Charging a 48V battery with only two solar panels in series? Here are my concerns.

I'm doing some more (and final) testing with the Hyundai Shingled Solar Panels. I have connected them the same way as they will be installed on the roof in 2 week's time. My biggest concern is, having only two panels in series to charge the 48V battery. As it will be fine under sunny conditions, what happens though with shading? Will the voltage still be high enough to push more electrons through the battery?
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[@denniskenny72]

I'm glad I'm not the only one that stresses about these type of decisions . EMP & lightening protection is my latest "umm" moment love to see you battle that one mate. As always great systematic approach Andy

[@OffGridGarageAustralia]

Thanks Dennis, I'll discuss this with the electrician next week. The SPDs are still not connected, and I want to know about all this as well.

[@keyem4504]

This system is a huge overkill for powering just the garage. I love it. 🤗

[@wideawaketotruth5301]

A man's got to do, what a man's got to do. Cheer's.

[@MNGermann]

The goal is 1.21 gigawatts Marty. :P

[@76queen]

More power will charge the car a lot faster!

[@JayDee25895]

This is going to get better and better from here, so glad I'm a Subscriber 😉

[@OffGridGarageAustralia]

Thanks a lot. It's huge experiment.

[@krg038]

I have similar panels @45v 9a. Rather than using panels in series to charge the 48v I use boost converter on each panel and use them in parallel to the solar charge controller. Whatever you need for the charge controller just boost the voltage. Series panels are hurt by one panel shaded.

[@evil17]

I have considered this idea myself, what sort/type/wattage boost converters are you using for this & are they weather proof? Also, do you run extra wires for this setup, ie; how many panels with boosters do you run on a single wire to the controller? This idea does have some great potential pro’s

[@krg038]

@@evil17 my panels are 400w45v @9a on a east-west moving tracker. I have 8 rows 4 panels. So. Cal usa. Each row has a joiner box with 4 600w boost converters (probably over kill) feeding into a wifi solar controller. Not victron. 8awg solar wire. Feed the panel input to a converter. Adjust converter outputs 54v to a solar controller parallel to the bms. 5-48v battery. Jkbms.. converters and solar controllers for each row in a large plastic box with fans/ filter on the bottom. Water tight output hole for cables. Relatively low cost. Lots of solar wire for parallel mode. Fused each panel. 1 solar controller per 2 panels (for cost).

[@ToddLarsen]

Shaded Off Grid Garage lol I'm glad I don't have to deal with plants shading my array, that being said I'd love it everywhere else. Thanks for sharing and as always keep building 👍

[@OffGridGarageAustralia]

Sometimes, I am! 😎

[@extremeacc101]

I hope these uploads are scheduled mate. Otherwise, you are one crazy machine. Stay charged. Thank you Andy for your excellent content.

[@glennp2288]

Very exciting. Can't wait to see it up and running.

[@OffGridGarageAustralia]

Yeah, me neither. It will be a lot... of power. But this huge upgrade is more for wintertime. Summertime is never a problem.

[@TheRonskiman]

It's all happening much quicker than I thought it would, in the UK it's getting very hard to get hold of anything solar related. Getting quotes for installs is getting very difficult, and very expensive. I'm very interested to see your new panels go up.

[@clarencewiles963]

I think you’re shade is about what I have. As of now I don’t have anything Solar. Im beginning my journey. As you have pointed out it’s more about input. Thanks.

[@blackswansystem]

Another awesome video, thanks Andy. Also can’t wait for a Powerwall v3 update.

[@OffGridGarageAustralia]

All parts are on the way now. I'll do the solar upgrade first and then we can concentrate on the new battery/powerwall setup again.

[@chuxxsss]

Morning Andy, calm before the storm down here. Hope you son is safe, was watching Echuca and the towns sandbaging work, real champion effort.

[@OffGridGarageAustralia]

Not sure where he lives actually but he's still on his way... it's a long story...

[@gumpster6]

I enjoyed the shading tests. Good to see your concern is nothing to worry about.

[@texciler]

I also have two roofs in a 2p2s configuration with similar voltages per panel/module and a 48V battery. In real life it is working much better than I expected. As you saw in your palm tree test (which seems a more realistic shading situation ;-)) diffuse light is often enough to get reasonable string power. I am pretty sure: It will be good!

[@OffGridGarageAustralia]

Thanks a lot for sharing your experience. Good to know.

[@reboservices5165]

Chain saw

[@Revnge7Fold]

@14:42, man that was so funny! Andy you are the best!

[@taulli1]

No, not stupid at all. Fascinating, to know how the series string is effected by shading!

[@taulli1]

I am probably as excited as you are to see these new panels arrive.

[@AusMarineRobotics]

Another great video Andy - interesting to see how much a little natural shading can impact the output even when the voltage is maintained. Seems like about 15% of shading produces a 50% current drop? Have you ever done a comparison of different panel types and the impact of shading? I think your palm fronds are great for simulation - maybe a useful unit to calculate the impact of shading!

[@OffGridGarageAustralia]

It's very hard to compare. I have these panels on my driveway for a long time and watch them all day long (literally). They are pretty much in the same location and still the outcome is different as shade is never the same even if the panels are that close together.

