danrjones wrote: ↑
Wed Aug 12, 2020 7:28 am
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
= 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.
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