Off grid air conditioning test, SOK battery response

[SupraSPL]

My 8K Midea used 3kwh to keep a 150 sq ft room at 68F for 24 hours during a 93F day.

 

[Bluedog225]

edit-delete

 

[Vigo]

The 8k i was referring to is the Midea. I bought mine for $350 new in early June i think, but they've come down some since. Costco sells a 12k version without the U-channel for the window to drop into for $280 i believe, plus it has 'supplemental heat'. Im actually planning to go get one and move my existing one somewhere else.

 

[Pelageo]

So I went through the exercise of charging the 2 12V SOK batteries separately and then in series to full charge. I checked the batteries individually on several occasions throughout the test period and found that the voltage was equal on both batteries. Turns out if there is no power coming into the charge controller, the BMS will shut off one of the batteries somewhere around 11.5-11.8V. If there is as little as 5 watts coming from the panels, the battery will stay on and discharge to the speced 10.4V BMS shutdown voltage. When there was no solar power, either battery was subject to shut off. So I guess the batteries are fine and the BMS needs external power to operate below ~11.5V.

Other beginner revelations:

• I think the minimalist key to surviving extreme heat off grid is panel capacity.
• A regularly priced $240 POS (GE 6000BTU air conditioner) is still a POS at $200.

 

[Vigo]

Nice! Aways good to get resolution on a forum thread.

Bot sure what you mean about the ac being a pos? Did it break?

When i went off grid in Texas in May i went ‘big’ on panels (10kw) and now i wish id gone bigger. Well, i have even more to install, i just wish id bought more MATCHING panels from Santan before they ran out. ? I will eventually overpanel my 2x growatt spf5000s up to around 20kw and probably have another 7k or so hooked to other things. Not having AC is NOT an option!!

 

[Pelageo]

Nice! Aways good to get resolution on a forum thread.

Bot sure what you mean about the ac being a pos? Did it break?

When i went off grid in Texas in May i went ‘big’ on panels (10kw) and now i wish id gone bigger. Well, i have even more to install, i just wish id bought more MATCHING panels from Santan before they ran out. ? I will eventually overpanel my 2x growatt spf5000s up to around 20kw and probably have another 7k or so hooked to other things. Not having AC is NOT an option!!

In fairness to GE, the unit did blow cold air, you just have no control over where. From my chosen window in the middle of a wall, it blows dead left to a vacant corner, the sliding fin adjustment on the front just for decoration I suppose. It doesn't cool any size space at 105 deg so direction is critical to get any benefit from the watts and noise.

 

[Vigo]

Ok, i see what you mean. Window units have dicharge vent designs which range from pretty good to completely terrible, and that’s before you even consider that they discharge cold sinking air.. directly above their intakes. ?

Having said that i dont have any continuous spaces large enough that window units dont work well in them. Its just they would all be better if they were through-wall mounted higher up the walls, but i haven’t bothered with that yet.