[@junkerzn7312]

Well, it depends what the voltage specs of the MPPT are. There is no reason why a single panel < 48V wouldn't be able to charge a 48VDC battery system. To do so, the MPPT would have to be a buck-boost (able to boost a lower voltage higher or buck a higher voltage down). In terms of the current going down when it shouldn't... that could be a function of the MPPT controller. Check the "operating" input voltage range for the MPPT controller against the maximum power point of a single solar panel. Another possible issue (even likely issue) is that the MPPT controller is confused... because one panel is shaded, the power curve is actually not a uniform curve. It probably has two peaks and the MPPT controller might be stuck on the wrong one. There might be a setting in the charge controller for this, in fact. For example, my SMA inverter has an interval setting where every minute or two it does a quick sweep with the MPPT to make sure that it is actually on the highest peak (when the curve has multiple peaks due to shading, this is important). Try connecting only a single panel to the same MPPT controller (remove the 'shaded' panel from the series entirely). If this works properly, connect the second (shaded) panel up and see if you can connect up a resistive load and get 9-10A out of it, and calculate the power. i.e. determine if the charge controller is to blame or if the second panel is not bypassing properly and that is to blame. -- When bypass is working properly, the loss in power should be exactly one panel's worth of power plus an additional diode drop's loss of power (typically 0.3V to 2.1V or another 0.5% to 4% or so) due to the losses through the bypass diode(s).

[@gf-xy2of]

Victron SmartSolar MPPT 150 (for example) datasheet sais that it requires a minimum PV voltage of Vbatt+5V to start, and Vbatt+1V thereafter (so it is obviously not a buck-boost). It does of course search the global MPP, but if the global MPP of the shaded PV string combination happens to be below Vbatt+1V, then it can't be used, but only the next best MPP >= Vbatt+1V can be selected by the controller. I can't asses whether this was happening here, but I would not rule it out. I also tend to be not a friend of parallel connected strings if they are subject to different amount of shading, since differently shaded strings with bypass diodes have different MPP voltages. I'd rather prefer one string per MPPT controller, and I also prefer higher string voltages (i.e. more panels in series). As you say, within a single string, shaded panels (or even shaded sub-regions of panels) are excluded properly by bypass diodes, with only small losses. Limit for the max. number of shaded panels in a string is again the lowest PV voltage supported by the charge controller.

[@edwardvanhazendonk]

Don't freak out, it will work! That will be some nice currents charging your cells. Please take some precautions for packs which are full and the load on other packs (however it is DC, so current should also taper off)

[@deanmcbride8747]

You're videos are great fun to watch. I'm thinking of buying a victron easy solar ll gx. If I need help I might be in touch setting it up. Dean 🇬🇧 🙏 ❤️ 🙏

[@OffGridGarageAustralia]

The Easy Solar is a great device, you can't go wrong with that.

[@bexraphaela]

This is really cool. I’m trying to power my boat with solar panels

[@egnegn123]

Great test, Andy! But I question the use of shingled panels without any bypass diodes in your specific setup with shading. As you have seen, when covering one shingled panel of the series setup completely the production drops to near nothing. Of course, this no realistic situation, but if the any of the panels is in shadow only 50 % the complete string will not provide more than 50 %. So the weakest panel defines the output of the complete String. On the other side 2 halfcell panels with 3 bypass diodes in similar setup will have 6 bypassed sections. You can have even more sections if you put 3 panels in series. So in shadow situations the bypass diodes can bypass the weaker sections and you get higher current and higher power. If you use the shingled panels than you should put them in a orientation where section after section is shaded by the moving sun. Of course, in such complex situations we don't know the result in advance. So the discussion is kind of academic. With your total of about 13 kWp, you have plenty of power for the most part of the year.

[@fldutch]

Well the test aint that stupid and teaches me a lot for my setup. But i'll try a retest for the situation in my office anyway - because i have to chose wether to go for a serial or parallel string setup because of partial shading with the sun sneaking around the corner of a building. Thx for the vido.

[@OffGridGarageAustralia]

Ah, right, yeah, that is such a situation where you could have a hard shadow one panel and the other one is in full sun. It's a difficult decision as if a series or parallel connect is better. It all depends on the shadow and time frame and ability of your MPPTs.

[@bassobalalaikka5005]

8:45 Andy you are one shady character :-) with love from autumn Finland

[@OffGridGarageAustralia]

Hahaha, yes, I had to try if I can do it 😂

[@jasondevine6014]

Yes the maths of mppt doesn't lie no matter the newest cell technology. Your other option that might be a good one is micro inverters o. Each panel. This would be the best for highly shared areas like yours.

[@OffGridGarageAustralia]

Micro inverters are great when you are grid connected but very tricky in off-grid systems. If the battery is full you need to tell them to stop producing. The Victron MP II can do that but only for a limited amount of load (Victron 1:1 rule). That would not be enough in an off-grid world though. While with DC connected MPPTs I can just keep adding them to the system until it works even under heavy clouds and winter time conditions.

[@MiH1IT]

Andy, I use 280 Wp poly panels, two in series, 28.7 Vmp, 35.6 Voc (NOCT), 31.5 Vmp and 38.6 Voc (STC). I'm using victron smart solar, 48V 16S LiFePO4 battery and I'm getting 5 kWh out of 1 kWp a day. So I think that two panels in series is not an issue. It takes a few minutes longer to start after sunrise (mppt needs +5V), but that would not produce much anyway.

[@OffGridGarageAustralia]

But you don't have shading, right?

[@MiH1IT]

@@OffGridGarageAustralia These are installed on a balcony (vertical), they are facing SE. Some months they are slightly shaded in afternoon. Not at the moment and I don't remember exact numbers. Also because of the angles in summer they get sun from side/behind in afternoon, no direct sunlight and they still produce "enough". So, sure, shading will affect the output, but there will be always enough voltage for it to work, 3S is not necessary as it will be affected too and 2S means more smaller zones, so with some luck you will have more zones that are not affected at the same time.

[@wayne8113]

Thanks Andy

[@GeoffHou]

I would be interested to see if keeping the palm leaves or your sheet in front of the panel for 15m would trigger a reset of the mppt. According to what I could read victron tries to stay around the same voltage per mppt scan period and does a full scan every 10m. Would be very interesting.

[@OffGridGarageAustralia]

I have heaps of shading from trees and none of my 4 MPPTs has ever reset because of this. The MPPT tries to find the maximum power for this situation, regardless of what the shading or output of the panels is. I have not heard of a reset of the controller because of shading...

