Skryll
Active Member
I don't know if you've had anyone out to your house yet or not but what I was told by the people that I had come out was that basically 1 Powerwall can be a whole house back up as long as you don't have any breakers that are greater than 30A. If you do then you need an isolated (critical) panel installed in which they can basically move everything that is under 30A over to it. In my case everything would be moved except for 1 electric oven, 240v EVSE, and my A/C. If you have 2 Powerwalls though everything up to 60A (??) can be backed up. The issue is that the Powerwall can't continuously output more than 5kWh so anything over 30A could consume more. My EV can only pull 3.3kWh right now but as it's on a 50A breaker it couldn't be backed up if I were to go with 1 Powerwall.
I got a quote for two powerwalls to back the 200A main. For some reason they want to 'upgrade' our 200A main panel for an additional $6k, which would push the amortization past the warranty.
We currently have two sub panels attached to that 200A main, and since 2015 are backfeeding the 10kW solar through the same sub panel we have the EV chargers and AC on, while the rest of the home is on the other.
They basically said they need to fit the powerwall inbetween the main and the two sub panels but for some reason they think that costs $6k, because of all the equipment needed, which I find hard to believe. I am pushing back at them to see if they can figure something better out. An alternative would be to just have a partial backup for the solar/EV charger/AC sub panel, but I am not really interested in that solution.
The single powerwall solution would have an install cost of $1950, the predicted range is $800 to $2000, so maybe they think because I own a tesla I need to pay top of the range?
I am definitely not going to pay $20k to get two powerwalls. And who knows if the SGIP will come to help offset that.
Powerwall 2 installation: Costs and CA SGIP rebate | Tesla mentions somebody that got a free rewiring to the main. So why does it cost $6k in my case.