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Curious about SPS + A/C. Due to a medical condition in my household, having A/C even during an extended power outage would make life a lot easier.

toomuchtodo 8y ago
Highly recommend Outback or SolarEdge inverters, but based on your AC load, you are going to need a sizable battery. Tesla’s Powerwall isn’t the only solution (LG Chem has one as well), and as long as the battery is only ever charged from solar (not the utility, it’s an inverted setting), it’ll qualify for the 30% federal tax credit along with the rest of your rooftop solar install. Depending on your state and utility, there may be even more incentives available beyond the 30% federal tax credit.
- sathackr 8y ago
  +1 to SolarEdge. I have an HD Wave and it seems to be a really nice inverter. They have some nice ones that can connect to a battery as well.
rbritton 8y ago
Air conditioning is incredibly power-hungry when powered from an inverter. My solar experience is with an RV, but even with that lower-powered AC unit, you can realistically expect only 30-60 minutes with the batteries an RV can carry. A house won’t have the same space or weight restrictions, but that doesn’t make them any cheaper. FLA batteries are the least expensive currently available, and I’d ballpark it at around $4000 in batteries alone to get a few hours of air conditioner.
- coding123 8y ago
  An alternative to this is to have a generator that works with either propane or car-gas.
- bonzini 8y ago
  Are those lead batteries or lithium? A lithium battery pack is about 10 times lighter, and 2-3 times smaller, than a lead battery pack that can store the same energy.
cbr 8y ago
> Curious about SPS + A/C The SPS is rated for 2000W, best-effort. That gets you probably one large window AC. It will run when the grid is down and the sun is shining on your panels, which depending on how your roof is angled and what trees etc there are might or might not be enough? It will have times when it loses power due to clouds. I believe when that happens the SPS turns itself off and you need to manually re-enable it by flipping a switch in the basement. So might be a lot of hassle.

toomuchtodo 8y ago

Highly recommend Outback or SolarEdge inverters, but based on your AC load, you are going to need a sizable battery. Tesla’s Powerwall isn’t the only solution (LG Chem has one as well), and as long as the battery is only ever charged from solar (not the utility, it’s an inverted setting), it’ll qualify for the 30% federal tax credit along with the rest of your rooftop solar install. Depending on your state and utility, there may be even more incentives available beyond the 30% federal tax credit.

sathackr 8y ago
+1 to SolarEdge. I have an HD Wave and it seems to be a really nice inverter. They have some nice ones that can connect to a battery as well.

rbritton 8y ago

Air conditioning is incredibly power-hungry when powered from an inverter. My solar experience is with an RV, but even with that lower-powered AC unit, you can realistically expect only 30-60 minutes with the batteries an RV can carry. A house won’t have the same space or weight restrictions, but that doesn’t make them any cheaper. FLA batteries are the least expensive currently available, and I’d ballpark it at around $4000 in batteries alone to get a few hours of air conditioner.

coding123 8y ago
An alternative to this is to have a generator that works with either propane or car-gas.
bonzini 8y ago
Are those lead batteries or lithium? A lithium battery pack is about 10 times lighter, and 2-3 times smaller, than a lead battery pack that can store the same energy.

cbr 8y ago

> Curious about SPS + A/C The SPS is rated for 2000W, best-effort. That gets you probably one large window AC. It will run when the grid is down and the sun is shining on your panels, which depending on how your roof is angled and what trees etc there are might or might not be enough? It will have times when it loses power due to clouds. I believe when that happens the SPS turns itself off and you need to manually re-enable it by flipping a switch in the basement. So might be a lot of hassle.