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Bluetti AC200P AC200 As Fridge Freezer Backup + UPS + Keeping it Topped Off

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Hey guys! I've been searching this great forum for everything related to the Bluetti AC200P which I'm getting in the next week (I'm including the word AC200 for easier search result purposes) ;)

I mostly got it for emergency outages... which are becoming more frequent and longer in the San Francisco Bay Area :(

... and the main purpose will be for keeping two fridges and a freezer cold. I've been measuring the power peak usage and total 24hr. consumption, and from what I can tell, I should be able to manage this just fine with a combo of over-paneled solar + short bursts of gas generator (hopefully the latter not needed).

The manual for the AC200P says to use / charge it every 3-6 months... which sounds like a bit of a pain for me to remember and do, so I had a thought to run by y'all:

Should I just use this unit as my main power supply for my PC and keep it topped off with solar?

Basically, a sort of "UPS" (I know, it's not really a passthrough UPS, but it would basically be used to power my PC 24/7) that would ALSO keep the unit topped-off 24/7?

... but I'm not sure this is a good idea, would even work... and if it does, would it be a bad idea to have it on 24/7 for years. i.e., bad for the batteries, inverter, charge-controller, etc?

I've been measuring my computer system's consumption and it's using about 1.5 kWh / day. I could use my overpannel setup to easily keep the system topped-off and full. Sure, it would dip about 1/3 by the end of the night when the sun is down, but I'm willing to accept that risk. (if this becomes an issue, I'll simply add some external lifepo4 battery packs to increase the runtime... and bust out the gas generator if needed).

So, what do you think? Doable? Bad Idea? Bad for the unit? ⁉️

Thanks!!!!
 
The Solar Gods have shined down upon me!!!!!!

I don't love the low-wattage old panels my friend was going to give me. Just too many would be required (9 in a 3x3 arrangement), so I was feeling inspired to purses craigslist for some better solar panels.

Well, I struck GOLD!

Someone was selling 4 brand-new REC 360 Watt panels (some minor scratches, but I tested them and they are working just fine). They usually sell for around $300, but I got them for $100 each! That's even cheaper than the used SanTan solar used panels of lower wattage!!

My the Bluetti 200P that should be arriving in the next few days is going to LOVE being matched with these in a 2x2 config!

1624659499573.png

1624659525147.png

So, any thoughts on my original question regarding using my Bluetti 200P as my main power supply for my PC to keep the unit constantly charged / topped off?

Thanks!
 
The beauty arrived!!!

1624915196961.png

It came 66% charged around 5pm. Just enough sun out to plug it into my new solar panels to get it to 100%!

BTW, these panels are NO JOKE! Messing with this level of voltage (80 VOC) and amps (18-20 A) is not something to be careless with.

I've got the panels on the ground while I test things and also prep / build a shed, which they will eventually be atop.

It's crazy to see how much a little shade can throw everything outawhack, and interesting to find situations where 1 isolated panel in the sun is better than 4 combined panels with 3 of them in the sun, but one in partial shade. Clearly the argument for individual panel optimizers.

1624915217928.png

... still gotta figure out if / how I'm going to utilize the Bluetti AC200p in-between power outages. Any ideas?
 
I just got one myself and plan to use my old 2000 watt Honda that still runs great. Plan to charge it with 2 power supply's in 2hrs. Mainly for camping But power out as well. The Honda will use 1 gal of gas at idle every 9 hrs so about 3 to 4 recharges.
 
I just got one myself and plan to use my old 2000 watt Honda that still runs great. Plan to charge it with 2 power supply's in 2hrs. Mainly for camping But power out as well. The Honda will use 1 gal of gas at idle every 9 hrs so about 3 to 4 recharges.
Cool! I've got a new-in-box 1000 watt Firman (cheap from Costco) that I'm hoping to never need to use. LOL! So, you'll do the standard power supply to the regular input, and the other into the solar input... both from the Honda generator?

Are you planning to charge it up every 6 months? That's the big thing I'm wondering about.
 
So, any thoughts on my original question regarding using my Bluetti 200P as my main power supply for my PC to keep the unit constantly charged / topped off?
You might as well put it thru its paces. Its supposed to be for emergencies so if you have quite a bit of experience, know-how and trust, you'll be far more prepared than most.
And it'll be free renewable energy (only the equipment is expensive but energy is free)!

I use my backup battery bank in the garage whenever possible. In the spring it runs the seed incubators and then the greenhouse lights and fans. I have a LOT of experience, know-how and trust. When/if an emergency comes along, it will be ready and i will be prepared.
 
Cool! I've got a new-in-box 1000 watt Firman (cheap from Costco) that I'm hoping to never need to use. LOL! So, you'll do the standard power supply to the regular input, and the other into the solar input... both from the Honda generator?

Are you planning to charge it up every 6 months? That's the big thing I'm wondering about.
Yes both power blocks to the Honda. I read storage at 50% is best.
 