[@IXISSV]

Your single panel shading wont be an issue where you live, but I live in a terraced house with my panels in the garden. I do get 1 panel shaded as the sun is lower now here (UK) and the neighbours chimney stack shades 1 panel, then the next as the sun moves. So not totally unreasonable for some 👍 Looking forward to the install vids 😁🤞🥳🍻 But PLEASE wear proper footwear when up on the roof 👍😉🍻

[@OffGridGarageAustralia]

Yeah, you will have this hard shadow on your panels. Thanks.

[@excillisbank2611]

humm hate de voir la suite... très bon test.

[@evil17]

Good vid & commentary for consideration, its a quandary, but if the Victron MPPT Controllers do have a Boost/Buck type system built-in, I think that would be a suitable solution, or to boost each panel to a required output / input voltage of SCC could be viable, while boosting up & down is going to have certain inherent inefficiencies also for consideration along with more electronics and potential failure points. I have been experimenting with Maxwell Caps on each side of a 24v system controller recently, I dont know if this is something you would ever consider doing, Im doing it mostly out of curiosity & because I have a few big caps sitting around to play with, but It does have some benefits with shading conditions and when the batteries are full the capacitors can get up to 76v of potential which can push a lot of extra charge through ur controller when a large load comes on helping to reduce battery surge along with 2 more caps at the inverter. Always enjoy ur content. Interesting to see which way you go here and looking forward to it as well. Cheers

[@MarkPrince1317]

Good morning Andy 🌻🌻☕☕ that's very helpful video Thank you and best regards from Philippines 🇵🇭

[@OffGridGarageAustralia]

Thanks a lot.

[@KevIsOffGrid]

I'm excited for you, will be an awesome system, and should run the whole house too maximising your grid tie output from the house system. Will be fantastic :)

[@davegeorge7094]

Fall in the USA and spring for folks down under the equator. Andy's sun get higher every day now.

[@OffGridGarageAustralia]

Yes, the shadow in front of the garage will go away completely in December and January. Lot's of sun and power during this time.

[@LITTLEEXPERIMENTCHANNEL1]

Chainsaw was the first thing that came to mind.

[@pet870]

Das war mal wieder ein schöner Beitrag zum Thema Jugend forscht. Da sagt mal einer die Jugend von heute ist für nichts gut. Vielen Dank für die inspiration.

[@zbynekjuracek1038]

Hi Andy, shading is not always a bad thing, right? :) But for solar panels, I'd think about to use optimizers to get the maximum from each string.

[@OffGridGarageAustralia]

They would not work for my system. I tested them on some panels and it made it actually worse. Huge voltage spikes and most of the time a worse power output than without. In my experience it is not worth adding this extra complexity (and $$$) but rather add more panels.

[@leonhardtkristensen4093]

Hi Andy, your personal safety lacks a little. Sandals on the roof!!! Well who am I to say. I let my tractor run over my legs. I broke one leg. Anyway I wouldn't worry about only two panels in series. I have some old 250w panels (2S4P) that I play with at home in Melbourne and I got 9.162kWh today. My professional installed 3.6kw (capped a 3kW) 2 string system gave 20.2kWh in the same time starting at 08:00 and shutting off at 18:20 It was a nice sunny day today.

[@OffGridGarageAustralia]

Great, thanks a lot for sharing your experience with that.

[@rpsmith]

You don't need more solar Andy, you just need a good Chainsaw! :o)

[@OffGridGarageAustralia]

kzbin.info/www/bejne/pISaY3qmerRgsKM

[@loucinci3922]

Interesting. Thanks for sharing

[@OffGridGarageAustralia]

Thanks for your feedback.

[@jimbobarooney2861]

It's madness to increase your battery storage (44 kWh I think already), I would took at a system of turning on the full solar arrays in cloudy weather and turning off some of the arrays when sunny, I think you mentioned you would like 1000 watts input in cloudy weather, which I agree with that analysis, I am currently working on a viable solution for my own system, which I'm located about 54 degrees in the northern hemisphere, so there a big swing between summer and winter production, but I don't want or see the need to keep increasing my storage further, again so long as I can maintain 500-1000 watts worse case,

[@OffGridGarageAustralia]

Absolutely, Philip. 44kWh is a lot already. But if we want to connect the house at some stage, I would actually go a bit higher. The battery was full just 2 days ago but since then clouds and showers again so the battery goes down every day as production is not enough (it may be from next week though). This is all part of the huge test I'm doing; how much is too much and what do you actually need to make it work in a full energy off grid system including EV charging. I cannot see that there is a formula what to calculate all this upfront including shading, weather, season, EV charging, ... So I go ahead and see what is working. The current system is not enough for wintertime for sure. With the new system I'm expecting to get around 2kW under shading or cloudy weather. That's OK for the supply during the day and also charging the battery a little.

[@blackpearlphotos3529]

Considering what is going on in the world, I have decided to prepare due to what I feel are sibstantially increasing odds of electrical grid failure and fuel shortage along with food shortages. I have 60kwh battery as I want to ensure I can charge EV to stay mobile when needed.

[@martinly1050]

He can limit the charge current of each controller. That way the performance is not reduced during cloudy days and not too high when ot is sunny

[@jimbobarooney2861]

@@OffGridGarageAustralia 👍

[@OffGridGarageAustralia]

@@What11235 Thank you, that sounds similar to my situation. I'm sure I have to upgrade my solar as well even further to make it work in wintertime. For a few years now, we have so many clouds while before there was always blue sky at this point of time. Clouds are definitely increasing in this part of the world. So more solar needed.

[@JR-kk6ce]

Lesson learned -having had a direct hit by Hurricane Ian, always assume the worst. Keep your batteries and solar equipment at least 4 feet off the floor, and have some type of protection for your electronics from roof leaks.

