Air conditioner running on battery

[Allen_C]

24v panels gives you less voltage drop going to the charge controller, as you stated. The charge controller converts down to 12v to charge the battery. Seamless process!

To really run an AC off batteries, you need at least 800Ah of Lithium. My purpose was to see if I could do it and if so, provide an hour or two of constant AC to cool down the inside on the hottest days. Without running the AC we can last about 5 days of regular usage but as you said, the grey tank needs emptied in about 4!

[pconroy]

I agree that it was a fun experiment! I too have more than my fair share of fun-stuff in our RV.


Our 31FK is the same size and one AC isn't enough; we'd need to power two. So a generator is our only pragmatic approach. Still, it was a neat post - thank you for sharing!

[IamSpartacus]

Thanks for the response! 800ah.... I need to win the lottery....

[mtjag7]

Originally Posted by PPOSS

Those batteries are $1000 each, one could run the A/C for an hour continuously, four could make it through the night with ease. But four LifePo4 batteries cost $4,000. Plus $1,250 for the inventor and another $1000 for panels and smart solar charger is still not an affordable way of doing this yet. I can run my $700 inventor generator all night for less than $5.

You can find some pretty good 12v 100ah LiFePO4 batteries on Amazon for about $350 each and a 3000watt inverter for less than $700. So, prices are coming down for sure. The issue we have is our Jayco 199MBS is small and short or storage space to begin with...that and the cost of going full solar as you know. Where as you can buy a 3500watt dual fuel generator for less than $800 now. More noise, less cost.

[Jerry713]

Originally Posted by Allen_C

Yeah, you would need 1000Ah of batteries and a roof full of panels to generate enough solar amps too keep the battery from fully discharging!

Like this guy
https://youtu.be/OszJ3DKokow

[ependydad]

Originally Posted by IamSpartacus

Thanks for the response! 800ah.... I need to win the lottery....

Since someone else resurrected this thread, I’ll respond to this one.

DIY lithium cells aren’t that terrifically expensive and you can build an 800 ah battery bank for not a ton of money. Way cheaper than you can buy one, typically. Even with the cost of the cells, wiring, and BMS.

It was actually a lot of fun doing it.