You might as well put it thru its paces. Its supposed to be for emergencies so if you have quite a bit of experience, know-how and trust, you'll be far more prepared than most.
Great point! Now that I've got everything setup (solar panels, connectors / extenders, wire, and the AC200P), it's giving me a good opportunity to test the system outside of an "emergency", so I know I'll be all-set once the time comes :)
 
I read storage at 50% is best.
Ya, that's where I'm confused. Most lithium based battery items say to avoid charging to 100% (like e-vehicles, etc.), but the manual for the Bluetti clearly says to charge to full before storing. Maybe that's less about battery longevity and more about self-discharge issues?
 
We've got some really solid charging going on at 725 watts!!!
1624999073328.png

Now I've got more questions:
  1. Which parts of the AC200P will deteriorate first? The touch screen, inverter, charge controller, batteries, fans, etc?
  2. It seems that I can't turn the unit off while sun is shining / solar input is feeding power... is that really the case? Once plugged into live-solar, there's no way to turn off charging other than doing a DC disconnect "upstream"?
  3. When at 100% charged, can solar be disconnected safely? The panels clearly say NOT to disconnect under load, so if the AC200P is full and no current (or very little) is entering into it, can it be disconnected at the XT90 connector without creating an arc or spark ?
 
I did an experiment in the middle of our "heat dome" 100 deg days. I attached my 2sx2p panels to the AC200P when it was at 100% and cranked up my window AC.

The unit dropped down to 98% and pretty much stayed there with these stats:
1625076873595.png

The fact that the % didn't change makes me think that the difference between 716 w in and 636 w out is ~11% conversion losses?
 
Wont 2x2 of these violate max Isc (12A)?
I'm no expert, so hopefully I'm not blowing anything up :)

2 x 2 of these panels is ~ 74 v (working) and the AC200P limits the input watts to 700w (I've seen it get to 750w), so that's only about 10.2 amps (750 / 74).

If the Bluetti was NOT limiting the input wattage, then my panels (full-sun perfect conditions) would be delivering 360w with 4 panels... or 1,400 watts total at 74v... which would be almost 20 amps!

So, I'm *pretty-sure* I'm not going over 12A with this setup... but I welcome feedback and correction!
 
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Although an electrical engineer, I am new to solar. If you havent seen smoke yet that’s a good sign ( or some solid engineering / safety margins by bluetti).

can anyone with more experience confirm that this setup can produce >20A in short circuit (sunny day yada yada) and may harm the AC200P?
 
@feo here are some posts that help me think that I *might* be ok: (bold is my doing):

700 watts is Max Production not some kind of Max that does damage.
Bluetti does not publish true max over paneling wattages.
I think about 1000 watts of panels should be ok and close to 12A.

However exceeding the 150V max input will stop charging and give an error code that will have to be reset.

AC200 specs are 700w panels and 12A which are not hard maximums.

You can "overpanel" at 4 x 200w = 800w or even use 1000w panels and not damage anything.
Any extra power over 12A will just be clipped or wasted.


The only hard limit is 150V max input But if you exceed you will only get an error code and charging will stop plus you will have to reset the AC200.

2 series 2 parallel means that you connect the plus to minus of 2 panels then do the same to the other 2 panels.
Then connect those 2 sets in parallel by connecting the 2 pluses together and the 2 negatives together with parallel adapters.
2S2P

You can actually over-panel the unit as well, which is a good idea as you'll be able to pull the 700W max for much longer than the peak solar moment and give you the option of running a very small window unit A/C for some hours. As long as you don't exceed the 150V limit on the solar input, it will only take as much as it can up to 700W.


I am thinking of placing 5 Fullriver LiFePO4 12V 22.5 amp battery packs in series, to charge my Bluetti through the solar charging port. This will have the potential to deliver 1,350 watts. Bluetti maxes out at 700 watts for solar input. Does this mean over 700 watts causes a problem or does it mean the Bluetti limits it's intake to 700 watts?
I assume this will not cause any harm?
Thanks. Jay
 
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@feo here are some posts that help me think that I *might* be ok: (bold is my doing):
Nice job digging those up. If the power clipping happens harmlessly, then you may have found a winner, as the 2p configuration should be more resilient to shading.

I’ll still be connecting mine in series tho :). Keep the experiments rolling!
 
You've got me thinking I might do the same since:

1) I don't really need all that "extra" power
2) The "over paneling" only seems to really work if the entire array is in equal sun, and having 4 panels is increasing the likelihood of one of them getting shade, and pulling everything down with it. So, maybe I stick to just a couple panels until I get these on a roof where they won't be getting shaded.
 
The last few days in the SF Bay Area have been really hot, so I did an experiment:
  1. Setup 2 solar panels in series at about 500 - 600 watts (mixed clouds)
  2. Setup a window AC unit in my kid's room... runs at about 650 watts at full-blast
  3. Tied both of the above into the AC200p
It was pretty fun watching the mix of power out and power in, and the fluctuations of supply / demand throughout the day.
 
I did the same last weekend and it was a blast. thanks for paving the way!

the clouds with the panels in series were an issue, (too many failure points) i wish they would come up with something for that?
 
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