks trade smarts and code compliance/safety. There is no reason to re-invent the wheel here. I hope people don't just assume all inverters have this "multi inverter" feature, which is actually for the same models w/ proper distribution panel. As Tofulnc says, the XW6800 hybrid could do it all. Here are my safety/code concerns: 1.)MC cable for HVDC ... not allowed in most states! Use PVC, or EMT. 2.)16.8kW feeding into a 200Amp panel .... almost double the allowed 20% over current by code. 3.)Where is the DC combiner for 3 strings. I believe you said 1 wire for DC run.(actually 3 but need 5) 4.)Why is there a label for AC disconnect on the DC run? 5.)AC couple is not ok for just any brand inverter. Those frequency control funtions are for 2-3 same size and brand inverters with proper distribution box. 6.)Is that a suicide cord being used ... on the gen run .. and manual charge? Way not ok! 7.)Guessing that manual xfer would need a separate lockout box too ... if it was allowable. 8.)I did not see a battery breaker or other DC distribution on low volt side. Bigger bank and cable size could help start large loads using all of the 13kw startup power (maybe 10sec?) from the xw6800. 9.)Proper clearances are not maintained on XW6800 10.)No mention of grounding and reasons for it are a big missing part of safety w/ 380VDC runs in a DIY video. 11.) I have to assume that this addition is without a permit. I feel it is to the advantage for DIY to use inspectors to help make installs a bit more safe, and not void your home owners insurance. 12.)I would never recommend DIY for backup/offrid if the owner did not install the grid tie setup! It is way more complicated and dangerous! Ok ... not to worry. I am not the inspector in your county! But this is a video to help people learn ... right? Why not show a safe more simple approach. Here is are some things missing in your "retrofit strategy". 1.)Cheap solution is rewire array yourself for 10 of 3 panel strings of 100-150VDC. 2.)Put the proper fused DC combiner at the Array. 3.)Pull new wires if needed on DC run. How much can a DIY 300ft ditch and conduit run for a worst case scenario? Not the $1000 to $2000 extra for HV CCs. 2x 80A HVCC would get you to 8.8KW PCT or 10k DC STC if you do not want to oversize array to inverter. 4.)Bigger battery bank, proper batteries, larger inter ties/homeruns, and large xfer switch solves the startup problem. A gen along with gen load balance can also work if that compressor is really needed offgrid! Symmetrical taps would also help! Yes, high current is different than normal wiring. 5.)Realize that you do get 3300W per XWMPPT60 CC, and could go with just 2 for a 9.2karray. Yes ... you can over size an array to inverters or CCs and they just de-rate by firmware for safety when needed! It is completely allowed by the manufacturer and codes. If you want to save on equipment ... this is a place! Panels are cheap! This type of over size of 25% (9.2k x .85 PCT factor = 1.25 x 6.8k) . results in a loss of only about 5-10% depending on climate since peak power only occurs on cold days near noon time. 6.)Realize that a large manual 200A xfer switch could just be a "high power grid tie mode", and then 99% of everything else would just be automatic with the 60A XW automatic xfer. This solves your critical loads problem. Using appropriate size battery bank/ and oversized inter ties will help on motor starts. Does that large compressor really need back up ... instead of a little cheap spare? Running one or two new dedicated circuits for an item is not typically that hard. Making it look good can be hard! 7.) Have to say the already wasted money here is the original system with "optimizers". I would guess the installer got a closeout deal ... after hearing the $1200 price for the 10k inverter .... which was originally more like $2000 plus $2000 more for the optimizers. They are just not needed on a single plane array. Most panels have "bypass diodes" that help minimize losses when a random panel fails or is dirty. Maintenance and monitoring is even a better solution. These, and micro inverters need 4x as many weather tight plugs, which are the most likely part to fail on the array. What a longgggg comment. It helps me stay in design shape when not installing so many systems! Maybe some one reads it ;-)
@@koisolare1266 I read it. I'm impressed. Clearly you know a lot about it. Problem is: It is hard, very difficult to understand without schemes. Do I understand you well? The system of FarmCraft is not safe or not as safe as it should and could be? How much would the system cost if it was setup your way?
@@guzziventure1750 A standard XW6800 system with smaller battery bank is about 10k$ plus another 10k$ for rewire, trench and labor (PV and ground mount additional cost) A general rule for battery backup is 2 to 3x the cost of grid tie. It makes much more since to get a gas/propane backup compressor/gen if you really need that backed up. Battery backup is always questionable if you do not use it more than a week in a year.
@@beforebefore That's great as long as he is around to manually switch - what happens if he leaves this world and his family decides to sell. How does the new buyer deal with this setup? Not that I'm against this, just saying yes it works for him, but could be a problem for someone else since it's set up for manual operation. I have looked at property with home designed systems, some are easy to see proper operation and some are not. Would hate to hear that some lineman was killed because someone didn't have the background to properly operation a system.
@@Bigreddogs2007 The manual grid disconnect(s) makes it physically impossible (or at least impossible without modifying the panel to remove the disconnect) to feed power from the battery backup to the grid, meaning no linemen will ever be endangered by this setup. This is a common approach used all the time in generator installs (he mentions that the manual disconnect on the house predates the battery backup and was originally installed for generator use. The battery inverter, from the perspective of AC loads and the grid, is really no different than a generator, so this safety device is well suited for the task.
Glad to see you used that type of batteries, lithium ion are very compact, energy efficient but are to dangerous for inside residents and cars, coming out with several new battery types like sodium ion which is approaching lithium ion but are A little heavier but much safer and can even use the same manufacturing lines, the future is a little brighter, like your videos, keep it up.
One question: When your transfer switch is off (e.g. when the grid is working), how do the batteries get charged? Maybe the "hybrid inverter" has separable AC in and AC out?
Yes, hybrid inverters have separate AC in and out. Some hybrid inverters have 2 AC outs one for regular load and one critical load as explained in the part 2.
glad he included the disadvantage of the two inverters not having a deticated control line between them but curious that he did not mention the power loss to heat from converting DC>AC>DC for charging the batteries via solar. may be minor but still significant.
You do know BYPASS DIODES right.. So a Guy like Wood Seem pretty stupid If he fell for the SERIEL PANEL'S WITH SHADDOWS WIL SHOT THE WHOLE STRING DOWN ... YOU CAN'T SERIUSLY CALL YOU SELF THAT .. AND DONT KNOW. THIS ???? IT Will not shot down the whole string Just bypass the shaddowed panel Same reduktion in watt as paralell But No freaking shut down ... Let's her hos skat you aculey are .. Doe's BYPASS DIODES. Bypass AFFECTED shaded areas on PANELS True Or False !!!!
Hmmm got an email from Kenneth Schultz . but his Channel doesn't have any content. I'll still answer this. but First lets read: Kenneth Schultz to Me... You do know BYPASS DIODES right.. So a Guy like Wood Seem pretty stupid If he fell for the SERIEL PANEL'S WITH SHADDOWS WIL SHOT THE WHOLE STRING DOWN ... YOU CAN'T SERIUSLY CALL YOU SELF THAT .. AND DONT KNOW. THIS ???? Me to Kenneth Schultz... You're Correct on the Bypass Diodes. Monocrystalline panels have those, if part shading will shut off that string. Also if Light is not distributed evenly and overheating. We experimented in a classroom with Simulated Sunlight. That panel didn't want to cooperate, 2 LED lamps were being focused in the middle of the panel and Zip, Nada. Then we added more LED lamps a total of 6 that shed light evenly and Voila' panel worked more efficient. First try the panel did produce voltage but wouldn't turn on the MPPT charger. Second try with 6 lamps it did what we intended to do. (wish I could post pictures here) Third try, we changed panel from Monocrystalline to Polycrystalline and it worked with part shading. They both have Pros and Cons. Yes we had micro inverters then we used optimizers. I'm not offended by your remark, why should I. it also serves as a learning tool for others where everyone benefits. I have installed some panels on RV's but I won't called myself a professional on that field. I've seen some installs that make me want to go deeper into that field. As I stated I admired FarmCraft 101's video.
Your videos are amazing and have helped motivate me to pursue an area of keen interest, physics Especially, since I know awesome DIY projects are so doable. You really ought to have a skillshare account, to help spread your talent for teaching. Great humor in the videos, find myself laughing a lot too.
Another negative for using a high voltage battery charge controller besides cost, that is not realized by many system designers, is the ripple current that is placed on the batteries. The Hybrid inverter DC input current draw is based on the AC sinewave load profile, meaning the current into the 48 vdc input to the Hybrid inverter is half sinewave pulses, like a full wave rectified sinewave. The 48 vdc from the high voltage PV charge controller is a more uniform DC feed with DC output voltage based on the charge state of the batteries. The batteries now act as a filter capacitor to supply the peak sinewave current and reverse DC current to momentarily push current into the battery at AC zero voltage crossings of the sinewave AC power. What this means is the batteries are subject to continuous pushing and pulling of current at 120 Hz rate which shorten their live span even though there may be no net average power draw from the batteries. Your Hybrid battery inverter was obviously added by you after the grid tie system was installed and approved. Your installation on the Hybrid addition would not have passed inspection. At minimum I would recommend you cut a piece of plywood or drywall and cover up the exposed battery terminals to prevent accidently dropping something conductive on them. Most codes do not allow batteries to be located directly below electrical panels due to potential hydrogen outgassing by batteries, even if using sealed lead acid type.
Very nice system. My questions are -> 1. How do you charge the batteries when the grid is on. It seems that the Schneider inverter will be totally disconnected. 2. What happens to the Schneider when the grid is on? Do you turn it off manually?
07:05 If I am not mistaken, having two inverters will not double your energy production which is limited to the production capacity of your solar system (30 x Wp of each panel) and because only one inverter is connected to the solar system. Thus you don't need the first/old inverter, which is consuming energy. Thanks for sharing information about your solar hybrid system.
You are not completely mistaken, but you are probably confusing energy and power. Of course the total offgrid energy is limited by the solar production, but the instantaneous power available at any one moment is limited by the inverters, let's say one driven by the panels and one driven by the batteries. So having double the watts available from the two inverters is difference between being able to use your high current devices for a short time (ovens, saws, dryer etc.) or not being able to use them at all.
@@craignels No confusion! But one inverter can do both (I think he is equipped with sophisticated inverters) dealing with solar panels and batteries. Hybrid inverters play many roles, i.e. regulator, charger and DC/AC converter plus reinjecting the surplus of energy into the grid. Unless the intention is to secure the installation using two inverters.
