Educate me... when the power goes out how long does this setup power the house and will it power everything?
I intentionally got enough power walls to power everything, A.C. and electric dryer. After I ordered they did bump the stats so I could have gotten fewer and just had less run time. Rough math, I have more powerwall than my house can possibly pull. I have a 100A circuit, and it looks like latest specs have them doing a combined 175A continuous. Looks like the new stats also say they can do 118A LRA start, so technically now just one could start my A.C and run all my loads. If you never go above 14kW continuous, 2 powerwalls could backup a 200A panel. 4 powerwalls would be capable of putting out enough juice continuous that you would trip the main 200A breaker before you stressed them.
For how long, depends on usage... Each one has 13.5kWh of power. Assuming the inverters are perfect, which they are not, that is 40.5kWh meaning 1,000w for 40.5 hours. That is assuming zero sun. When ordering I looked over all my electric bills from last summer, found the highest use one, then the highest use day, and got enough storage to run everything for at least 12 hours. Since most of that is during the day and would be a full sun day, I should get enough juice during the day to refill the batteries and last the night. I also picked the amount of panels to get close to covering my highest use day. I can't run the solar yet as I need permission to back feed the grid, but the installers did some tests and I was getting ~1-4kW with 100% cloud coverage. It will be interesting to get real world numbers, but I should be close to indefinite run time barring bad weather days.