MySuperDikeyDayJob
New Member
I'm building an off-grid hut in the back yard, it's 8x10x12 high. I purchased a 4Patriots "1800" which has a max capacity of 768 DC Watt-hours or 690 AC Watt-hours from full battery to dry. But... I can't find a small enough window A/C or mini-split to run off battery overnight. Recharging the batteries isn't the mathematical problem; presuming 2x100W solar panels (I can add up to 2 more on this solar generator) will power everything while the sun shines. Limiting factor is when the panels stop producing energy, I have max 690 WH to keep me cool overnight (and, possibly, hopefully, keep my food cool but that's a different math problem.) The smallest EnergyStar A/Cs I've found rated 4000 BTU run at around 400W so in theory i get less than 2 hours cooling then sweat the next 12 hours. Since i live in the deep south and hurricanes (i.e. power out) come with the hottest of the weather, I really do need A/C even if not cold.
Some assumptions I am challenging:
1. That an A/C rated at 400-watt is assumed to run 100% of the time. Yes? then with generous (warm) thermostat I might only draw say 25% of the power? If that is the case then I would be theoretically running an average of 100 watts/hr then i might get 6.9 hours of cooling
2. Are there smaller A/Cs out there, with lower Watt draw, preferably mini-split? if so please advise because I'm still looking. Are there DC Air/Cons?
3. Do i really have to spend another $2k on a second generator just to stretch from 2-hours to 4-hours of overnight cooling?
I find it hard to believe i'm the only one with this problem, or maybe i just need to buck up and double my system?
All constructive ideas are welcome, as well as mathematical explanations if I'm calculating things wrong. Product recommendations most welcome.
Thanks! KC
Some assumptions I am challenging:
1. That an A/C rated at 400-watt is assumed to run 100% of the time. Yes? then with generous (warm) thermostat I might only draw say 25% of the power? If that is the case then I would be theoretically running an average of 100 watts/hr then i might get 6.9 hours of cooling
2. Are there smaller A/Cs out there, with lower Watt draw, preferably mini-split? if so please advise because I'm still looking. Are there DC Air/Cons?
3. Do i really have to spend another $2k on a second generator just to stretch from 2-hours to 4-hours of overnight cooling?
I find it hard to believe i'm the only one with this problem, or maybe i just need to buck up and double my system?
All constructive ideas are welcome, as well as mathematical explanations if I'm calculating things wrong. Product recommendations most welcome.
Thanks! KC