@@m.bouanane4455 The intention is not to secure the installation. Rather he started with the grid tie system as a given. Then later wanted to add battery backup. He could have replaced his existing 8KW grid tie inverter with a 16KW hybrid inverter, but instead decided he would just add an 8KW hybrid inverter to his existing system. The key idea he's promoting is when adding battery to an existing system, AC coupling is the way to go.
The Sungold Power TP6048 takes the place of both the hybrid inverter and the grid tied inverter in your diagram at 1:51, right? Do you hook both the A/C input and A/C output to your system, or do you just leave the A/C in unhooked?
0:28 I have a small 300w-30V grid-tie set-up, will adding a charge controller and batteries work this way? I just want to have some more storage to kick in at night as we usually consume less power than 300w.
Very cool setup. Most real time clock chips use a crystal oscillator and would not be affected by the input frequency changing. Curious what devices you found in your house that are affected by input frequency.
You should share this video with everyone in LA and Northern California that often have solar arrays and now have the electric company turning off the grid to reduce fire risk. This would be MUCH appreciated. I will post it to many friends in Santa Rosa.
Slick. I work with commercial VFDs for motor control etc. A good surge/lightning protection system is good insurance..especially (and I don't know why) in a rural setting. They used to call them a TVSS but there is a new terminology now that escapes me.
BIG THANK YOU !!! I am studying how to insert a [GRID-TIE-INVERTER] to my off grid solar/battery setup. (Just how you showed in your slide) Right now im running just a circuit from my house off-grid (1 room and the fridge) But at 9am.. Batts will be at 14volts ! So rest of the day im just throwing away the rest of the captured energy ! My setup is smaller but I guess the same rules or logic applies. Again, thank you. (Surviving on Solar Energy after Hurricane Maria in Puerto Rico.)
Please explain how to handle if production is high and load is less battery is full. i have 2kva home UPS sign wave with 2 battery. I would like to add a 3kva solar using micro inverter. Here no grid back feeding mechanism. Presently grid current is passing through my old inverter to entire house. I am not willing to throw out my old inverter for a hybrid and not much space for a big inverter so micro inverter is the only possible way. How can I prevent over production and blowing out my old inverter in low load and high production sunny day?
I was like you, wanted a way to use my solar when the grid is not connected, My solar system is on my RV, i installed grid tied invertor system because they are far cheaper than off grid setups, plus i wanted the ability to use it when not hooked up at rv parks and boondocking. So i use an old 1500 watt invertor combined with an interlocked circuit that i plug into the system running off the RVs 12v battery system, which pumps 120v into the system and tricks the grid tied invertor to allow me to use the solar. I only have 2 batteries in my battery bank, because i invested a bunch of money into batteries 6 years back and after 4 years over half the bank was giving me issues and since they were out of warranty it was a costly expense. Now i just have 2 high quality LiFePO4 batteries and use generator power when in dire need of power when no solar is available. The load on the 1500 watt invertor is only a few watts as the grid tied invertor overtakes the system. Before someone ask why i didnt just go with an offgrid system, i spend most of my days at RV parks with electric from the grid, but they charge you a lot for electric at many places, so with the grid tied system i can supplement my electric while at rv parks with the solar system. Most RVs at parks these days have all these solar panels on their rigs and none of it is being used while plugged into the grid, just letting the solar panels collect dust. also the solar panels on my roof ended up acting as a solar barrier from heat, after i installed the panels i noticed the RV doesnt get as hot and uses far less power running the a/c system to cool the RV, because the roof isnt being heated up by the sun anymore. I have solar running the entire length of my RV with an angled deflector upfront keeping the wind from going under the panels while in transport.
You are correct that the inductive compressor motor takes a lot of juice to start up, often 4-8x the standard running amperage. But most compressors are built with unloader valves. When your compressor gets up to pressure, you will hear it shut off and you'll hear a hiss of compressed air released. This is the pressure coming off the compressor head so the motor doesn't have to work against it to start up the compressor. Interesting video.
You have a great system there. The only thing I can see that you might consider changing. Is the battery Bank load side wires going to the inverter should be pulled from either corner of your battery Bank. The way they're wired now it would pull from the first string where they're connected. Just move either the positive or negative to the other end. This would make it act as one big battery.
With that being said, a charge controller output would go to the opposite corners of your battery Bank. That makes the input and the output run through the batteries.
@16:28 The load side conductors are on the same string. Although their in parallel, it will pull from the closest set first. So, your first string will take most of the load. I would pull from either end for your load and the opposite terminales for you line in. This will act as one big battery this way. the line in has to run all the way to the other end for the load. (not being a smart ass) Think about it. It makes sense. Hope this helps. I'll try to find some links to help out. Your not wrong but I think that it might cause extra strain on that first set.
Hi Farmcraft I have the solargain as well and I actually bought a seperate solar panels through Ebay with seperate charge controller and using lithium battery 48 volts which supply all my garage needs using 8kw inverter and essential home needs if grid drop down
Good video on AC-Coupled Solar setup. However if you know you would like to have battery backup as a requirement for the power system for the farm or house, It would be more economical for you to consider the solar PV systems from OutBack power. The one inverter / generator charger does it all in one unit. The whole system only has 3 major components the panels, the battery charge controller and the inverter. If you generate more power then you use, it will push it back to the grid, IF the power grid fails the inverter will power the house, off the batteries . In the event of low batteries, it will turn on a backup generator to charge and power the house.
Yes, that would work fine. Careful if the busbar is not insulated. Even with my insulated wires I'm careful not to drop anything metal on them. Could be an exciting short circuit.
One thing that I would like to see you do is to put those batteries on a shelf system so you can get them off your floor. The risk of something or someone falling on them is there, and a wall mounted system would be safer. The way you did the battery control with those inverters is good, and I would do exactly the same if I was in your situation. Spending more money on extra solar controllers is really no point when those inverters does the same job for less money. Great system without using tons of money.
I live in a small.... Crap i forgot the word for the house with multiple floors we learned it literally on the first english lesson.... house thing on a dense city area. I have a balcony, but too small to put just about any solar panels on. And the grid is just about never down. Or more accurately it's down a few times every summer, but gets fixed usually within half an hour. So. The point is. I have no practical need or the possibility to use anything i learn from this video. Or the other solarpowervideos i did watch the parts 1&2 and plan on watching that invest thing video too. I enjoy this. For no reason other than learning practical but unpractical things. And you never know i might move somewhere someday where i'll have the need for this.
So if your battery inverter never see line power how do you make sure the battery are changed when the power goes down because you turn the grid off to turn on your battery
Transfer switch .. either the generator kicks ind or battery Goe's until power is to low Then generator KICK's ind Chardged BATTERY run hous until power comes back
I have a grid tied system with an emergency power generator that has a whole house ATS service rated transfer switch to operate everything when the grid is down. And was considering adding a battery bank connected to a separate inverter like you did.
You can modify shop machines to work with low starting current. An unloader solenoid valve on an air compressor will dump the pressure at the outlet, and it will start easily. This is also possible with air conditioning but is more complex because you can't release the system pressure to the atmosphere.
Your explanation of the two Banks communicating via frequency, I can put a meter on my outlets right now and they will fluctuate from 55 to 64 HZ depending on what the atmospheric conditions are outside. I've even measured it going down to 51 Hertz during a thunderstorm. So how does the brainbox no what is a communication and what is a natural fluctuation of frequency on the power grid?
well explained...I do have some Qs for you. First I have an existing grid tied Sunny Boy solar system of 2 strings of panels totaling approx.12kw. I have a 48vdc 15kw 120/240 split phase pure sine-wave inverter/charger with no MPPT solar charger with 640ah battery string. The inverter manual say's The 15000 watt inverter features Dry Contacts Providing Frequency Switch Between 60Hz / 62.5Hz as the secondary charge control of on grid inverter. It can control excess energy from the grid tie inverter when the battery bank reaches a voltage within the manufacturer’s limit. To accomplish this, you can use a voltage-controlled relay to close the dry contact to switch the output freq from 60hz to 62.5Hz, shutting off the grid tie inverter system temporarily. The paragraph end there with no explanation as to what I can do with that temporary shut off I want to set up the A/C coupled system, I am not sure what I need at this point. Do you have some suggestion or maybe a good source in which I can better educate myself in this area...any help is greatly appreciated.
I was thinking using overlapping systems. One completely off grid powering certain circuits in the house such as all lights and some power circuits full time but with a 3 way changeover switch through a sub board. Possibly using a victron inverter charger..
HI. Great system. Have you changed the battery connection on either the Pos OR Neg yet ? Eg: Pos on Row 1 Pos Terminal Neg on Row 3 Neg Terminal . This will increase the life of your battery system. The load will be balanced. The amps from each row will be the same. At the moment, (as shown in the video) Row 1 will provide more amps than Row 2 and row 3 will have the lease amp draw. Batteries will deteriorate at different rates. . . . . Simple fix. . . . Move one cable only..... Good luck....
Hi Farmcraft101. Just seen this good video of yours for Ac Coupling to add battery storage to an existing solar Pv system. The system video is great and well explained. There is however one thing I have noticed as you were showing the way your batteries are interconnected in the battery bank: I notice that the battery bank negative and positive cables leading to inverter, are terminating on the “same side(edge)” of the battery bank, which is not supposed to be the case when you have more than one string of batteries connected in parallel in a battery bank. The two cables (positive and negative) leading to the inverter must terminate at opposite ends of the battery bank. This ensures that each string of the eight batteries passes equal current during charging and discharge. (I don’t know what I’m explaining going to come out clearly without a diagram to illustrate, but I hope you grasp what I mean). In the current configuration you have, the back string (closer to the inverter), passes more current than the middle string, and the middle string passes more than the front string (near the where you are standing in the video). So, front string has lowest current, middle string has medium current and back string has the highest current. The reason is as follows; the back string has shorter path and thus lower electrical resistance; the front string has the longest path and thus higher electrical resistance; the middle string electrical resistance is higher than back string and lower than front string, The magnitude of currents drawn from and fed to battery banks by inverters are very large and therefore very small differences in resistance in the electrical path passing these large currents have a very large effect on battery chemistry as time passes. Initially, since all the individual batteries are freshly installed, you will not notice any effect, but aa time passes and days turn to weeks to months, your battery bank will start aging unevenly with some batteries aging faster than others. That may surprise you, but the reason is; the uneven(unbalanced) currents passing through the three strings over time. In short, the string passing higher currents than another ends up being cycled more than the other, and battery age is all about cycles. If there was a way to attach an illustration diagram, I would have given you a diagram to explain the recommended method of connecting the two end cables to a battery bank with more than one parallel strings.