[@OffGridGarageAustralia]

Oh, wow, sorry to hear that. Not much you can really do in such a case, I guess. Is it covered by insurance?

[@JR-kk6ce]

@@OffGridGarageAustralia Thanks for asking. I managed to save most of everything, except my inverter, which was going off like shotgun blasts every time a mosfet exploded, by lifting it to a top shelf while a 4 foot storm surge was breaking down my door. I still don't know how I managed to lift that heavy battery. It was a huge learning experience. No such thing as reasoning skills or remembering details when in survival mode. Insurance here, in the land of the not so free, is a joke. They set a low dollar limit on anything that can be considered a computer.

[@dc1544]

its nice to see how mppt controllers word in real life.

[@OffGridGarageAustralia]

Yeah, they work really well and fast. I'm always fascinated how quick they find the sweet spot of the panels.

[@danfitzpatrick4112]

You don't need more solar.. You need more chain saws! 🤣🤣🤣

[@OffGridGarageAustralia]

There is no way to cut these trees down, so need to work around it. And it's far more interesting if I can make it work... 😉

[@danfitzpatrick4112]

@@OffGridGarageAustralia Hell yes 😊

[@universeisundernoobligatio3283]

Looks like the blocking diodes are not doing much, get some 15A Schottky diodes and put them in reverse polarity across each panel. That way you can get all the amps from the uncovered panel.

[@energieundhobby]

Ja... es gibt immer was zu tun 😉 Das kenn ich nur zu gut... ^^

[@OffGridGarageAustralia]

Aber echt!

[@PatrickG60]

Hi Andy, ich habe an meine Batterie (48v 400Ah) den neue Heltec aktiv Balancer 10A gehängt um das balancieren zu Optimieren! Das Daly 250A kam da einfach nicht hinterher, das Daly merkt das Automatisch, Zellspannungen zeigt es allerdings dadurch nicht mehr an, aber laden und entladen läuft jetzt einwandfrei!

[@rogerandlyndabeall3840]

I use 36v panels charging 24v battery. In series no shading, 10% more watts than in parallel (less I2R losses) In parallel 10% less power full sun but if one panel is shaded, I still get half! So Parallel gives me more.

[@OffGridGarageAustralia]

Yeah, that is ideal. I want to make the test if this also works with 48V systems and how much power I still get out of this system. It's an experiment.

[@maxmeyer7299]

Feel free to do a few more tests with the shading from the modules, but please don't cover them completely, there isn't normally anything like that. But you definitely have a large parasol in sunny, hot Australia. The values ​​that I saw today with the palm trees made me think. I have a shadow on it through a dormer on the roof until noon... that seems to be really noticeable.

[@OffGridGarageAustralia]

Yes, a bit of shading makes a lot of difference. We will do more testing once they are installed on the roof. We can manually disconnect every single string on all 4 roofs.

[@SigmaOfMyParts]

your outdoor light is on in full sunshine. about 15:55

[@SolarizeYourLife]

It doesn't matter if you have two, three, or four panels. It's going to act exactly the same if you have them in series... I have a similar situation in my backyard. I get only three four hours of sun in the rest is all shaded so I have my panels only in parallel... I can only go 24 volt system...

[@OffGridGarageAustralia]

Yeah, a lot easier with 24V and only parallel panels. That is ideal.

[@andreaskoumides9599]

Hi Andy, just a thought about the charge controllers, what if you used the Victron MPPT RS 450/200? It has 450V open circuit and 200A charging and I believe it has 4 separate MPP Trackers. Surely the high voltage would be better in shaded conditions. Would be interesting to know what you think.

[@stanislavmlcuch2085]

Actually long string with partial shades decrease the power dramaticaly. In shaded condition is better to have as short string as possible, because you have half in the shade but other half in full sun.

[@OffGridGarageAustralia]

Not a good idea with all this shading. The efficiency will go down a lot and also the bypass diodes will work hard on these shaded panels. Both not optimal. I found the many parallel strings work the best. Even optimizers are not great...

[@gf-xy2of]

@@OffGridGarageAustralia Hmm, if the non-shaded panels in a string run at full power, then I'd not expect more than say 20W loss in the bypass diodes of each shaded panel, while the unshaded panels in the string can still be operated at their maximum power point. If panels have multiple bypass regions with a diode each, then an additional bypass diode across the whole panel could reduce the loss if the whole panel is shaded. Similarily, also groups of adjacent panels could be bypassed with additional diodes, in order to lose only a single diode-drop when the whole group is shaded (instead of losing one diode-drop per bypass region).

[@vickipps6821]

Thanks very interesting thank you for all your effort to help us I can't wait

[@OffGridGarageAustralia]

Thank you.

[@philiprsd]

If you do the test by using optimizers If one panel is shaded the other one wil work full

[@OffGridGarageAustralia]

Optimizers don't work well with existing MPPTs. I tested this and got huge voltage spikes. You then have two MPPTs working with one panel. I know there are other optimizers with constant current tech but you still have to be careful with that. I found the pure MPPTs can handle the shade the best. Andy you're adding more complexity and also more $$$ to your system for little gain. It is cheaper to add just some more panels to compensate.

[@pulith5220]

Because of your shading situation u need to get half cut solar panels so that when one half is shaded u would get more power from the other half. Also wouldn't it be better to go for bifacial it will generate more power also will not crack but you will hv to put a reflective paint on the roof to get best results. Mine work great even at low light. I got the Jinko solar panel model JKM535M-72HL4-TV. Ohh also if you can answer by below question about my inverter tripping would be great help. Thanks.

[@CollinBaillie]

In the first video testing these new panels, Andy shows that they are actually like 3 strings in parallel in the one panel already, so they have something similar to the cut cell panels. Hence the name shingled panels. Andy really is testing extreme sutuations.

