I'm surprised this makes sense. When I priced out solar panels and batteries for a similar setup, earlier this year, it was going to take decades just to break even.
Did you look into 12v mini split systems? Avoiding the need for an inverter might drastically bring down costs and efficiency. I’ve seen a couple sets out on the market that come with everything already (prefilled mini split system and solar panels). Adding a transfer switch and an inverter could get you somewhere! I liked the idea of it purely as an “assist” with a larger system. Pull some heat out of the house to reduce the load on the main hvac system.
Ooh, that is really tempting. I'm in Arizona so there should be more than enough sun to go around, and more than enough reason to use it to stay cool without racking up an energy bill.
I visited Phoenix a while ago and I was genuinely surprised by the small amount of houses with rooftop solar. It would truly be a perfect match: lots of sun and lots of air conditioning. But then again, capitalism makes it all so much more complicated.
I’m interested, but what I’m wondering is the power requirements. If I’m remembering the rule of thumb correctly, it takes about 1000 watts to drive a 10k btu ac unit, plus a bit of engineering overhead. 10k btu is fairly modest and will cool about 300-400 sq ft. I’m not sure what a 1000 watt solar setup would look like - my quick search looks like people use a 100 watt setup with relatively portable panel arrays, and use them to charge an external battery which then supports a higher draw, but I imagine it wouldn’t be able to run around the clock or even for extended periods without a big array.
Am I wrong in my reasoning? Sorry, I just have a hard time with videos as opposed to reading.
Nope, you're right. AC uses a lot of power, and 1000W of solar panels would take up at least 5 m2. You would need around double that if you're gonna run solely on solar power, too, as well as a big ass battery bank.
The guy in the video is using a 5000 BTU unit to cool a small room, though, and manually switches to grid power during the night. Would definitely save money.
If I had a house with plenty of space, I would definitely make the investment.
1st: fire hazard, code violations, insurance won’t pay out.
2nd: This is fine for maybe a shed or ADU but when you start doing this to a home and start thinking big picture, there are some questions that come up, such as most of the cost in solar is the labor. If you’re already mounting panels, inverters, wiring, why not go the extra steps to install solar for the home and gain back a lot more costs when the sun is shining? Why mess around with a small window a/c when for the same amount of work (or less) you can install a mini split with better efficiency?
I always think that solar powered AC is one of the most practical ideas out there, and I'm always about practicality first when we're proposing tech solutions to things.