I think the distance of extra cabling from each parallel battery string is probably negligible, considering how close the battery strings are (right next to each other), and also the gauge of those terminal wires (very thick, minimal resistance). Thus the difference in path resistance for each string is probably quite negligible for this case, in my opinion.
NICE! I have a 7.8kW grid tie solar system. I was wondering how to get the solar power to be usable during outages. I did not go to the 'solar wall' when I put the system in three years ago as it didn't seem financially sound at the time. My solar has made my electric bill $19 / Mo except for Feb/Mar/Apr. The house is currently 'all electric' as built. As I replace resistance heating with propane, that will change. I am now putting in a 25kW diesel genny in my shop and it will be hooked to all buildings on the farm. I am going to build in auto transfer to control the switching over during outages. This system will provide backup to two separately fed, two utility meters, so it will require two ATS systems, easy enough to do. I am still going to, experimentally, look into a battery system like yours. With the auto transfer system I am building, tying that in would be easy. I always wanted to do a wind turbine, but they are being put in the shadows by PV. Way too much maintenance required for the benefit at this time. Thanks for the excellent video, and thanks for sharing the knowledge and experience. The technology changes as we speak... Now Subscribed.. Michael in CO. I should have read some of the comments before I commented... You just have to ignore some of the breathlessly uninformed when they fire up their armchairs. Whew!
I watched all three videos in this series and I found it very informative and it answered several questions I had while looking into PV cell installations and as such I gave you a thumb's up on each :) The battery backed-up system is "obviously" the preferred technical solution, but I'd say that it would bump up the overall price of your installation by several thousands of dollars, thus extending the period over which you would break even on your investment. Also, you failed to mention that each "component" of your installation (the inverter, battery charge monitor, panels, etc) has a limited lifespan. At best each device will slowly degrade in efficiency by a few percent per year, meaning there will be losses in power transfer (some of the produced power will be lost as heat, or batteries will be charged less). Worst case one or more components of your installation will simply "catastrophically" fail and will probably need replacing rather than repair. Safety wise I would not count on a 8.5 years break even period but rather a 10 to 11 year break even period just in case one or more components will EOL on you prematurely. In other words you're looking at a much steeper investment initially (or within the projected break even period of 8.5 years). If you intend to keep on living in your home for longer than 10 years after installation of your solar system, however, having a solar panel system (even with battery backup) still makes sense, notwithstanding possible degradation issues
We also went through this calculation when considering our setup (and decided against battery backup), you need to add in interest, ie if you invested the money instead of buying the extra equipment there would have been a return, and, over 10 years that may be quite large.
7:25 You talk about starting your 5HP compressor. I need some advice. I have a 4kW hybrid inverter which blew up while using my 3500W shower heater when the sun was down and we were on grid power. The inverter is set to shut down when the sun goes down so it can save the batteries for when we have our frequent blackouts. I'm just the consumer. I know very little. My installer is taking no responsibility and neither is the manufacturer. My question is: Do I spend $1400 to replace the main board in the inverter or should I buy a better inverter? System: 18 x 280W Maharlika PV panels Must PV3500 Inverter 4KW~12KW 8 x 12V 200AH 19.2kW Battery Storage System
If the inverter is under warranty I think it should be replaced for free. What are they telling you is the reason for failure? You really shouldn't be able to "blow up" an inverter. I don't know anything about that brand, but if you try to draw more than the inverter can put out it should automatically shut down, protecting itself from overload. If the battery voltage drops too low, it should also shut down. Either it was installed correctly and then the manufacturer should cover their inverter, or it was installed incorrectly then the installer should fix it. But I guess if it was installed correctly, and the manufacturer is not covering their product, I would say get a different inverter. They aren't cheap, but the Schneider Conext inverters are nice and they stand behind them.
FarmCraft101 , thank you for the response. They say the main board blew because too much draw from the house, mostly the instahot water heater, which they say could have spiked at over 4 times the rated 3500W draw.
That shouldn't hurt a properly designed inverter. Sure, maybe you were trying to draw too much current, but the designers should account for that possibility and put in overload protection. I mean, what if you had an appliance go bad and short out. That's a straight connection from hot to ground, and will pull massive amps briefly. My generator has a breaker for that purpose as well.
You've confirmed my own thoughts. We have a generator also, a Honda 2500W, and we've overloaded it several times. The breaker flips and no damage done. I opened the front panel, thereby cementing my decision not to repair this inverter, and a gecko was in there smiling at me. I did not see a fried gecko in there, but I couldn't see everywhere either. Definitely a possibility. As much as I would like a Schneider Cenext inverter, I'd need the 5.5kW and it's way out of my price league. Not to mention, the shipping to the Philippines would be over $1000. I haven't decided yet which inverter I will go with. Thank you again for your help.
You are a great teacher if I was able to (mostly) follow all three of these videos thus far. My question for you is are you still able to “sell” extra power to the grid when you retrofitted the batteries to a grid tied system. I watched this twice and did not find the answer to be yes. That doesn’t mean I’m right, and I’m hoping I’m wrong and you just didn’t address this option during this video. I know this is a few years old so I hope you are still responding to comments. The tax credit drops this year from 26% down to 22% next year so I’m hoping to figure out if it’s smarter to start with the less expensive option now to get the better tax deduction this year, and as I have more money in the future add on like you did. Thanks for all your great videos and sharing your vast knowledge !
A very good video. We have 20 panels and a maximum of 5 KW out put but we get at peak times about 4.5 KW of power with no batteries yet and on the grid. We do have an an advantage we live in a very sunny and warm climate. It has been only 4 days since the install and after a few years consider a second system for providing energy at night and powering the grid. That would mean an extra 10 panels and Thailand has stated that they will have a buy back system in place this year. Depending on what they offer I will think about adding panels. However we are almost paying nothing now as I have taken meter readings every day and if after 30 days the power is = then we should pay 90% less the next month for the PEA electric bills.
very good explanation (so far the best i've come across) but what you did not mention is that, without a transfer switch (or killing the mains breaker) power will flow from you PV system to the transformer on your power pole and then try to produce 7200v into the grid (transformers are bi-directional) this can kill a lineman working on the transmission lines and it will burn out your batteries or generator which will give it there all trying to produce the tremendous load called for by the transformer. that is why you never connect a generator or batteries to your panel without an air gap to the transformer on the pole outside your house.
Great explanation of the different systems and how they operate and the different components within the systems and all the rest. I have been trying to learn all this stuff for a while now and you sir just explained all my questions in one go Bravo! and thanks.
Nice system. Just a few month ago I was in a similar place as you. I ended up going with a solar charge controller because my gridtie DC voltage lined up with the battery bank and I wanted the inverter to keep running in the night.
Hello. your video is very interesting. I would like to know if it is possible to use a pure sine wave converter 12v 220-240v instead of a hybrid inverter. thank you very much.
Another option that is also AC-coupled, is a Victron Multiplus or Quattro inverter. You can put the SolarEdge inverter on the output of the Multiplus. It works the same way, charging the battery from the AC output of the PV-inverter, but you have the advantage of an automatic changeover. The grid is connected to the input of the Multi, and if the grid fails the Multi disconnects it automatically and powers the output, allowing the PV-inverter to continue working. It also supports a feature called ESS (Energy Storage System) that can in some cases control the PV-inverter (doesn't work with SolarEdge, SE doesn't support SunSpec model 123 in their implementation, but does work with Fronius) even while tied to the grid (ie when frequency shifting is not possible).
A midnite solar 250 charge controller will give you enough to run your whole array, one per 10 panels and eliminate the gridtied inverter. You would not have to manually manage your system. Lithium batteries are also awsome over lead acid, I made the move and loved them, no more smelly sulfur and watering, they also maintain a constant current under load unlike lead acid .
The most efficient way to get 220V or 110V ac should be to configure the panels to a high enough voltage so that when alternated with the most simple electronic circuit possible (transistor array on a signal generator) the result is the voltage you are trying to achieve. Obviously you want a bit extra for the times the sun is slightly overcast or not perfectly aligned. But basically this is why all grid tie inverters only start working around 110 - 150V DC and can often work up to around 400V DC. There should be an optimum voltage so it is good to aim for this voltage when building the array. Noting that you are limited by any panels that may be working at lower power levels when wiring in series (due to damage, smaller panel size or unbalanced strings). One thing i would like to say is that for most people they are better off using "thin film" panels (if they have the space and money), other wise solar tracking or a longitude near to the equator and a guarantee of many full sun days throughout the year are necessary to really benefit from mono and poly crystalline panels. Thin film are also great when partial shading might come into play due to unideal installation limitations.
Great explanation but I'm still slightly confused on one point. If the grid is on, how does the battery inverter get power to keep the battery charged? I understand when the grid is down, the inverters are connected through the panel and the interlock.
Thanks for your vides and detailed explainations. They helped me better understand the various system configurations (and complexities). You could definitely have (and maybe do by now), an automated transfer switch (to switch to battery bank when the power goes out). Your power probably doesn't go out much there. But around here the power is shut off every time the wind blows (over maybe 23mph or something?) due to wildfire risk. We went through one. 1500 of my neighbors lost their homes. But being without power for what has been in rare cases 5 days at a time (and 6 weeks during the wildfire), has been an inconvenience to say the least. The power has gone out here almost every week at least one day (and sometimes several), as they are currently [finally] upgrading (and replacing) the distribution infrastructure, and have to shut off the power to do so. I'm currently trying to build a system (on a very limited budget and with limited knowledge of Solar Systems or electrical in general). It is difficult to say the least, and will most likely be off grid (even though Grid tie systems now are more technologically sophisticated/ capable). I don't really have the finances to hire an electrician and do everything to code/ get inspections, etc. (of course it still has to be safe and not backfeed, etc.). I bought a hybrid inverter and 30KW/h LifePO4 battery bank (still sitting unused) at this point.
Very Interesting... just wondering a couple things that aren't clear. Where does the power go when it's a clear cool sunny day (=high watts!) and the batteries are fully charged, and there are no loads in the home? I'm pretty sure the 'frequency curtailment' or frequency shifting as it's sometimes called, is outside of the string inverters intended design limits, and voids most string inverter warranties.
14:21... Ok... question! How batteries are more easily/faster being charged? Through AC voltage from a smart off grid inverter, or through DC voltage from a charge controller? If anyone knows...i would appreciate an answer!! Thanks!
