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Bluetti AC200P vs BattleBorn/modular

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Noob here just starting out with the goal of an off grid boondocking system in my 22ft trailer. Go easy on me!

I have a friend who knows a lot more about all of this than I do and they have been helping me figure it out.
Their recommendation: Instead of building a system from scratch with Battle Borns/Charge Controllers/Fuse panels, use a couple Bluetti AC200P one for each major workload. 2-3 Bluetti AC200P would be safer and more reliable than a beginner building an entire large system from scratch.
My question: Is that really an effective solution to run some decently large workloads? I'm nervous that each bluetti won't necessarily be able to keep up with their individual workloads for longer periods of time. Has anyone done this and what has your experience been?
Other components: 12 Rich Solar 100 watt Poly panels (Not doing tilt, just flat mounted to roof of trailer), trailer is a 22ft aluminum siding 1963 Boles Aero. Ground up rebuild so the ceiling has R13.1 and the walls have foamular R5, pretty well insulated, Henry's cool seal on roof below solar panels. 10-12 recessed LED lights throughout. Have not purchased yet but plan to purchase soon and want to be able to run: Window style Air Conditioner, high efficiency chest fridge/freezer, and microwave (Please feel free to share recommendations, leaning toward a dometic chest fridge/freezer combo, and just a high efficiency AC unit).

So my original plan was just to buy 4-5 battle born 100 AH LiFePO4, cover the roof in solar panels, and run a 2300 watt generator occasionally when necessary. The friend who is helping me figure this out has had bad experiences with home built systems and I'm not an electrician so I like the idea of an out of the box self contained system like the Bluetti that will monitor temperatures itself and tell me in an easy to understand interface if something is wrong. I'm thinking of just attaching 6 panels to one bluetti and 6 to the other and then having Air Conditioner on one Bluetti and fridge/microwave/12v fuse panel to lights, ceiling vent fans, and small electronics on the second.

I know there's a ton of unknown variables here like how much sun exposure the roof will have, exterior temperature where I'm parked, but I'm just wondering if anyone has faced this decision and what direction they decided to go, any lessons learned, etc. Thank you Will for your awesome videos and for creating this community!
 

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Noob here just starting out with the goal of an off grid boondocking system in my 22ft trailer. Go easy on me!

I have a friend who knows a lot more about all of this than I do and they have been helping me figure it out.
Their recommendation: Instead of building a system from scratch with Battle Borns/Charge Controllers/Fuse panels, use a couple Bluetti AC200P one for each major workload. 2-3 Bluetti AC200P would be safer and more reliable than a beginner building an entire large system from scratch.
My question: Is that really an effective solution to run some decently large workloads?

Welcome to the forum.

God no. Portraying Bluetti as reliable is a stretch. Lots of issues presented on this site coupled with tales of very poor customer service and difficulty communicating with the company.

I'm nervous that each bluetti won't necessarily be able to keep up with their individual workloads for longer periods of time.

Good instinct. AC200P also have high idle consumption and waste a lot of their capacity just by being on.

Has anyone done this and what has your experience been?

I haven't.

Other components: 12 Rich Solar 100 watt Poly panels (Not doing tilt, just flat mounted to roof of trailer), trailer is a 22ft aluminum siding 1963 Boles Aero. Ground up rebuild so the ceiling has R13.1 and the walls have foamular R5, pretty well insulated, Henry's cool seal on roof below solar panels. 10-12 recessed LED lights throughout. Have not purchased yet but plan to purchase soon and want to be able to run: Window style Air Conditioner, high efficiency chest fridge/freezer, and microwave (Please feel free to share recommendations, leaning toward a dometic chest fridge/freezer combo, and just a high efficiency AC unit).

A/C - even in high efficiency/low power configurations - can be very demanding.

So my original plan was just to buy 4-5 battle born 100 AH LiFePO4, cover the roof in solar panels, and run a 2300 watt generator occasionally when necessary. The friend who is helping me figure this out has had bad experiences with home built systems and I'm not an electrician so I like the idea of an out of the box self contained system like the Bluetti that will monitor temperatures itself and tell me in an easy to understand interface if something is wrong. I'm thinking of just attaching 6 panels to one bluetti and 6 to the other and then having AC on one Bluetti and fridge/microwave/12v fuse panel to lights, ceiling vent fans, and small electronics on the second.

