Solar air conditioning and boondocking

Most people think that boondocking at high altitude means there is never a need of air conditioning. Let me tell you that when there is a heat wave it gets hot, even up there. The records are in the 90's and a RV sitting in the sun is a easy bake oven. We used a Champion 3500/4000 watt generator the first year, trying to run the air and converter for charging at the same time was too much for the Champ. Turning off the converter makes running the air easier but it is still a heavy load as the generator losses up to 40% at 10,000 ft. It is also loud, smells and guzzles gas, not what you think of for the scenic boondocking spot.

When I decided to upgrade the solar from two Bosch 245w mono panels that would take a dive in overcast conditions to polys panels, I also decided to go with three instead of two. The reason was simple, I wanted air conditioning without having to have the generator along.

750w of solar flat mounted has the ability to run a Frigidaire 5000 BTU energy star rated window air conditioner that pulls 450w once the pressure is up. It can only do it when peak sun is out but that's when we need the A/C the most. Having it be only 450w is easier on the batteries in overcast conditions when the solar has reduced output.

The inverter pulls 33-38a  while the compressor runs, the solar has the ability to run up to 45a.

My first test were here at home with the panels in the drive. using a old 8-D starting battery that couldn't start the A/C on it's own, I've run it with the solar from 10 am to past 3 pm. Past then the light is low enough that the panels start losing output and the batteries voltage slips ever so slowly. Even the old 8-D ran it for hours with the solar before dropping to 12v under load. That is without letting the compressor cycle, normally it doesn't run constantly.

This is the driveway test of the air conditioner in the trailer on a 95 f day. I had it in the back bunk window and that worked against it by restricting the air flow too much. Even then it was able to keep our poorly insulated trailer sitting in the sun down to 80-81 degrees. That doesn't sound great but sitting in the sun like that the trailer would have been on its way to 120 degrees without the air conditioner.

While camping we put in the front bedroom window and it did a lot better as the air flow wasn't restricted. A remote lets us switch to fan only when a brief cloud comes over and keep the bank in float.

The nice thing about having it here is if it did get really hot, we can pull the curtain on the bed and the A/C would cool the bed area really fast for a nap.

I did run the A/C in overcast conditions for three or four hours, it didn't kill our 675 Ah bank. In fact we turned right around and used the cook top pulling 470w to make dinner right after.

So can you have air conditioning while boondocking? YES Like any other load it is a process of balancing all of the factors.

The model of air conditioner is Frigidaire Model: FFRE0533Q1 and we use a Tripp-lite 1250fc industrial inverter to run it. 

Thanks for looking
Jim