You can get Hybrid inverters that will do all that in one unit. They will also cut the Utility AC if it doesn't sense power. Also come with up to 900V Max PV Input Voltage. They do exist, yes they are harder to find but they exist.
I have a charge controller I came up with just because of that. It's 200amps continuous 500 amp surge. 12-24 it's just under $200. 48v a little more. I am setting up my solar system just that same way. A few small differences but mostly the same. Thanks for a great video
Great job explaining, and thank you too, because I have been looking into adding batteries to my grid solar system. I will check out all your videos and go to the Facebook site you have; Professor!
Wonderful video !! Only thing that Threw a huge red flag was all those batteries sitting on the bare concrete floor ! There are plenty reasons this stuck out like a sore thumb, shucks even if you did the minimal like setting them on 2x4's they would last ALOT longer .... I am NOT being critical of your well thought out project , Its amazing and one day i hope to be able to afford doing something of this magnitude. Well Done Bro !!
One other question that I have. Do most grid tied systems connect to the house breaker panel before the main breaker or after it? I remember the installer saying that they had to do a hot tap and I was wondering why they didn’t just turn off the main breaker to do the connection. That’s the reason for my question because if the solar connects before the main breaker, I would have to split off the incoming solar and connect to my panel with some type of manual switch.
Awesome videos! Man, I want your knowledege. I'm having a house built and it will be finished on 1 Dec. When is the best time to installed the panels of I'm having a comlany installed them on the roof? The reason I'm asking is due to the wiring inside the house...inverter connected to the house elec panel. Thanks for your videos!
You can prepare the whole thing But remember in Winther All thing shrinks So when you tighten the PV fasteners Use a moment / torq wrench And tighten again in summer... Ther can also be problems with Tighten kit.. when ITs too Cold IT won't .. dry Up and make thing wather tight
I love these dubs. It's sounds a little bit schizophrenic, like 'smarter you' is interrupting 'dumber you'. Not that 'dumber you' isn't smarter than me already :) It could be edited to be a bit smoother but it kept me entertained as well as informed. Good video series. :)
Cool set up I’m just finishing up a 30 kw inverter system 300v aims charge controller 5 solar arrays 680 volts per array 25 batteries in series 300 volts 100 amp hours for off grid system
Do you have the Conext XW6648's "AC In" connected to grid power through another breaker (separate from the interlocked backfeed), so that it can maintain charge on your batteries during normal grid-up conditions? Also, you might want to consider moving battery cables so that + and - lines from the inverter connect to diagonally-opposite points, to better equalize load across the three parallel strings. Otherwise, due to tiny voltage drops across the interconnect wiring (even as thick as it is), at high currents the string closer to your Conext will be worked harder than the others, while also seeing a higher charging voltage, experiencing more wear and possibly failing sooner. Nice setup, though. Compared to a standard hybrid system, AC coupling can give somewhat better efficiency when running in normal grid-tied mode, since the PV power doesn't have to go through two conversion steps, first down to 48V and then back up to 120/240 AC. The efficiency's a bit lower when running off-grid, and battery charging can be less precise, but that's not a bad trade-off considering how often you'll likely be operating in each mode. I have a traditional hybrid system with charge controllers (plus native DC loads, and other complexity), but used a similar interlock arrangement for many years until finally putting in a critical-load panel to benefit from the "whole house UPS" auto-changeover.
I do have the AC connected to maintain the batteries. I didn't include it in the video because I thought it would lead to more confusion than help. Maybe I should have. You clearly know your stuff! Good tip on the battery connections, and good point about the efficiency of the AC coupled setup. Thanks for watching!
In your diagram you don't show any isolation between your battery Bank inverter and the electrical grid. So when it starts making a sine wave, you're going to be energizing the lines going out to your pole? There has to be some kind of isolation there right
Solar Edge makes an auto-isolate inverter system that automatically switches to battery when the grid goes down. Most importantly, it also self-isolates from the grid while on battery power so there is no risk to grid repair technicians from your system. It is isolated. When the grid returns, the inverters automatically re-connect to the grid in sync with grid frequency and port excess KWH to the grid after topping off all your batteries.
Thank you for the excellent vid's on solar and battery back up. When I lose power, I pull up my lawn mower near the house and plug the battery into a cheap 12 volt 2000 watt invert er and run a 12 gauge extension cord into the house to operate a few lights and maybe the fridge if the power loss is long enough. ( isolated from the grid of course ) Your method would be way to much investment for me just to have power when the grid goes down. Also you said you have a golf cart, if it was me I would pull up the golf cart and invert the 48 volts to 2 legs of 120. ( invert er investment though ) You already have the golf cart charger, just keep it charged while you have solar coming at you. I did however learn from you that a higher voltage from the solar array is better.
How often would you have to replace your battery bank? 10 years? 20 years? Or do you just have to top it up with distilled water like the batteries we use on power lifts and cars? Or are they specially manufactured in a way that they are a burn and turn? Once dead, you replace. To discourage the average person from tampering with the batteries? They say currents as low as like say 100-200 milliamps are potentially lethal as well as any voltage over 30.
Question. New hybrid inverters have integrated charge controllers, that can use AC or DC power to charge the batteries, can can monitor battery SOC via BMS comms. Therfore, I would assume frequency shifting would not be needed, and the grid tie inverter just keeps humming to supply loads until the sun goes down, and there is no DC input. Does that sound right?
The output of the inverter is manual, but there is another circuit to power the inverter for battery management. I probably should have shown it in the video but I thought it would add confusion. So basically there is another circuit that connects the inverter for that purpose.
THANK YOU SO MUCH THIS IS EXACTLY THE INFORMATION I WAS LOOKING FOR. And you had amazing, super helpful diagrams to help a visual learner like myself understand! Your explanations are so clear!
This panel can put out close to 100 watts th-cam.com/users/postUgkxOqI2yqX0XVrhR2BMJciTWrHJpG8FhJyg when positioned in the appropriate southernly direction, tilted to the optimal angle for your latitude/date, and connected to a higher capacity device than a 500. The built in kickstand angle is a fixed at 50 degrees. Up to 20% more power can be output by selecting the actual date and latitude optimal angle.The 500 will only input 3.5A maximum at 18 volts for 63 watts. Some of the excess power from the panel can be fed into a USB battery bank, charged directly from the panel while also charging a 500. This will allow you to harvest as much as 63 + 15 = 78 watts.If this panel is used to charge a larger device, such as the power station, then its full output potential can be realized.
This is the best, most well explained, most well designed "off grid" system I have ever seen yet!
Actually this is not an "off grid" system. Not even if you use "quotes". It is a poorly designed manually controlled "AC Coupled Hybrid PV" system. Real AC Coupled Hybrid PV systems are 100% automatic.
Yep they use transfer switch ..
What a clear concise explanation.. you do a better job than many engineering professors.
Thanks for these videos, they are hugely helpful. We recently built a house in Sayulita, Mexico, and it is experiencing growing pains with frequent power outages. Located at the 20 parallel with 350 days of sunshine a year it is an ideal candidate for using solar. The power company has a monthly cap on electric consumption that when you go over the cost rate increases dramatically, and for the next 6 months. So, we are looking at all the solar options, and your series of 3 videos have helped me understand the options and issues. Thanks.
Loop moo
Dedication + Execution + Explanation + Cost Quotes + Clarity = Me Subing. Good job
Exactly. Very impressive stuff.
+1
I really enjoyed watching this series of videos and your solar setup. It is frustrating watching other channels invest tens of thousands of dollars for an off grid system when their property is capable of being grid tied all to avoid a power bill. They invested 40K++ (in parts alone) in an inferior off grid solar + generator setup to avoid paying 10K to tie into the grid. You basically validated all the points I tried to make... including investing their money in the sock market!
I really like the illustrative and descriptive information that is so easy to process, even a child can understand, like Einstien once said. If lecturers in school can start by explaining the process before the technical things.
I am very impressed with ur system and the way u are able to explain it. very often ther is the lack of logic thinking and u are gifted to do so because of studying the material.
When I got solar 6 years ago, battery systems were just too expensive and would never break even. Now though, they're just about affordable/economical and I'm looking to add one into my system too. Your video helped a lot, thanks!
Excellent explanations, especially AC v. DC coupling!
So very well and clear explained. Excellent how you correct, make yourself more understandable by editing your voiceover afterwards. It is pleasing. Everyone understands that. Thanks!
If it has issues starting heavy loads, you can put capacitors on those loads. That would help get over the initial startup draw. That would be cheaper than running two inverters.
Excellent video. Very clear and thorough. I've also come to the same conclusion as you regarding AC-coupling. In my case, I will be using microinverters as solar AC source.
According to Schneider, if your grid is out, their XW+ inverters cannot regulate the current used to charge your batteries. This applies only to AC-coupled systems. They say lead acid (like yours) can handle this 'full on' charge but other batteries like Lithium, cannot. The next time your grid is out (or as a test), see if you can measure the current being dumped on your battery bank. It should be ~140A regardless of state of charge.
It gives the amperage readout on the control panel. The amperage does vary some, between 120 and 180 or so, depending on the charge state of the battery bank. It also has a temperature sensor for the batteries that will stop or slow the charging if the batteries get too hot.
This is one main issue I see with the system in the video; AC coupled system with the "Grid-Tie" inverter (GTI) operating/configured as per Grid code can cause:
1. Tripping of the Hybrid Inverter (or both) on low load and high sun conditions (as the GTI try to output a lot more power than required by load conditions - including battery charging), or
2. overcharging of batteries; the Hybrid inverter will not be able to regulate the charging current (from the GTI) as it is not communicating with it - this can shorten battery life, if not damage the batteries - battery dependent)
Typically, in AC Coupled systems operating off-grid, where there's no direct communication between the inverters (maybe because of different brands, or simply the option is not available) the GTI inverter should be configured to operate in "Off-Grid" mode, whereby the Hybrid inverter can then "communicate" and control the output power of the GTI by varying the AC frequency (and via Frequency-Shift Power Control (FSPC) for SMA, Active Frequency Shift Power Curtailment (AFSPC) for Schneider or in this case, Power Control Option for SolarEdge); note however that the default "Off-Grid" mode may not comply with Grid code (adjusting frequency range, and adding an additional anti-islanding relay can likely solve this issue, to comply with operation with Grid present).
Otherwise, for FarmCraft 01's situation, the SolarEdge StorEdge solution could have proved easier to integrate.