[@pulith5220]

@@CollinBaillie yes true but it don't solve the cracking of the back panel. But I think these panels take up less space too. So bcz of that he could cramp few more panels n get more power. :)

[@OffGridGarageAustralia]

Yeah, with the new solar panels, I'll get 4kWp instead of 3.6kWp and have the legal free space around the panels.

[@johnallen3555]

3:30 into the video, yes, no shading from trees, but yes, shading from the leaves on the panels - wonder what the peformance drop from these leaves would be

[@OffGridGarageAustralia]

Literally no power loss from just a few leaves on the panels. Also, thorough cleaning makes no difference in power output. At least not measurable.

[@johnallen3555]

@@OffGridGarageAustralia thankyou

[@marcobrian1619]

Hi Andy, great clip with loads of information again . Wow your really upping your system?!!! As said before, I'm just going from 12v to 24v. But IV been thinking....... should I say f### it and go 48v ???? IV got 12 cells at 200ah at moment set up as 12v But IV got 20 more cells (again 200ah) on order. So I could do 4x24v banks Or 2x 48v banks??????? Hmmmm Just need more solar panels too.... But there getting like hens teeth here in UK, unless you pay stupid prices.. Least your out of winter and heading into summer. As you know we are the other way.

[@OffGridGarageAustralia]

Thanks Mark. It all depends on your load and project. If you only have 12V equipment right now and need to upgrade your inverters to 24V anyway, I would go 48V if possible. It is just future proof and regardless of what loads you will connect, it can deliver that. I heard about the panel shortage in Europe, that's not good... Used panels are probably even harder to get, I assume?

[@MegaCyrik]

Just wondering if you know about mppt boosters? You can charge just fine a 48 or even 72volt with just 1 panel. A normal mppt makes the voltage lower, but a booster on the other hand. Good for small EVs with a single 500watt panel on the roof at 30-40v but a 60v battery.

[@OffGridGarageAustralia]

Most of these optimizers have an MPPT build in and don't work with your main MPPT. I tested this and got huge voltage spikes as the two controllers fight over the max power point.

[@MegaCyrik]

@@OffGridGarageAustralia ? Why would there be two? *Edit* ah, think you are replying to that other guy talking about optimisers, but hit the wrong reply button ?

[@OffGridGarageAustralia]

@@MegaCyrik Yes, that is correct, sorry. Booster chargers are not really available. I have only seen a 10A version so far.

[@MegaCyrik]

@@OffGridGarageAustralia yea 10 ah is quite normal. But if you only have 1 or 2 panels, having 20,30,50 or 100a would be useless :) if you had more panels, you would not need a booster. 10A on 72volt to a 60v battery, is still 720watt :) basically... Normally with mppt you have high voltage (60-500) that you reduce by increasing amps so it can go into your 12-48v system. So you need a big amp mppt. But, when your voltage is low, you increase the volt by reducing the amps. so 10a should be enough. You won't need a 60a booster for a 18v 1,5a panel charging a 48-60v battery :)

[@bruceyv83]

Interesting to see the huge drop with only a little shading. It would be interesting to see a similar test but with an optimiser hooked up, would they help?

[@OffGridGarageAustralia]

No, they are not magic devices. They will 'optimize' the power output with their internal MPPT. This clashes with the MPPT you're using. I have tested with solar edge and got huge voltage spikes but only a bit of gain in power at some stages. Not enough to justify the extra expense I would say.

[@bruceyv83]

@@OffGridGarageAustralia thanks Andy, keep up the good work.

[@aeronsongerson2416]

In conditions of regular shading, would it make any sense to put a diffuser panel in front of the solar panel with a gap? So instead of hard shadows and bright sunshine hitting different points of a panel, which they seem to not deal with well, like you have with the trees, you could have instead an averaged light level across the whole panel?

[@OffGridGarageAustralia]

But then you would lose out when you have full sunshine. It would make a difference in permanent shade but if you have both you would need a mechanic to remove and put it back in place if needed. And it would need quite far away from the panels, several meters at least.

[@niki1541]

Great experiment as always. I have a suggestion if I may. Many of us have roofs facing east-west which is not ideal but still usable. I can not find any real life data on how good Victron MPPTs handles panels on opposite side, east-west orientation. Eg. if you have one string of panels (xS) that is acceptable for a certain MPPT connected to MPPT and then connect same amount of panels (xS) from other side of roof to that same MPPT in parallell. You will get xS2P but those two stings will never produce same amount of energy at the same time and I guess this setup could be considered as xS1+P. My question is will this setup produce less energy then if used two MPPTs, one for each side. How big is degradetion if any? Well, who would be right person to check this but Andy.

[@MrJayrot]

Hello Sir Andy, I got 2S 2P Solar Panel Configuration with Imp13.01 per string, Do i need to add on Fuse per string.

[@Dasol0246]

Andy, Does the temperature an humidity affect your Batteries and electronics where you are in Australia? I’m thinking of installing a solar system with 48vdc Lipo4 pack, we have high humidity and high temps, what’s your opinion? Love your channel.

[@JulianGoesPro]

Sorry for asking so bluntly, are you from Germany? Love your vibes!

[@OffGridGarageAustralia]

Have a look at my other channels 😉 Link is in the description...

[@wva5089]

I Love how you measure everything.. but I don't love how you don't theorize.. for example: area of a panel: 1.646m*1.140m=1.876m^2 .. two would be 3.75m^2 your sun meter showed 1200w/m^2 so from the area the panels are taking up.. your producing 720w 15% efficient? prolly cause of the heat? I know you like the victron mppt's.. but I think they take shading poorly. best case scenario you should expect 360watts from one of the panels being 100% shaded. Instead you get 129w.. ouch. so either the bypass diodes or the mppt has lots of room for improvement. Can I send you money to buy something on aliexpress to try adding to your two panel setup? I'd like to add an unlocked solaredge optimizer.

