danrjones said:
That's $444++ per KWh. Not quite the $100 we all dream of, yet.
It is still expensive, but perhaps not as much as first blush suggests
I think the powerwall is good for a lifetime of 10 years full operation equivalent, so
365 days a year
1 kWh a day
10 years
= 3650 kWh. At a cost of 44,400 cents, that is 44,400/3650 = 12.1 cents a kWh
If you cycle to 70% DoD my WAG is a halving of degradation rate. That would extend the lifetime and financing costs but it would also reduce the straight per kWh cost by 1.4x to 12.1/1.4 = 8.6 cents a kWh. For people who do not have the opportunity to charge during the daytime when the PV is producing, that is still cheaper than dirty night time electricity from the grid.
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Absolutely, get more PV !
You will always find a use for PV generation during the day: heat or cool your house, heat up the hot water tank, charge your EV, use appliances ...
Or just hit your utility for high daytime NEM rates ;-)
Do keep in mind though that CA is moving peak hours to later in the day, so west facing PV will be more valuable as a NEM product