I have always wanted to find out if a gridtie inverter can produced power to an inverter but today i know it, all thanks to you. Big ups and keep it up. Thank you
Hey Farmcraft, Nice work. That's a great system. However, there is an issue with your battery bank that needs correcting. You have three strings of batteries, and your main DC + and - are coming from the same string. You will balance the current between the three strings better if you have the DC + coming from string 1 and the DC - coming from string 3. As it is, you will use more current from the string on the right, and so your batteries will age at different rates.
You are right
Some batteries have more stress
Because the voltage drops on wires
Terrific but of information. Thank you.
@Paul D - Maybe the Schneider Conext inverter has built in functionality in it's charge controller though which would alleviate or minimize that problem?
Will Prowse recently did a video on that. It’s surprisingly not that simple. I don’t remember why though.
Good point but, I don't think the few millivolts drop in those cables is going to be significant.
Imbalance in the capacity of the cells is what causes failure...
A chain is as strong as the weakest link... In series cells the one with smallest capacity gets "bullied" by the others. Overcharged at the top end and depleted or even reverse charged at the bottom end.
Brilliant video. Superbly explained. This is why I love TH-cam. Not always, but occasionally a great source of information as was this case. Thanks for sharing
I would disagree on many items in this design. I do think FarmCraft101 has some great diagrams and teaching methods, but it lacks trade smarts and code compliance/safety.
There is no reason to re-invent the wheel here. I hope people don't just assume all inverters have this "multi inverter" feature, which is actually for the same models w/ proper distribution panel.
As Tofulnc says, the XW6800 hybrid could do it all.
Here are my safety/code concerns:
1.)MC cable for HVDC ... not allowed in most states! Use PVC, or EMT.
2.)16.8kW feeding into a 200Amp panel .... almost double the allowed 20% over current by code.
3.)Where is the DC combiner for 3 strings. I believe you said 1 wire for DC run.(actually 3 but need 5)
4.)Why is there a label for AC disconnect on the DC run?
5.)AC couple is not ok for just any brand inverter. Those frequency control funtions are for 2-3 same size and brand inverters with proper distribution box.
6.)Is that a suicide cord being used ... on the gen run .. and manual charge? Way not ok!
7.)Guessing that manual xfer would need a separate lockout box too ... if it was allowable.
8.)I did not see a battery breaker or other DC distribution on low volt side. Bigger bank and cable size could help start large loads using all of the 13kw startup power (maybe 10sec?) from the xw6800.
9.)Proper clearances are not maintained on XW6800
10.)No mention of grounding and reasons for it are a big missing part of safety w/ 380VDC runs in a DIY video.
11.) I have to assume that this addition is without a permit. I feel it is to the advantage for DIY to use inspectors to help make installs a bit more safe, and not void your home owners insurance.
12.)I would never recommend DIY for backup/offrid if the owner did not install the grid tie setup! It is way more complicated and dangerous!
Ok ... not to worry. I am not the inspector in your county! But this is a video to help people learn ... right? Why not show a safe more simple approach.
Here is are some things missing in your "retrofit strategy".
1.)Cheap solution is rewire array yourself for 10 of 3 panel strings of 100-150VDC.
2.)Put the proper fused DC combiner at the Array.
3.)Pull new wires if needed on DC run. How much can a DIY 300ft ditch and conduit run for a worst case scenario? Not the $1000 to $2000 extra for HV CCs. 2x 80A HVCC would get you to 8.8KW PCT or 10k DC STC if you do not want to oversize array to inverter.
4.)Bigger battery bank, proper batteries, larger inter ties/homeruns, and large xfer switch solves the startup problem. A gen along with gen load balance can also work if that compressor is really needed offgrid! Symmetrical taps would also help! Yes, high current is different than normal wiring.
5.)Realize that you do get 3300W per XWMPPT60 CC, and could go with just 2 for a 9.2karray. Yes ... you can over size an array to inverters or CCs and they just de-rate by firmware for safety when needed! It is completely allowed by the manufacturer and codes. If you want to save on equipment ... this is a place! Panels are cheap! This type of over size of 25% (9.2k x .85 PCT factor = 1.25 x 6.8k) . results in a loss of only about 5-10% depending on climate since peak power only occurs on cold days near noon time.
6.)Realize that a large manual 200A xfer switch could just be a "high power grid tie mode", and then 99% of everything else would just be automatic with the 60A XW automatic xfer. This solves your critical loads problem. Using appropriate size battery bank/ and oversized inter ties will help on motor starts. Does that large compressor really need back up ... instead of a little cheap spare? Running one or two new dedicated circuits for an item is not typically that hard. Making it look good can be hard!
7.) Have to say the already wasted money here is the original system with "optimizers".
I would guess the installer got a closeout deal ... after hearing the $1200 price for the 10k inverter .... which was originally more like $2000 plus $2000 more for the optimizers. They are just not needed on a single plane array. Most panels have "bypass diodes" that help minimize losses when a random panel fails or is dirty. Maintenance and monitoring is even a better solution.
These, and micro inverters need 4x as many weather tight plugs, which are the most likely part to fail on the array.
What a longgggg comment. It helps me stay in design shape when not installing so many systems! Maybe some one reads it ;-)
@@koisolare1266 does electricity. Also PCP.
@@koisolare1266 I read it. I'm impressed. Clearly you know a lot about it. Problem is: It is hard, very difficult to understand without schemes.
Do I understand you well? The system of FarmCraft is not safe or not as safe as it should and could be?
How much would the system cost if it was setup your way?
@@guzziventure1750 A standard XW6800 system with smaller battery bank is about 10k$ plus another 10k$ for rewire, trench and labor (PV and ground mount additional cost) A general rule for battery backup is 2 to 3x the cost of grid tie. It makes much more since to get a gas/propane backup compressor/gen if you really need that backed up. Battery backup is always questionable if you do not use it more than a week in a year.
I just decided to start with the grid tied system then ad the battery set up later. This video answered what I was looking for.. Thanks
Is this hybrid system safe for linemen? I thought one reason for grid based system was is would prevent a solar system from backfeeding the grid.
at 5:34 he starts discussing the manual grid disconnect that resolves this
@@beforebefore That's great as long as he is around to manually switch - what happens if he leaves this world and his family decides to sell. How does the new buyer deal with this setup? Not that I'm against this, just saying yes it works for him, but could be a problem for someone else since it's set up for manual operation. I have looked at property with home designed systems, some are easy to see proper operation and some are not. Would hate to hear that some lineman was killed because someone didn't have the background to properly operation a system.
@@Bigreddogs2007 The manual grid disconnect(s) makes it physically impossible (or at least impossible without modifying the panel to remove the disconnect) to feed power from the battery backup to the grid, meaning no linemen will ever be endangered by this setup. This is a common approach used all the time in generator installs (he mentions that the manual disconnect on the house predates the battery backup and was originally installed for generator use. The battery inverter, from the perspective of AC loads and the grid, is really no different than a generator, so this safety device is well suited for the task.
@@beforebefore .
tv
N .
Glad to see you used that type of batteries, lithium ion are very compact, energy efficient but are to dangerous for inside residents and cars, coming out with several new battery types like sodium ion which is approaching lithium ion but are A little heavier but much safer and can even use the same manufacturing lines, the future is a little brighter, like your videos, keep it up.
One question: When your transfer switch is off (e.g. when the grid is working), how do the batteries get charged? Maybe the "hybrid inverter" has separable AC in and AC out?
I was thinking the same thing
Yes, hybrid inverters have separate AC in and out. Some hybrid inverters have 2 AC outs one for regular load and one critical load as explained in the part 2.
Good stuff! Iappreciate the time, effort, and honesty involved. Great job.
glad he included the disadvantage of the two inverters not having a deticated control line between them but curious that he did not mention the power loss to heat from converting DC>AC>DC for charging the batteries via solar. may be minor but still significant.
Photovoltaic / Solar Thermal Technician here...
Well Done, you've even out done me, raises glass of beer in admiration.
i Like, OLE!
You do know BYPASS DIODES right..
So a Guy like Wood Seem pretty stupid
If he fell for the SERIEL PANEL'S WITH SHADDOWS WIL SHOT THE WHOLE STRING DOWN ...
YOU CAN'T SERIUSLY CALL YOU SELF THAT .. AND DONT KNOW. THIS
????
IT Will not shot down the whole string
Just bypass the shaddowed panel
Same reduktion in watt as paralell
But No freaking shut down ...
Let's her hos skat you aculey are ..
Doe's BYPASS DIODES. Bypass AFFECTED shaded areas on PANELS
True
Or
False !!!!
Hmmm got an email from Kenneth Schultz
. but his Channel doesn't have any content. I'll still answer this. but First lets read:
Kenneth Schultz to Me... You do know BYPASS DIODES right.. So a Guy like Wood Seem pretty stupid If he fell for the SERIEL PANEL'S WITH SHADDOWS WIL SHOT THE WHOLE STRING DOWN ... YOU CAN'T SERIUSLY CALL YOU SELF THAT .. AND DONT KNOW. THIS ????
Me to Kenneth Schultz... You're Correct on the Bypass Diodes. Monocrystalline panels have those, if part shading will shut off that string. Also if Light is not distributed evenly and overheating. We experimented in a classroom with Simulated Sunlight. That panel didn't want to cooperate, 2 LED lamps were being focused in the middle of the panel and Zip, Nada. Then we added more LED lamps a total of 6 that shed light evenly and Voila' panel worked more efficient. First try the panel did produce voltage but wouldn't turn on the MPPT charger.
Second try with 6 lamps it did what we intended to do. (wish I could post pictures here)
Third try, we changed panel from Monocrystalline to Polycrystalline and it worked with part shading. They both have Pros and Cons. Yes we had micro inverters then we used optimizers.
I'm not offended by your remark, why should I. it also serves as a learning tool for others where everyone benefits. I have installed some panels on RV's but I won't called myself a professional on that field. I've seen some installs that make me want to go deeper into that field.
As I stated I admired FarmCraft 101's video.
It's amazing how inverters have improved in three years. Now you can have one box to do everything. Batteries are better too.
Your videos are amazing and have helped motivate me to pursue an area of keen interest, physics Especially, since I know awesome DIY projects are so doable. You really ought to have a skillshare account, to help spread your talent for teaching. Great humor in the videos, find myself laughing a lot too.
Thank you!
Hoooooly! Fantastic Videos, THANKS for putting the time into these and sharing them!