[@evil17]

It would be interesting to find where all these lost watts are going and what inefficiencies can be found in what area’s of a particular system. Thanks for offering Andy a microinverter to play with and test, I am curious about how overall efficient these devices are, as I have come across a large scale 122kW Solar crypto-mining setup on a farm in America, who was taking down his micro inverters and changing over to a String setup because he had some issues with the inverters and they are not always in a location that is easy to get for maintenance or replacement and he sometime had to dissassemble large sections for otherwise relatively minor repairs/replacement. I believe he stated that they were becoming untenable due to reliability & maintenance issues, where I guess the maintenance issues could be mostly overcome through good initial engineering & planning, but he had them for some years now also. I came across this guy’s fantastically huge setup on Will’s DIY forum, it was an excellent review.

[@CollinBaillie]

I think Andy has shown he has a micro-inverter for testing in previous videos.

[@OffGridGarageAustralia]

Guys, how do you use micro inverters in an off-grid system??? Once the batteries are full, you have to turn them off somehow, control them. Yes, the Victron MP II can handle that up to a certain size (google Victron 1:1 rule). I need this AC capacity for when we connect the house (+10kW of solar). I can add as many MPPTs as I want. There is no limit. And let me tell you, I have tested quite a few MPPTs from other brands and they all suck. I'm not a Victron fan boy nor do I get anything out of that, but they have the best system and devices in my experience.

[@FutureSystem738]

@@OffGridGarageAustralia Agreed Andy 👍

[@CollinBaillie]

@@OffGridGarageAustralia I'm sure there are grid-forming models. Of course what do you do to curtail excess then? Also, you'd have to have an AC coupled battery, which is extra expense. Possibly DC optimisers for each panel, but again how do you control them? How do you curtail excess generation? It's simple to say "micro-inverters are the way to go" if you don't consider the entire system. Opinions... So many out there.

[@dama054]

Quick question do your individual pack drift much I have 3,packs of 280ah cells one on a jk BMS one on a seplos BMS and one on a jbd BMS and they have all got different capacities showing even though they are all connected to the same bus bar the seplos BMS is the worst one showing the least capacity do you have the same issue

[@OffGridGarageAustralia]

The actual packs don't drift at all as they are constantly balancing against each other. The SOC estimates in my 3 BMSes however, are all different. That's why I use the smart shunt as point of truth and it is pretty precise.

[@dama054]

@@OffGridGarageAustralia yes that was going to be my next move to try and get some accurate idea of remaining capacity of the whole packs

[@edwardbyrd7667]

At 3:30ish I got to wondering. Is the bird poop a material shader?

[@ricardomarcelino8388]

Ahahahah... "I need more panels to power my battery"... I need more batteries to cope with more panels... I think you are getting into a vicious circle Andy... Let me guess what comes next... 🤔🤔🤔😁😁😁

[@OffGridGarageAustralia]

We have to test in between! If we want to connect the house at some stage, we need to go big...

[@ricardomarcelino8388]

@@OffGridGarageAustralia Definitely. More content for us 😁😁😁

[@52gulfpapa]

Did you consider the Victron SmartSolar MPPT RS 450/100-Tr or 450/200-Tr for the new panels?

[@OffGridGarageAustralia]

No. I have too much shading for them and most panels would run very hard on their bypass diodes. Having many smaller strings in parallel is more efficient But I still have to make this test 😁

[@nathanclemens7577]

Can run solar panels with out a inverter can I run straight to fuse box or no is there a way to make home inverter

[@awesomedee5421]

I don't think you have enough panels. You should go get more. :)

[@OffGridGarageAustralia]

I think so too... 😁

[@stefanschindler8959]

Andy - your custom widget on the VRM does not have your changed ID´s included yet. still showing 288+290 ( they are offline) :)

[@OffGridGarageAustralia]

I can't get them to show any more. I deleted the widget and recreated it. Now it shows only 3 of the 4 MPPTs.

[@s.v.s.e]

Dear sir kindly guide me one thing. I have 8 cells 3.2v 32650 lifepo4 6ah each. I want to make 12v 12ah . 2 series of 4 cells each and they will be parallel. I purchased 60A dally bms which has 4 red and 1 black Ballance wires. Now i have 8 cells i am confused about balancing wiring kindly guide me . Cells are 8 but Ballance wires are 5 only

[@OffGridGarageAustralia]

You would need a second BMS for the other string of batteries. One BMS can control 4 batteries only. 2nd option is to connect 2 batteries in parallel first (they act as one cell) and having 4 of these twin packs in series. Then you need only one BMS.

[@s.v.s.e]

@@OffGridGarageAustralia thanks

[@s.v.s.e]

@@OffGridGarageAustralia can i get your WhatsApp number please

[@OffGridGarageAustralia]

@@s.v.s.e I cannot do any personal consultation, sorry.

[@jadu79]

One thought I got when I watched your videos is why you don't make a pool roof out of panels as they seem to be in the sun a lot and if you cover there you get more shade over the pool and then you can keep some panels on the roof. Realize that parts of a scaffolding need to be built but it looks like what you have over the pool is now in steel so put a rail on it and if you still need to buy more controls then why not 200-250v so you can put more in series? Another thing I wonder is is it better to put many loops or connect them in series parallel? (if you take 3 in parallel and take two of those in series then they should have a little more security to produce even in partial shade or am I wrong there?)

[@OffGridGarageAustralia]

It's only for a while that it is in full sun. And I would need to replace the whole structure to support the panels. Not an easy task and quite expensive as the pool is underneath and you cannot use a ladder to get there... You cannot connect three panels in parallel without proper fusing as the reverse current per panel is limited. The design is that three panels (only two from next week) are in series and next to each other in one row. So, the shading for this one string is fairly even and consistent as much as possible. If I have two rows in series (3 per string), one of them would be shaded and the other one not. The MPPT tries to optimise that setup but it is more efficient if these rows are in parallel and not series under shading conditions. It's a bit complicated without a drawing so a video will be coming about that...

