Anyone with 12v Air Conditioning Experience?

adamis wrote:

valhalla360 wrote:
500amp-hr at 12v battery bank is about 6kwh. Probably 5kwh usable with lithium.

The air/con you listed is just shy of 1500w when running. Your 5kwh of usable power gives you 3.3hr of run time.

500w of solar will only recharge about 2kwh per day, so 1.3hr unless you run the generator to recharge the batteries.

Not really any better than a stock 15k btu 120v air/con but only 12k btu so it will have to run longer consuming more power.

I don't think these calculations are representative of normal use, at least for the West Coast where I live. Here we tend to get cool nights in the 60s and hot days in the mid to high 90s. The Bigfoot camper is insulated pretty well so it tends to stay pretty cool inside until around noon at which point it has reached the 80s. I am also not intending to run the AC all day, just when I need it which generally would be for meals and possibly to cool things down prior to bed time when the camper walls are still heat soaked and so tend to keep interior warmer than outside.

The second part is that your back of the envelope calculations assume the compressor will be running at max current draw the entire time but that doesn't happen. In my experience it is about a 50% duty cycle and the draw when the compressor isn't running is just a few hundred watts for the fan. You also used the worst case scenario of 120A for the Max Cooling but the website states:

Eco Mode should be the default operation type on a Nomadic Cooling air conditioner. Powerful mode should only be used for short periods of time for maximum cooling, as powerful mode has increased consumption of energy.

Eco Mode consumes 35A to 55A according to the manufacturer. So using the 55A just for simplicity, that is 660 watts of draw and with a 5kwh of usable power, that is 7.57 hours of run time. That assumes the compressor is running 100% of the time but it doesn't because the compressor won't be running the entire time in eco mode. This doesn't even take into account 400w to 600w of solar that could be reducing the battery consumption even further.

For West Coast environment, these numbers would be more than sufficient. Maybe not for the South where AC runs essentially non-stop but then I don't think I would visit the South in the middle of the Summer if I didn't have to.

This all sounds like a very expensive, complicated solution to fix what is essentially not a problem. Find places to camp that wont kick you out for running a generator...
He!!, I'd quit camping before I'd drop $9k (+ more $ solar + a bunch of extra work) to "upgrade" a camper that has a perfectly good AC and power source already.