Another negative for using a high voltage battery charge controller besides cost, that is not realized by many system designers, is the ripple current that is placed on the batteries. The Hybrid inverter DC input current draw is based on the AC sinewave load profile, meaning the current into the 48 vdc input to the Hybrid inverter is half sinewave pulses, like a full wave rectified sinewave. The 48 vdc from the high voltage PV charge controller is a more uniform DC feed with DC output voltage based on the charge state of the batteries. The batteries now act as a filter capacitor to supply the peak sinewave current and reverse DC current to momentarily push current into the battery at AC zero voltage crossings of the sinewave AC power. What this means is the batteries are subject to continuous pushing and pulling of current at 120 Hz rate which shorten their live span even though there may be no net average power draw from the batteries.
Your Hybrid battery inverter was obviously added by you after the grid tie system was installed and approved. Your installation on the Hybrid addition would not have passed inspection. At minimum I would recommend you cut a piece of plywood or drywall and cover up the exposed battery terminals to prevent accidently dropping something conductive on them. Most codes do not allow batteries to be located directly below electrical panels due to potential hydrogen outgassing by batteries, even if using sealed lead acid type.
Is there a drain cycle for the batteries in hybrid system?
Very nice system. My questions are -> 1. How do you charge the batteries when the grid is on. It seems that the Schneider inverter will be totally disconnected. 2. What happens to the Schneider when the grid is on? Do you turn it off manually?
07:05 If I am not mistaken, having two inverters will not double your energy production which is limited to the production capacity of your solar system (30 x Wp of each panel) and because only one inverter is connected to the solar system. Thus you don't need the first/old inverter, which is consuming energy.
Thanks for sharing information about your solar hybrid system.
You are not completely mistaken, but you are probably confusing energy and power. Of course the total offgrid energy is limited by the solar production, but the instantaneous power available at any one moment is limited by the inverters, let's say one driven by the panels and one driven by the batteries. So having double the watts available from the two inverters is difference between being able to use your high current devices for a short time (ovens, saws, dryer etc.) or not being able to use them at all.
@@craignels
No confusion! But one inverter can do both (I think he is equipped with sophisticated inverters) dealing with solar panels and batteries. Hybrid inverters play many roles, i.e. regulator, charger and DC/AC converter plus reinjecting the surplus of energy into the grid. Unless the intention is to secure the installation using two inverters.
@@m.bouanane4455 The intention is not to secure the installation. Rather he started with the grid tie system as a given. Then later wanted to add battery backup. He could have replaced his existing 8KW grid tie inverter with a 16KW hybrid inverter, but instead decided he would just add an 8KW hybrid inverter to his existing system. The key idea he's promoting is when adding battery to an existing system, AC coupling is the way to go.
The Sungold Power TP6048 takes the place of both the hybrid inverter and the grid tied inverter in your diagram at 1:51, right? Do you hook both the A/C input and A/C output to your system, or do you just leave the A/C in unhooked?
0:28 I have a small 300w-30V grid-tie set-up, will adding a charge controller and batteries work this way? I just want to have some more storage to kick in at night as we usually consume less power than 300w.
Very cool setup. Most real time clock chips use a crystal oscillator and would not be affected by the input frequency changing. Curious what devices you found in your house that are affected by input frequency.
You should share this video with everyone in LA and Northern California that often have solar arrays and now have the electric company turning off the grid to reduce fire risk. This would be MUCH appreciated. I will post it to many friends in Santa Rosa.
Slick. I work with commercial VFDs for motor control etc. A good surge/lightning protection system is good insurance..especially (and I don't know why) in a rural setting. They used to call them a TVSS but there is a new terminology now that escapes me.
BIG THANK YOU !!!
I am studying how to insert a [GRID-TIE-INVERTER] to my off grid solar/battery setup. (Just how you showed in your slide)
Right now im running just a circuit from my house off-grid (1 room and the fridge)
But at 9am.. Batts will be at 14volts ! So rest of the day im just throwing away the rest of the captured energy !
My setup is smaller but I guess the same rules or logic applies.
Again, thank you.
(Surviving on Solar Energy after Hurricane Maria in Puerto Rico.)
You're very welcome. I hope you found it helpful!
Please explain how to handle if production is high and load is less battery is full. i have 2kva home UPS sign wave with 2 battery. I would like to add a 3kva solar using micro inverter. Here no grid back feeding mechanism. Presently grid current is passing through my old inverter to entire house. I am not willing to throw out my old inverter for a hybrid and not much space for a big inverter so micro inverter is the only possible way.
How can I prevent over production and blowing out my old inverter in low load and high production sunny day?
I was like you, wanted a way to use my solar when the grid is not connected, My solar system is on my RV, i installed grid tied invertor system because they are far cheaper than off grid setups, plus i wanted the ability to use it when not hooked up at rv parks and boondocking. So i use an old 1500 watt invertor combined with an interlocked circuit that i plug into the system running off the RVs 12v battery system, which pumps 120v into the system and tricks the grid tied invertor to allow me to use the solar. I only have 2 batteries in my battery bank, because i invested a bunch of money into batteries 6 years back and after 4 years over half the bank was giving me issues and since they were out of warranty it was a costly expense. Now i just have 2 high quality LiFePO4 batteries and use generator power when in dire need of power when no solar is available. The load on the 1500 watt invertor is only a few watts as the grid tied invertor overtakes the system. Before someone ask why i didnt just go with an offgrid system, i spend most of my days at RV parks with electric from the grid, but they charge you a lot for electric at many places, so with the grid tied system i can supplement my electric while at rv parks with the solar system. Most RVs at parks these days have all these solar panels on their rigs and none of it is being used while plugged into the grid, just letting the solar panels collect dust. also the solar panels on my roof ended up acting as a solar barrier from heat, after i installed the panels i noticed the RV doesnt get as hot and uses far less power running the a/c system to cool the RV, because the roof isnt being heated up by the sun anymore. I have solar running the entire length of my RV with an angled deflector upfront keeping the wind from going under the panels while in transport.
You are correct that the inductive compressor motor takes a lot of juice to start up, often 4-8x the standard running amperage. But most compressors are built with unloader valves. When your compressor gets up to pressure, you will hear it shut off and you'll hear a hiss of compressed air released. This is the pressure coming off the compressor head so the motor doesn't have to work against it to start up the compressor. Interesting video.
THAT is good information to know!
You have a great system there. The only thing I can see that you might consider changing. Is the battery Bank load side wires going to the inverter should be pulled from either corner of your battery Bank. The way they're wired now it would pull from the first string where they're connected. Just move either the positive or negative to the other end. This would make it act as one big battery.
With that being said, a charge controller output would go to the opposite corners of your battery Bank. That makes the input and the output run through the batteries.
Since the 3 banks are wired in parallel why would it pull from the first series string instead of all of them equally?
@16:28 The load side conductors are on the same string. Although their in parallel, it will pull from the closest set first. So, your first string will take most of the load. I would pull from either end for your load and the opposite terminales for you line in. This will act as one big battery this way. the line in has to run all the way to the other end for the load. (not being a smart ass) Think about it. It makes sense. Hope this helps. I'll try to find some links to help out. Your not wrong but I think that it might cause extra strain on that first set.
Agreed, because if the voltage can only come from one, it will, essentially.
Drunkinone can you share a drawing, thanks
This seems to be ingenious way to add batteries to your system!!!
Hi Farmcraft
I have the solargain as well and I actually bought a seperate solar panels through Ebay with seperate charge controller and using lithium battery 48 volts which supply all my garage needs using 8kw inverter and essential home needs if grid drop down
Good video on AC-Coupled Solar setup. However if you know you would like to have battery backup as a requirement for the power system for the farm or house, It would be more economical for you to consider the solar PV systems from OutBack power. The one inverter / generator charger does it all in one unit. The whole system only has 3 major components the panels, the battery charge controller and the inverter. If you generate more power then you use, it will push it back to the grid, IF the power grid fails the inverter will power the house, off the batteries . In the event of low batteries, it will turn on a backup generator to charge and power the house.
Thanks for the info!!!
@10:00 - could the batteries be oriented so that each negative pole connects to the neighbor's positive with just a short busbar?
Yes, that would work fine. Careful if the busbar is not insulated. Even with my insulated wires I'm careful not to drop anything metal on them. Could be an exciting short circuit.
One thing that I would like to see you do is to put those batteries on a shelf system so you can get them off your floor. The risk of something or someone falling on them is there, and a wall mounted system would be safer. The way you did the battery control with those inverters is good, and I would do exactly the same if I was in your situation. Spending more money on extra solar controllers is really no point when those inverters does the same job for less money. Great system without using tons of money.
I live in a small....
Crap i forgot the word for the house with multiple floors we learned it literally on the first english lesson....
house thing on a dense city area. I have a balcony, but too small to put just about any solar panels on. And the grid is just about never down. Or more accurately it's down a few times every summer, but gets fixed usually within half an hour.
So. The point is. I have no practical need or the possibility to use anything i learn from this video. Or the other solarpowervideos i did watch the parts 1&2 and plan on watching that invest thing video too.
I enjoy this. For no reason other than learning practical but unpractical things. And you never know i might move somewhere someday where i'll have the need for this.
So if your battery inverter never see line power how do you make sure the battery are changed when the power goes down because you turn the grid off to turn on your battery
Transfer switch .. either the generator kicks ind or battery
Goe's until power is to low Then generator KICK's ind
Chardged BATTERY run hous until power comes back
I like the idea of a critical load panel you mentioned at the end of the video! Makes a switch over simple.
I have a grid tied system with an emergency power generator that has a whole house ATS service rated transfer switch to operate everything when the grid is down. And was considering adding a battery bank connected to a separate inverter like you did.
You can modify shop machines to work with low starting current. An unloader solenoid valve on an air compressor will dump the pressure at the outlet, and it will start easily. This is also possible with air conditioning but is more complex because you can't release the system pressure to the atmosphere.
Your explanation of the two Banks communicating via frequency, I can put a meter on my outlets right now and they will fluctuate from 55 to 64 HZ depending on what the atmospheric conditions are outside. I've even measured it going down to 51 Hertz during a thunderstorm. So how does the brainbox no what is a communication and what is a natural fluctuation of frequency on the power grid?
well explained...I do have some Qs for you.
First I have an existing grid tied Sunny Boy solar system of 2 strings of panels totaling approx.12kw.
I have a 48vdc 15kw 120/240 split phase pure sine-wave inverter/charger with no MPPT solar charger with 640ah battery string.
The inverter manual say's
The 15000 watt inverter features Dry Contacts Providing Frequency Switch Between 60Hz / 62.5Hz as the secondary charge control of on grid inverter.
