I finally decided to get a Powerwall after the recent power outage. We had a generator for the fridge and freezer so everything turned out ok, but with a newborn and a 3-year old, the stress of losing power was too great. Tesla gave me a quote for 2 Powerwalls at $18,305 and one at $11,704 before ITC, and I intend to sign the contract ASAP so I can still claim the 30% ITC.
We have a 3.25kW PV system on EV-A rate and generates on average 14kW per day. About 60 days out of a year it generates more than 20kW. EVs are on a separate EV-B meter.
Currently we're at -646kW with PG&E, and my estimate is at TrueUp we'll be at about -300kW. We get our power from Peninsula Clean Power and they cash me out every year at the actual rate + 1cent bonus per kW.
If we lose power, in a worse case scenario we'll be using 9kW a day if we don't conserve at all. If I factor in 50% growth for the future, it will be 13kW. If we aggressively conserve we can bring it down to 6kW/9kW.
My questions:
1. Since we're already producing more than we use, is one Powerwall sufficient in our case?
2. If I set the Powerwall to "Load Shift" mode, I assume the Powerwall will charge using off-peak/partial-peak rates and discharge during peak-hour rates, so the amount of power sent to the grid should be similar, but more of them will be at the peak-hour rate. Is this correct?
3. If I get two Powerwalls, will the system be smart enough to charge the Powerwalls over several days?
4. Any reason I should get two Powerwalls in my scenario?
Thanks
We have a 3.25kW PV system on EV-A rate and generates on average 14kW per day. About 60 days out of a year it generates more than 20kW. EVs are on a separate EV-B meter.
Currently we're at -646kW with PG&E, and my estimate is at TrueUp we'll be at about -300kW. We get our power from Peninsula Clean Power and they cash me out every year at the actual rate + 1cent bonus per kW.
If we lose power, in a worse case scenario we'll be using 9kW a day if we don't conserve at all. If I factor in 50% growth for the future, it will be 13kW. If we aggressively conserve we can bring it down to 6kW/9kW.
My questions:
1. Since we're already producing more than we use, is one Powerwall sufficient in our case?
2. If I set the Powerwall to "Load Shift" mode, I assume the Powerwall will charge using off-peak/partial-peak rates and discharge during peak-hour rates, so the amount of power sent to the grid should be similar, but more of them will be at the peak-hour rate. Is this correct?
3. If I get two Powerwalls, will the system be smart enough to charge the Powerwalls over several days?
4. Any reason I should get two Powerwalls in my scenario?
Thanks