I know there's a ton of unknown variables here like how much sun exposure the roof will have, exterior temperature where I'm parked, but I'm just wondering if anyone has faced this decision and what direction they decided to go, any lessons learned, etc. Thank you Will for your awesome videos and for creating this community!

Rather than one less expensive component-based system that can be maintained and serviced readily by replacing individual components, you're proposing 3 self-contained relatively inefficient units where if any single part of them go bad, you have to replace the whole thing.

Splitting your solar means if you're not utilizing the power they're tied to, the solar is unavailable for other needs and may be wasted.

While I respect your friend's bad experience, it is very atypical for a well-planned out DIY system. Sure. Components fail, but you can almost always recover quickly with some backup option and restore it to full function relatively quickly. I have a big 48V system, but I also have my old "learner" 24V system sitting around with the batteries on float ready to provide very limited backup power if needed.

More important at this point is to establish both your resources (link #5 in my sig) and your needs (link #1 in my sig).
 
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Thank you for the feedback and links! I appreciate the help very much. I'm looking back toward a component based system now. I agree with the major concern that a silo'd system won't effectively take advantage of the solar input which was a concern of mine.

According to the off grid king list of materials, I should use one Rich Solar 40 AMP MPPT Charge Controller for every 4 panels. With twelve panels, should I just order three of these 40 AMP MPPT charge controllers? My open circuit voltage is 22.6v x 12 panels = 271.2 open circuit volts and 5.41 max amps per panel. If I'm understanding, that's a huge demand for one solar charge controller so it seems like it's cheaper to break it up into three loads and then just connect all three of those to the battery bank, am I on the right track here? Just duplicating that blueprint x3 so three 30a in line fuses, 3 bluetooth modules, 3 solar panel connectors and Y branches, would it be cheaper and more reliable to just get one higher end solar charge controller that can handle all 12 panels?

I was planning on doing a 12v system because all my LED recessed lights and other components are 12v.
Thanks again for the help! Super appreciate it.
 
SCC are rated by CHARGING CURRENT and need to be:

Array Watts/battery voltage = SCC amps

e.g., 1200W/12V = 100A

Going a little low is fine, even 10-20%.

It's not based on the # of panels, it's based on the charging current. That same controller could handle 2X the array power on a 24V system and another 2X on a 48V system.

You don't just series panels willy-nilly. In general, you series them until you approach the SCC's PV voltage limit (with a 10-20% buffer) and then you parallel groups of strings together, e.g.:

12X 100W panels.

6S2P array: Voc 135.6V (probably okay with 150V PV limit if cold weather isn't a concern), Isc 10.82A

or

4S3P array: Voc 90.4V, Isc 16.26A

etc.

If partial shading of panels is a concern, you want less series, more parallel. If you shade ONE panel in series, you impact the output of all panels in that series. Shading of parallel panels is much less of a concern. You could conceivably parallel all 12 panels. The only issue would be wiring efficiency losses, but if partial shading of panels is a risk, it might be worth it.

Higher PV voltage SCC tend to be more expensive, less flexible and less shading tolerant.

The higher the PV voltage is, the greater the losses in converting to battery voltage. It's not a lot, but it can be a few % when making big steps-down.

1200W input is pretty stout for a 12V system. A 24V system would allow use of a smaller charge controller, powering 12V loads is as simple as a $50 24-12V step down converter.

Lastly, if you don't need to use 100W panels to "Tetris" 1200W on the roof, you may find 3-4 large panels more practical and more cost effective.
 
Ok now I'm sold on moving to a 24v system LOL. I already have the 100w panels tetris on my roof and I think they fit well so I don't want to have to return them and start over. I appreciate how detailed you're being, I just don't know enough about this stuff and feel like I'm out of my league. I tried to follow Will's off grid king blueprint but was able to fit more panels but that would mean the third solar charger controller and now I'm learning there's disadvantages to wiring them in series vs parallel. Idk, this is all a little intimidating, just want to be sure it's safe and somewhat reliable. Probably the reason Bluetti was so attractive.
 
Bluetti would have the same issues. Their charge controllers are fairly limited.

It's about roof protrusions. If your roof protrusions will shade your panels, you need to plan for it. With 24V, you'll need 2S for sure - 3S will probably perform a little better, so 3S4P is likely a good compromise. Arrange them in groups of 3 such that all groups are subjected to the same amount of shading where possible. This way if one 3S string of panels gets partially shaded, the other 3 parallel strings will still perform well if unshaded.