It can control excess energy from the grid tie inverter when the battery bank reaches a voltage within the manufacturer’s limit.
To accomplish this, you can use a voltage-controlled relay to close the dry contact to switch the output freq from 60hz to 62.5Hz, shutting off the grid tie inverter system temporarily.
The paragraph end there with no explanation as to what I can do with that temporary shut off
I want to set up the A/C coupled system, I am not sure what I need at this point.
Do you have some suggestion or maybe a good source in which I can better educate myself in this area...any help is greatly appreciated.
Thanks for this series on your solar power setup. Im trying to educate myself and this was very informative and easy to understand. Again, thanks!
The way you are doing it is nice. I would suspect also that your batteries will last longer since they are not cycling everyday.
I was thinking using overlapping systems. One completely off grid powering certain circuits in the house such as all lights and some power circuits full time but with a 3 way changeover switch through a sub board. Possibly using a victron inverter charger..
HI. Great system. Have you changed the battery connection on either the Pos OR Neg yet ? Eg: Pos on Row 1 Pos Terminal Neg on Row 3 Neg Terminal . This will increase the life of your battery system. The load will be balanced. The amps from each row will be the same. At the moment, (as shown in the video) Row 1 will provide more amps than Row 2 and row 3 will have the lease amp draw. Batteries will deteriorate at different rates. . . . . Simple fix. . . . Move one cable only..... Good luck....
Thanks. Yeah, I did that some time back. Cheers.
Hi Farmcraft101.
Just seen this good video of yours for Ac Coupling to add battery storage to an existing solar Pv system. The system video is great and well explained. There is however one thing I have noticed as you were showing the way your batteries are interconnected in the battery bank:
I notice that the battery bank negative and positive cables leading to inverter, are terminating on the “same side(edge)” of the battery bank, which is not supposed to be the case when you have more than one string of batteries connected in parallel in a battery bank. The two cables (positive and negative) leading to the inverter must terminate at opposite ends of the battery bank. This ensures that each string of the eight batteries passes equal current during charging and discharge. (I don’t know what I’m explaining going to come out clearly without a diagram to illustrate, but I hope you grasp what I mean).
In the current configuration you have, the back string (closer to the inverter), passes more current than the middle string, and the middle string passes more than the front string (near the where you are standing in the video). So, front string has lowest current, middle string has medium current and back string has the highest current. The reason is as follows; the back string has shorter path and thus lower electrical resistance; the front string has the longest path and thus higher electrical resistance; the middle string electrical resistance is higher than back string and lower than front string,
The magnitude of currents drawn from and fed to battery banks by inverters are very large and therefore very small differences in resistance in the electrical path passing these large currents have a very large effect on battery chemistry as time passes.
Initially, since all the individual batteries are freshly installed, you will not notice any effect, but aa time passes and days turn to weeks to months, your battery bank will start aging unevenly with some batteries aging faster than others. That may surprise you, but the reason is; the uneven(unbalanced) currents passing through the three strings over time.
In short, the string passing higher currents than another ends up being cycled more than the other, and battery age is all about cycles.
If there was a way to attach an illustration diagram, I would have given you a diagram to explain the recommended method of connecting the two end cables to a battery bank with more than one parallel strings.
I think the distance of extra cabling from each parallel battery string is probably negligible, considering how close the battery strings are (right next to each other), and also the gauge of those terminal wires (very thick, minimal resistance). Thus the difference in path resistance for each string is probably quite negligible for this case, in my opinion.
NICE! I have a 7.8kW grid tie solar system. I was wondering how to get the solar power to be usable during outages. I did not go to the 'solar wall' when I put the system in three years ago as it didn't seem financially sound at the time. My solar has made my electric bill $19 / Mo except for Feb/Mar/Apr. The house is currently 'all electric' as built. As I replace resistance heating with propane, that will change. I am now putting in a 25kW diesel genny in my shop and it will be hooked to all buildings on the farm. I am going to build in auto transfer to control the switching over during outages. This system will provide backup to two separately fed, two utility meters, so it will require two ATS systems, easy enough to do. I am still going to, experimentally, look into a battery system like yours. With the auto transfer system I am building, tying that in would be easy. I always wanted to do a wind turbine, but they are being put in the shadows by PV. Way too much maintenance required for the benefit at this time. Thanks for the excellent video, and thanks for sharing the knowledge and experience. The technology changes as we speak... Now Subscribed.. Michael in CO. I should have read some of the comments before I commented... You just have to ignore some of the breathlessly uninformed when they fire up their armchairs. Whew!
Nice one. How many Kwh do your Solar PV produce per year
I watched all three videos in this series and I found it very informative and it answered several questions I had while looking into PV cell installations and as such I gave you a thumb's up on each :)
The battery backed-up system is "obviously" the preferred technical solution, but I'd say that it would bump up the overall price of your installation by several thousands of dollars, thus extending the period over which you would break even on your investment. Also, you failed to mention that each "component" of your installation (the inverter, battery charge monitor, panels, etc) has a limited lifespan. At best each device will slowly degrade in efficiency by a few percent per year, meaning there will be losses in power transfer (some of the produced power will be lost as heat, or batteries will be charged less). Worst case one or more components of your installation will simply "catastrophically" fail and will probably need replacing rather than repair.
Safety wise I would not count on a 8.5 years break even period but rather a 10 to 11 year break even period just in case one or more components will EOL on you prematurely. In other words you're looking at a much steeper investment initially (or within the projected break even period of 8.5 years). If you intend to keep on living in your home for longer than 10 years after installation of your solar system, however, having a solar panel system (even with battery backup) still makes sense, notwithstanding possible degradation issues
We also went through this calculation when considering our setup (and decided against battery backup), you need to add in interest, ie if you invested the money instead of buying the extra equipment there would have been a return, and, over 10 years that may be quite large.
Sorry, I forgot to add... a great video and very informative. Thank you.
THANKS MAN !!! watched all 3 solar videos...great work.....i like the set up !!!
7:25 You talk about starting your 5HP compressor. I need some advice. I have a 4kW hybrid inverter which blew up while using my 3500W shower heater when the sun was down and we were on grid power. The inverter is set to shut down when the sun goes down so it can save the batteries for when we have our frequent blackouts. I'm just the consumer. I know very little. My installer is taking no responsibility and neither is the manufacturer. My question is: Do I spend $1400 to replace the main board in the inverter or should I buy a better inverter?
System: 18 x 280W Maharlika PV panels
Must PV3500 Inverter 4KW~12KW
8 x 12V 200AH 19.2kW Battery Storage System
If the inverter is under warranty I think it should be replaced for free. What are they telling you is the reason for failure? You really shouldn't be able to "blow up" an inverter. I don't know anything about that brand, but if you try to draw more than the inverter can put out it should automatically shut down, protecting itself from overload. If the battery voltage drops too low, it should also shut down. Either it was installed correctly and then the manufacturer should cover their inverter, or it was installed incorrectly then the installer should fix it. But I guess if it was installed correctly, and the manufacturer is not covering their product, I would say get a different inverter. They aren't cheap, but the Schneider Conext inverters are nice and they stand behind them.
FarmCraft101 , thank you for the response. They say the main board blew because too much draw from the house, mostly the instahot water heater, which they say could have spiked at over 4 times the rated 3500W draw.
That shouldn't hurt a properly designed inverter. Sure, maybe you were trying to draw too much current, but the designers should account for that possibility and put in overload protection. I mean, what if you had an appliance go bad and short out. That's a straight connection from hot to ground, and will pull massive amps briefly. My generator has a breaker for that purpose as well.
You've confirmed my own thoughts. We have a generator also, a Honda 2500W, and we've overloaded it several times. The breaker flips and no damage done. I opened the front panel, thereby cementing my decision not to repair this inverter, and a gecko was in there smiling at me. I did not see a fried gecko in there, but I couldn't see everywhere either. Definitely a possibility.
As much as I would like a Schneider Cenext inverter, I'd need the 5.5kW and it's way out of my price league. Not to mention, the shipping to the Philippines would be over $1000. I haven't decided yet which inverter I will go with. Thank you again for your help.
I have been trying to figure this out for years. Thanks!!!!!!
This dude does a good job of analytically explaining his system
You are a great teacher if I was able to (mostly) follow all three of these videos thus far. My question for you is are you still able to “sell” extra power to the grid when you retrofitted the batteries to a grid tied system. I watched this twice and did not find the answer to be yes. That doesn’t mean I’m right, and I’m hoping I’m wrong and you just didn’t address this option during this video. I know this is a few years old so I hope you are still responding to comments. The tax credit drops this year from 26% down to 22% next year so I’m hoping to figure out if it’s smarter to start with the less expensive option now to get the better tax deduction this year, and as I have more money in the future add on like you did. Thanks for all your great videos and sharing your vast knowledge !
A very good video. We have 20 panels and a maximum of 5 KW out put but we get at peak times about 4.5 KW of power with no batteries yet and on the grid. We do have an an advantage we live in a very sunny and warm climate. It has been only 4 days since the install and after a few years consider a second system for providing energy at night and powering the grid. That would mean an extra 10 panels and Thailand has stated that they will have a buy back system in place this year. Depending on what they offer I will think about adding panels. However we are almost paying nothing now as I have taken meter readings every day and if after 30 days the power is = then we should pay 90% less the next month for the PEA electric bills.
very good explanation (so far the best i've come across) but what you did not mention is that, without a transfer switch (or killing the mains breaker) power will flow from you PV system to the transformer on your power pole and then try to produce 7200v into the grid (transformers are bi-directional) this can kill a lineman working on the transmission lines and it will burn out your batteries or generator which will give it there all trying to produce the tremendous load called for by the transformer. that is why you never connect a generator or batteries to your panel without an air gap to the transformer on the pole outside your house.
This helped me too. I have a 30-panel system and I was contemplating a battery back up. Thanks for the info.
Great explanation of the different systems and how they operate and the different components within the systems and all the rest. I have been trying to learn all this stuff for a while now and you sir just explained all my questions in one go Bravo! and thanks.
Man owning system like this for my home is my dream.
Nice system. Just a few month ago I was in a similar place as you. I ended up going with a solar charge controller because my gridtie DC voltage lined up with the battery bank and I wanted the inverter to keep running in the night.
Hello. your video is very interesting. I would like to know if it is possible to use a pure sine wave converter 12v 220-240v instead of a hybrid inverter. thank you very much.
The system needs a load or you will fry the off grid inverter. In. This case the batteries are the load.