[@kennthbrowne7051]

love your video nice 🥰🥰🥰🥰 i have 3000 Watts 48V inverter i have 48V solar charger for it 30A what size panel i should used

[@OffGridGarageAustralia]

That solely depends on your solar charge controller. It will tell you in the specs what panel size you can connect.

[@jimmyg6215]

Andy any thought in getting a 450/100 MPPT charge controller from victron and setting up a portion of the system with that charger and using your other chargers as they are for now? Just a thought.

[@OffGridGarageAustralia]

No, too much shading for the RS MPPT. It is not efficient as most of the panels will be shaded all the time and the bypass diodes will have to work hard. That was part of my design to have many parallel strings so shading affects only a few strings but not the ones in full sunlight.

[@rtw8972]

Why have I never seen an installation of solar panels that are mounted on a device which lets them actually the sun? Having them actually looking at the sun wouldn’t give more total output in the whole day?

[@rtw8972]

Actually let’s them track the sun’s movement from horizon to horizon.

[@team13thirteen]

Servus Andi, can you test something for me... whats happening when you mix auf panels in the string... 375w and 240w Panels... (Trina Solar) 34.4, 10.8A vs 30.4V, 7.89A Panels... you can test that easy on your Victron MPPT's. Voltage would be added but what happens with the string... only 7.89A? Fronius Inverter has a perfect Shadow Management - i testet that... it is amazing - it is locking for the best MPPT point with dynamic power point tracking... it is like shaded panels when you mix it up :D

[@OffGridGarageAustralia]

The larger panel would try to push its higher current through the smaller panel and will heat it up. Certainly not advisable to mix such panels in series.

[@justinreynolds9669]

I got the solar bug bad now. I am going from a 12 volt system with 2kw of panels to a 24 volt system with 6kw of panels next spring. I am going to have to do it slowly by purchasing racking first then more panels and then an upgraded inverter after that. It will take me 4-5 months to purchase everything and then 2-3 weeks to do the upgrades.

[@maukaman]

If you are planning on increasing your system you might want to consider holding off on buying a 24v inverter and instead plan on bumping your system up to 48v instead.

[@OffGridGarageAustralia]

6kw at 24V will be 250A. The sounds like pretty big cables. Yeah, I agree, is a 48V an option?

[@justinreynolds9669]

@@OffGridGarageAustralia 48 volt is an option but just batteries alone would be in the 1800 - 2000 dollar range for 280ah batteries since I would need 12 more. I am already oversized on cabling for my current system i am using 4/0 cables to everything that i can other than the current inverter. When i go to the new setup it should only be 2 new cables. I want to oversize the solar to start out and add in more inverting capacity when funds will allow. I also only plan on in the near future having around 4kw of solar with the option of my scc being able to add 2kw more when funding permits.

[@EpicWinz]

I think you need to buy a chainsaw and do some “pruning” 😂 1:02

[@pr5991]

How much did they cost HiE-S400UF?

[@MiH1IT]

Guys, anyone know where to buy Noark DC breakers in Europe? Can't find it anywhere. Or any other brand (not noname/chinese garage company) with 100A DC breakers to which I can add shunt release. I want to use shunt release, so can't use fuses.

[@highlander2330]

Unrealistic shading in Australia, but not in Germany, when one panel is covered with snow ;-)

[@OffGridGarageAustralia]

Then you have clouds as well and production is pretty poor anyway. And there will be still some light coming through the snow if the sun come out all of the sudden. But yeah, that's a real scenario...

[@aleksanderstrommer7677]

Offtopic but can I charge the normal agm pb battery with battery charger while solar charge controller and inverter are connected?

[@allornothing7957]

Yes

[@OffGridGarageAustralia]

That's a yes from me, too.

[@margarita8442]

what is the chance of solar panels catching on fire ?

[@OffGridGarageAustralia]

Fairly low if you factor in the allowed reverse current and proper fusing.

[@OffGridandOutdoors]

I was trying to do that, but the vdc input to the scc was not hi enough

[@OffGridGarageAustralia]

Yeah, depends what panels you're using. The 60cell panels have only like 29/30V in the mpp. The Hyundai have 41V per panel so that works quite well actually.

[@curtismckinney7076]

Try using solar edge or tigo optimizers

[@OffGridGarageAustralia]

I tried solar edge and they made it all much worse. Huge voltage spikes and only very small gain, if at all. It's easier to just add more panels...

[@steffen1182]

shading, shading lady 😁

[@pulith5220]

Hi I got a problem. I hv 2 inverters running parallely and both hv RCCB for the output and as soon as I on both inverters and I draws over 1amp current the rccb trips this only happens when running in parallel mode. When I run the inverters individually thr RCCD don't trip. Can u give me some advice why this might be happening

[@OffGridGarageAustralia]

Are the inverters properly in sync? What inverters are they?

[@pulith5220]

@@OffGridGarageAustralia they are EAsun inverters. I see the master n slave marks on the 2 inverters but I assume it's something to do with them not linking properly

[@pulith5220]

@@OffGridGarageAustralia after looking at my wiring I found out what I hv done. I was using 2 RCCB for the 2 inverters, 1 rccb each. So inverter 1 and 2 AC out was connected to the rccb tops side. From inverter 2 rccb bottom I took the wire n then linked it to inverter 1 rccb bottom n from there to the change over switch. Since I brought the inverter 1 rccb to the bottom that was the mistake I changed it to the top then all was fine. Its hard to explain but all is OK now. 👍

[@OffGridGarageAustralia]

@@pulith5220 Ah, there you go. Great, you figured it out and it is now working.

