Charging Powerwalls from secondary solar system?

[bayareaever]

I’m in the process of considering install of Tesla solar with 2-3 Powerwalls. I already have a non-Tesla solar system so the new system would be the second. The existing system has micro-inverters and everything would be feeding to the same breaker panel.

I don’t have the design from Tesla yet but a phone rep told me the second system would not be wired to charge the PWs or be active during grid outages. He said it is a PW warranty issue and not so much a technical one (from what I understood).

I certainly hope he’s wrong although it wouldn’t be a deal-breaker because the new system would have a much higher kw rating than the old one.

Has anyone run into a similar situation and if so, what was the final resolution?

 

[power.saver]

What are the sizes of your existing and new solar systems?

Typically, not more than 5kW of solar is connected per PW. So for 2 PWs 10kW total, and 3 PWs 15kW total. If you exceed that, one will be located outside the backup circuit.

 

[miimura]

This is nonsense. I have a Enphase system from 2012 and it was moved to the Backup side of the Tesla Gateway. It works fine during outages. The only time you won't have all the solar working during an outage is if it's too big for the PWs to absorb. For example, more than 7kW DC solar per Powerwall. In that case, you will undoubtedly have more than one inverter and one or more will be on the grid side of the Gateway so you only have partial solar power during an outage.

 

[bayareaever]

This is nonsense. I have a Enphase system from 2012 and it was moved to the Backup side of the Tesla Gateway. It works fine during outages. The only time you won't have all the solar working during an outage is if it's too big for the PWs to absorb. For example, more than 7kW DC solar per Powerwall. In that case, you will undoubtedly have more than one inverter and one or more will be on the grid side of the Gateway so you only have partial solar power during an outage.

Good to know, that’s what I was hoping to hear. I’m quite sure there’s no technical limitation here because both solar systems combined will not even nearly exceed 15 or even 10 kw output (2kw old system+ 4-8 kw for new one).

The phone rep said that charging pw from 3rd party solar will void pw warranty because if something malfunctions, they won’t know who to blame. Hopefully they didn’t add that to pw warranty restrictions recently.

 

[bayareaever]

This is nonsense. I have a Enphase system from 2012 and it was moved to the Backup side of the Tesla Gateway. It works fine during outages. The only time you won't have all the solar working during an outage is if it's too big for the PWs to absorb. For example, more than 7kW DC solar per Powerwall. In that case, you will undoubtedly have more than one inverter and one or more will be on the grid side of the Gateway so you only have partial solar power during an outage.

Is the the ‘12 Enphase system Tesla or non-Tesla?

 

[getakey]

I added PWs to non-Tesla solar. No warranty restrictions

 

[bayareaever]

I added PWs to non-Tesla solar. No warranty restrictions

Did Tesla do the PW install or a 3rd party?

 

[miimura]

Is the the ‘12 Enphase system Tesla or non-Tesla?

Solar City and Tesla don't install Enphase. Period.