Another option that is also AC-coupled, is a Victron Multiplus or Quattro inverter. You can put the SolarEdge inverter on the output of the Multiplus. It works the same way, charging the battery from the AC output of the PV-inverter, but you have the advantage of an automatic changeover. The grid is connected to the input of the Multi, and if the grid fails the Multi disconnects it automatically and powers the output, allowing the PV-inverter to continue working. It also supports a feature called ESS (Energy Storage System) that can in some cases control the PV-inverter (doesn't work with SolarEdge, SE doesn't support SunSpec model 123 in their implementation, but does work with Fronius) even while tied to the grid (ie when frequency shifting is not possible).
Exactly like I would do it
Wow! There are some genuine experts in the chat! Do you guys make any content?
@@davebutler3905 I don't generally tell people this, but I actually work for one of the companies in question... which helps 🙂
A midnite solar 250 charge controller will give you enough to run your whole array, one per 10 panels and eliminate the gridtied inverter. You would not have to manually manage your system. Lithium batteries are also awsome over lead acid, I made the move and loved them, no more smelly sulfur and watering, they also maintain a constant current under load unlike lead acid .
Rebelto Harrigan jr thanks for sharing. What type of lithium batteries are you using? Manufacturer?
separate question... WHAT about Grounding... Array, and all the rest... can you do a video on that? Is it necessary to have or no?
so it's not just fuel and power we pay way more for here in Australia, it seems batteries and inverters are in the same boat also.
Mow Money Mods Perhaps start manufacturing them instead of sending all mined stuff to the manufacturers :)
The most efficient way to get 220V or 110V ac should be to configure the panels to a high enough voltage so that when alternated with the most simple electronic circuit possible (transistor array on a signal generator) the result is the voltage you are trying to achieve. Obviously you want a bit extra for the times the sun is slightly overcast or not perfectly aligned. But basically this is why all grid tie inverters only start working around 110 - 150V DC and can often work up to around 400V DC. There should be an optimum voltage so it is good to aim for this voltage when building the array. Noting that you are limited by any panels that may be working at lower power levels when wiring in series (due to damage, smaller panel size or unbalanced strings).
One thing i would like to say is that for most people they are better off using "thin film" panels (if they have the space and money), other wise solar tracking or a longitude near to the equator and a guarantee of many full sun days throughout the year are necessary to really benefit from mono and poly crystalline panels. Thin film are also great when partial shading might come into play due to unideal installation limitations.
Great explanation but I'm still slightly confused on one point. If the grid is on, how does the battery inverter get power to keep the battery charged? I understand when the grid is down, the inverters are connected through the panel and the interlock.
Perhaps do you manually cut the power occasionally to test your system and top off the batteries?
Never Mind, found answer lower in the comments. Thanks again
Clear as mud to me. I have a lot to learn.
The only component I know is the battery 🔋
really good. You get to keep your grid tied system.
Where did you find the settings to make the solar edge inverter curtail @FarmCraft101?
Thanks for your vides and detailed explainations. They helped me better understand the various system configurations (and complexities). You could definitely have (and maybe do by now), an automated transfer switch (to switch to battery bank when the power goes out). Your power probably doesn't go out much there. But around here the power is shut off every time the wind blows (over maybe 23mph or something?) due to wildfire risk.
We went through one. 1500 of my neighbors lost their homes. But being without power for what has been in rare cases 5 days at a time (and 6 weeks during the wildfire), has been an inconvenience to say the least. The power has gone out here almost every week at least one day (and sometimes several), as they are currently [finally] upgrading (and replacing) the distribution infrastructure, and have to shut off the power to do so.
I'm currently trying to build a system (on a very limited budget and with limited knowledge of Solar Systems or electrical in general). It is difficult to say the least, and will most likely be off grid (even though Grid tie systems now are more technologically sophisticated/ capable). I don't really have the finances to hire an electrician and do everything to code/ get inspections, etc. (of course it still has to be safe and not backfeed, etc.). I bought a hybrid inverter and 30KW/h LifePO4 battery bank (still sitting unused) at this point.
Very Interesting... just wondering a couple things that aren't clear.
Where does the power go when it's a clear cool sunny day (=high watts!) and the batteries are fully charged, and there are no loads in the home?
I'm pretty sure the 'frequency curtailment' or frequency shifting as it's sometimes called, is outside of the string inverters intended design limits, and voids most string inverter warranties.
14:21... Ok... question! How batteries are more easily/faster being charged? Through AC voltage from a smart off grid inverter, or through DC voltage from a charge controller?
If anyone knows...i would appreciate an answer!! Thanks!
You can get Hybrid inverters that will do all that in one unit. They will also cut the Utility AC if it doesn't sense power. Also come with up to 900V Max PV Input Voltage.
They do exist, yes they are harder to find but they exist.
I have a charge controller I came up with just because of that. It's 200amps continuous 500 amp surge. 12-24 it's just under $200. 48v a little more. I am setting up my solar system just that same way. A few small differences but mostly the same. Thanks for a great video
Great job explaining, and thank you too, because I have been looking into adding batteries to my grid solar system. I will check out all your videos and go to the Facebook site you have; Professor!
Wonderful video !! Only thing that Threw a huge red flag was all those batteries sitting on the bare concrete floor ! There are plenty reasons this stuck out like a sore thumb, shucks even if you did the minimal like setting them on 2x4's they would last ALOT longer .... I am NOT being critical of your well thought out project , Its amazing and one day i hope to be able to afford doing something of this magnitude. Well Done Bro !!
th-cam.com/video/3cH-AL2rkpY/w-d-xo.html
Very helpful video, but can you do this with APSystems QS1 micro-inverters? So far, I have NO grid down power, nor any way to get there.
Very Smart. Learn a lots. very complicate information. Do you have a Website to teach in detail
One other question that I have. Do most grid tied systems connect to the house breaker panel before the main breaker or after it? I remember the installer saying that they had to do a hot tap and I was wondering why they didn’t just turn off the main breaker to do the connection. That’s the reason for my question because if the solar connects before the main breaker, I would have to split off the incoming solar and connect to my panel with some type of manual switch.
Awesome videos! Man, I want your knowledege. I'm having a house built and it will be finished on 1 Dec. When is the best time to installed the panels of I'm having a comlany installed them on the roof? The reason I'm asking is due to the wiring inside the house...inverter connected to the house elec panel. Thanks for your videos!
You can prepare the whole thing
But remember in Winther All thing shrinks
So when you tighten the PV fasteners
Use a moment / torq wrench
And tighten again in summer... Ther can also be problems with
Tighten kit.. when ITs too Cold IT won't .. dry Up and make thing wather tight
I love these dubs. It's sounds a little bit schizophrenic, like 'smarter you' is interrupting 'dumber you'. Not that 'dumber you' isn't smarter than me already :) It could be edited to be a bit smoother but it kept me entertained as well as informed. Good video series. :)
Cool set up I’m just finishing up a 30 kw inverter system 300v aims charge controller 5 solar arrays 680 volts per array 25 batteries in series 300 volts 100 amp hours for off grid system
Do you have the Conext XW6648's "AC In" connected to grid power through another breaker (separate from the interlocked backfeed), so that it can maintain charge on your batteries during normal grid-up conditions?
Also, you might want to consider moving battery cables so that + and - lines from the inverter connect to diagonally-opposite points, to better equalize load across the three parallel strings. Otherwise, due to tiny voltage drops across the interconnect wiring (even as thick as it is), at high currents the string closer to your Conext will be worked harder than the others, while also seeing a higher charging voltage, experiencing more wear and possibly failing sooner.
Nice setup, though. Compared to a standard hybrid system, AC coupling can give somewhat better efficiency when running in normal grid-tied mode, since the PV power doesn't have to go through two conversion steps, first down to 48V and then back up to 120/240 AC. The efficiency's a bit lower when running off-grid, and battery charging can be less precise, but that's not a bad trade-off considering how often you'll likely be operating in each mode.
I have a traditional hybrid system with charge controllers (plus native DC loads, and other complexity), but used a similar interlock arrangement for many years until finally putting in a critical-load panel to benefit from the "whole house UPS" auto-changeover.
I do have the AC connected to maintain the batteries. I didn't include it in the video because I thought it would lead to more confusion than help. Maybe I should have. You clearly know your stuff! Good tip on the battery connections, and good point about the efficiency of the AC coupled setup. Thanks for watching!
In your diagram you don't show any isolation between your battery Bank inverter and the electrical grid. So when it starts making a sine wave, you're going to be energizing the lines going out to your pole? There has to be some kind of isolation there right
Solar Edge makes an auto-isolate inverter system that automatically switches to battery when the grid goes down. Most importantly, it also self-isolates from the grid while on battery power so there is no risk to grid repair technicians from your system. It is isolated. When the grid returns, the inverters automatically re-connect to the grid in sync with grid frequency and port excess KWH to the grid after topping off all your batteries.
Do you know what model inverter system this is that you refer to?
Thank you for the excellent vid's on solar and battery back up. When I lose power, I pull up my lawn mower near the house and plug the battery into a cheap 12 volt 2000 watt invert er and run a 12 gauge extension cord into the house to operate a few lights and maybe the fridge if the power loss is long enough. ( isolated from the grid of course ) Your method would be way to much investment for me just to have power when the grid goes down. Also you said you have a golf cart, if it was me I would pull up the golf cart and invert the 48 volts to 2 legs of 120. ( invert er investment though ) You already have the golf cart charger, just keep it charged while you have solar coming at you.
I did however learn from you that a higher voltage from the solar array is better.
How often would you have to replace your battery bank? 10 years? 20 years? Or do you just have to top it up with distilled water like the batteries we use on power lifts and cars? Or are they specially manufactured in a way that they are a burn and turn? Once dead, you replace. To discourage the average person from tampering with the batteries? They say currents as low as like say 100-200 milliamps are potentially lethal as well as any voltage over 30.
Question. New hybrid inverters have integrated charge controllers, that can use AC or DC power to charge the batteries, can can monitor battery SOC via BMS comms. Therfore, I would assume frequency shifting would not be needed, and the grid tie inverter just keeps humming to supply loads until the sun goes down, and there is no DC input. Does that sound right?
If your hybrid inverter is only hooked up when the grid is manually disconnected, how do you keep the batteries charged when the grid power is ON?
The output of the inverter is manual, but there is another circuit to power the inverter for battery management. I probably should have shown it in the video but I thought it would add confusion. So basically there is another circuit that connects the inverter for that purpose.
Nice video. One question why not go completely off grid ? Use your battery system to run off of ? Have a back up generator instead ?