[@martinmooren9536]

13kW solar means you're three battery banks are fully charged from zero in 3,5hrs 😄 But even with powerwall 2.1 and 2.2 you still have a lot of energy left. Maybe time for a public car charging station in your driveway 😄, or other plans with the remaining energy (besides powering you home)?

[@OffGridGarageAustralia]

Not quite because these 13kW are only present during noon time. As you have seen in the video, the big shed was in full shade while the carport was still in sun. In the afternoon it is the other way around. I will have heaps of power in summer for sure but the system needs to deliver in winter to go fully off-grid. That will be the interesting time for testing. But we first look forward to lots of energy during summer and a full battery every day for a while. Also looking into buying a second EV next year...

[@martinmooren9536]

@@OffGridGarageAustralia You are right Andy about the shade. My solar system has also shade from the left and the right side and wil only output it's maximum power for one hour. Winter will be an interesting period to cover the energy needs. A new EV, nice! It would be nice if you could use the EV as energy storage and extract power from the battery also to power the garage. But I'm not sure if and what brands provide these kind of features. Interesting for sure!

[@igorkvachun3572]

Yes👍🔋 ⚡🔌💡

[@markbrettnell3503]

Considering you are 2nd guessing things like I do, because it's a new idea from what we are used to running, hook up a string of panels on the car port roof to compare to the existing setup. Makes for some more video's and also can settle down the uneasiness to see side by side comparisons. Plus that way you can get used to the new setup and see how it responds before the insane work of tearing out the existing solar to replace.

[@OffGridGarageAustralia]

That would mean a major change in my system design, and I would need to invest in at least one new solar charge controller (Victron RS) just for testing purposes. That's a lot of costs which I rather spend on the new installation.

[@markbrettnell3503]

But don't you need to upsize your existing charge controllers for these new panels anyways? Plus you had mentioned in the video that you were considering adding panels on the carport anyways. At least if you do it that way, you would have another roof covered that is pulling in power. Plus I'm pretty sure that there are several more people besides me that would greatly appreciate seeing more real life set up of side by side comparisons. Hell, you got me thinking about trying them here in Canada to see how they compare to the traditional 60 cells I'm already running myself.

[@OffGridGarageAustralia]

@@markbrettnell3503 I will have 4 MPPTs eventually, one for each roof space and panel orientation. The 70A MPPTs I already have right will still work with the new 4kW of panels. The big shed and car port will be smaller solar installation, but I got the same size controllers for these two roofs.

[@waltsteinchen]

I do not understand why you do not simply 3 panels in series ? .. Since the cables are typically long enough . that should not be a problem ... I just did similar on my new system ...

[@Sailing-Aquaholic]

Three panels in series would give a to high voltage for the mppt to handle. I thought Andy explained that in a previous video

[@evil17]

@@Sailing-Aquaholic I dont think it is that the voltage is too high, i think Andy said it was because the roof awning area isn’t wide enough to take 3 panels wide strings.

[@mikakimi2558]

sir, can you review MPPT BOOST SOLAR CHARGE CONTROLLER ...I use 120Watts Bosca solar panel... controller only outputting 1.3 amp set to 57vdc for charging 48v 20amp lead acid ebike battery.

[@mikakimi2558]

used 300watts controller

[@chrisloving6647]

Is your main battery braker going to handle that?

[@justinreynolds9669]

I think his will because it would be ideal conditions to get the maximum output of the entire system. He will have shading here and there and that will affect the total system amperage during the day.

[@jogi_54]

You should never connect the 2 roofs together, because in case of a Lightning strike, you will have this on both roofs... Better: you connect each roof down and to a multiple earthed ring on the ground. Dehn Blitzplaner will help you ;-) Any questions ? - than ask... But - in general, why do you fear lightning strikes at all ?? Around your roofs, there are so many high trees, that it is nearly, I would say, totally impossible, that you can get any lightning strikes on your garage roofs. Anyhow, to download the Blitzplaner, it is the mich easier way to try it at the Austrian homepage of Dehn.

[@CollinBaillie]

I believe the consideration is almost always a near-by strike, which still have potential to cause a spike in any equipment, not just the solar panels. The SPDs used in solar systems are more about atmospheric transients than direct strikes. To arrest a direct strike would seem to require a much more serious protection setup, and is probably unrealistic to try to achieve.

[@OffGridGarageAustralia]

Can't recall having mentioned anything about lightning in this video 🤷‍♂️

[@CollinBaillie]

@@OffGridGarageAustralia Jogi raised the issue in the first comment... 🤷🏻‍♂️

[@netrocker9990]

Connect two panels in series with blocking diode on each string

[@OffGridGarageAustralia]

No blocking diodes, they are not necessary. There is no reverse current between shaded strings and sunny strings. Both are charging the battery. I made a few videos about this and showed the effect.

[@mickm68]

Andy, Sorry but i believe you have an issue with Isc. In the spec sheet you displayed each panel had a Isc of 10.12A. If you do 2s 5p then you in theory have a Isc of 50.60A. The Victron spec sheet for your controllers have a MAX Isc of 50A - with a foot note of possible damage if exceeded. ~ Victron's polite way of saying void warranty

[@OffGridGarageAustralia]

I saw that and it is factored in. So far, the MPPT are limiting the current if exceeded. In fact Victron says, solar panels can be overprovisioned up to 133%.

[@mickm68]

@@OffGridGarageAustralia I agree with your comment about overprovisioning in fact you probably could go a lot higher with overprovisioned/over paneling. However with or without over paneling you have to ensure you do not exceed Isc.

[@mickm68]

Andy, i will correct myself - i used Victrons online MPPT calculator and it only cares about Imp even though it warns about Isc in their datasheets. Up to and including Isc 50 (5 * 10) it allows your existing controller as your array of 2s 5p in theory max out at 48.8A.

[@Investfloes]

There is no wind there? The wind doesnt have a shadow xd.

[@zjzozn]

🎉