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If you have solar and a powerwall 2....

If you have solar and a powerwall 2....

Let's say your system is up and running then the power goes out. The fridge and a few other things stay on through the night. But the wall reaches 0% before the sun rises. Now the question is would the solar recharge the battery and you would have power again? Or once it's depleted, you sol?

cwied | 18 april 2018

I don't think anyone knows for sure, but indications are that you can't cold-start a powerwall. The way you would avoid this is to flip all your circuit breakers when you realize the powerwall is going to run out before the sun comes up and only add loads back when solar is producing again.

acegreat1 | 19 april 2018

Someone test it and put in on YouTube. I'll post it when I get it installed but it might be a couple months from now

FloridaDave | 20 april 2018

@acegreat1 I have solar and 2 powerwall 2's. I have it set to full self powered. So my house runs completely off the batteries at night until the batteries are exhausted and it automatically switches back to grid power. The batteries have a builtin untouchable reserve of 0.5kWh in them that can't be accessed by the user. There is a usable capacity of 13.5kWh and total capacity of 14kWh. that .5kWh will keep the system alive in hibernation mode until the solar wakes it up the following morning. Once the solar starts producing again it will first start supplying power to the house on once it is producing more than the house needs it will start charging the battery.

cwied | 20 april 2018

That works when the grid is up, but when the grid is down, the solar won't start producing unless the powerwall provides it a signal to synchronize to. The powerwall can't do this if it's empty and there is no grid. By flipping the circuit breakers you make sure there is still power in the circuit, but no load to drain the storage. That way the powerwall keeps the circuit energized and the solar inverter will start producing when the sun comes up.

Tesla-David | 21 april 2018

@FloridaDave, I am waiting to get my design/plan for my two PW2 installation (hopefully within next couple of weeks)with an existing 13.2 kWh solar system, and am keenly interested in talking to someone with an operational PW2 system such as yours, particularly how well it is working for your home, but also to charge EVs. I have MS and M3 and want to use my PW2 to augment our existing solar system, which produced enough electricity last year, 182 percent to address both our home and EV charging needs for the entire year. I only found one link on Utube from Australia, where this is discussed. Can you comment on your experience with the EV charging component of your PW2 system?

https://www.youtube.com/watch?v=nWLzlrGGuxQ

Marleenyuli | 7 maj 2018

Draining 10Kw overnight on backup is crazy high---but say it's true....once the sun rises it'll start pumping into the PW up to 2kwH charging and then the house/grid after that if you're on the standard program. for Time shifting one should be able to go to house direct, but we don't have that progamming to try out yet. (eagerly awaiting).