It can be intimidating, but following the blueprints and asking questions helps!
 
I just realized you already posted a picture of the roof layout... derp. I only see 10, but I think you can get them on there.

Your protrusions aren't too bad, and shouldn't impact your output for the majority of the day. 4S3P would work as well.
 
Yes! There was a bit of extra room so I ordered two more which haven't arrived yet. Awesome! Thank you for the help!
So this is awkward but I swear I googled it and can't find an answer... what does 4S3P mean? Just living up to my username.
 
3 groups of 4 panels wired in series, then those 3 groups are put in parallel with each other, so your Vmp is 4X one panel, and your Imp is 3X one panel.

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Ok GOT IT that actually makes sense which is shocking to me. Thank you for taking the time to explain it. Do you have like an amazon wishlist I can contribute to or an onlyfans or something? (haha but also not kidding)
Ok so that woul dmean all three sets are running parallel once they're strung together so they'd be going into one solar charge controller, right? Any recommendations?
 

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Yes, one MPPT SCC.

1200/24 = 50A. Will recommends several here:


I only recommend Victron, but that's because I'm a snob. :)

A Victron 100/50 would work nicely, but you would need to go 3S4P since 88V is a little too close to 100V.
 
I'm also a snob so I picked the Victron Energy SmartSolar MPPT 100V 50 Amp 12/24-Volt Solar Charge Controller (Bluetooth).
Would the 150/45 be better for any reason? I understand it has a higher voltage limit, seems like that would only be helpful in the future when panels get better and I can add higher voltage panels but 50% price difference, is it worth it for any other reason?

Ok sweet. That answers that side of it and I REALLY appreciate the help. What size breaker should I have interrupting the solar panel + and charge controller? Any good videos Will has made on how to set up the batteries for a 24v system? I already have two 12v BB10012, I know I can wire them together in a way to make them 24 volt but new territory as I had been planning to keep it 12v up until now.
 
The 50 and 45 numbers are the charge current, so the 100/50 has greater charging capability of a 24V battery than the 150/45, BUT the 150/45 can charge 48V and host a notably larger array if you want to over-panel it.

Given that you've pretty much maxed out your roof space, I'd stick with the 100/50.

Something to consider is if you want to utilize shade for comfort, but you still want to have some solar is to get a deployable array of flexible panels. A user made some custom frames from PVC pipe here:


You could get 3 in series and then just connect them in parallel with your roof array and deploy them outside of the shade for 300W of glory.

If you go with that option, look for ETFE coated panels with 5+ year manufacturing warranties and 20+ year performance warranty. The non-ETFE coated panels don't last as long; however, since this is an array that is only deployed when needed, they should last much longer than flexible panels constantly in the sun.

Batteries: first, you will need to parallel your two 12V BB and then charge them to 14.4V. This will equalize the batteries to both be at 100% SoC. You would then simply wire them in series for 24V. BB recommends repeating the 12V parallel charging once per year. I recommend 24V balancers:


This connects to both batteries and MOVES charge from the higher voltage battery to the lower thus keeping the individual 12V batteries at the same voltage. IMHO, it should eliminate any need to parallel charge them annually.
 
Ok got it. I'm going to add 3-4 more BB before I'm done so is there a version for balancing more than two batteries?
Any input on the circuit breaker question? Any recommendations on the 24 to 12 v step down you mentioned earlier?

I like the idea of having a deployable additional stack of panels but I don't want to invest in that until I've tested this system and figured out where/how much it falls short of my needs.
 
With 4 strings, you should technically have a fuse or breaker on each string equal to the "Max fuse" rating on the panel sticker (probably 10A). Easiest would be to use a MC4 fuse in each string.

Assuming 3S4P, that's going to be about 24A. You want a 1.25X safety factor, so 1.25 * 24A = 30A. A 30A fuse or breaker between the entire array and the SCC. This tecnically isn't necessary due to the fusing of the individual strings; however, this can be a very effective switch for completely disconnecting the array if you ever need to.

You'll need to add batteries only in pairs. When you order them, you should notify BB that you plan to series them for 24V. They will select optimally matched pairs. You will simply parallel charge each new pair as 12V to 14.4V, series them, and then add to the existing bank when the voltages are within 0.2V.
 
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