Looking at adding non-Tesla batteries to an existing Tesla Solar + Powerwall2 system, which provides whole home backup.
Some reasons:
Some criteria:
(1) "Z" Tesla Gateway Version 1 (200A breaker) is the service entrance after the net meter, feeds, via AWG 1/0 wiring:
(1) "W" Main house panel (225 or 400A bus bar, with 200A circuit breaker)
(1) "Y" Generation Panel (225A Bus bar, 200A circuit breaker)
"Y" Generation panel has:
(1) 60A cicuit for PV 12KW SolarEdge inverter PV
(2) 30A circuits for (2) Tesla Powerwall2
Electric utility powerclerk system shows various EG4 inverters and batteries are approvied if expanding an existing system.
Looking at adding
(1) EG4 12kPV hybrid inverter, model IV-8000-HYB-AW [240V]
(4) EG4-WallMount Indoor Battery WM-48-280-1-IN-LL-00
My thinking is to add a 40AMP circuit to the "Y" Generation panel, wired to the 12kPV inverter "Grid" connection.
Add outdoor 40A+ AC knife disconnect between EG4 inverter and "Y" generation panel.
New EG4 Batteries would be connected to the 12kPV inverter.
The load, generator, and PV inputs of the 12kPV inverter would be unused. So the 12kPV inverter is possibly overkill.
The EG4 inverter could largely be kept "offline", in fact, the AC circuit could be cut most of the time. It's only use would be in cases where the Tesla batteries drop below a certain charge threshold, when no grid power exists. I see the EG4 inverter uses CT probes, though the full possiblities of control/curtailment/etc I'm not currently well versed with.
The tesla gateway would continue to be the brain, and the status of the gateway can be queried in a number of different ways. e.g. even a Raspberry Pi could influence the operating mode of the EG4 inverter.
Anybody with thoughts or experience in this area? Right choice of inverter, what are control options, etc?
Some reasons:
- Powerwall2 Devices are difficult to obtain, particularly for reasonable prices.
- Tesla installers seem to prefer to throw away PW2, favoring complex ($$$) system changes for PW3. PW2 and PW3 don't appear to have interop in mind.
Some criteria:
- Expand existing approved grid connected net metered system.
- Minimize changes to the existing Tesla components of the system.
- Increasing continuous max output wattage of ESS system IS NOT a primary consideration.
- Primary consideration IS increasing the runtime in the event of grid outages.
- Leave some capacity in the generation panel for future expansion, e.g. V2G, etc.
(1) "Z" Tesla Gateway Version 1 (200A breaker) is the service entrance after the net meter, feeds, via AWG 1/0 wiring:
(1) "W" Main house panel (225 or 400A bus bar, with 200A circuit breaker)
(1) "Y" Generation Panel (225A Bus bar, 200A circuit breaker)
"Y" Generation panel has:
(1) 60A cicuit for PV 12KW SolarEdge inverter PV
(2) 30A circuits for (2) Tesla Powerwall2
Electric utility powerclerk system shows various EG4 inverters and batteries are approvied if expanding an existing system.
Looking at adding
(1) EG4 12kPV hybrid inverter, model IV-8000-HYB-AW [240V]
(4) EG4-WallMount Indoor Battery WM-48-280-1-IN-LL-00
My thinking is to add a 40AMP circuit to the "Y" Generation panel, wired to the 12kPV inverter "Grid" connection.
Add outdoor 40A+ AC knife disconnect between EG4 inverter and "Y" generation panel.
New EG4 Batteries would be connected to the 12kPV inverter.
The load, generator, and PV inputs of the 12kPV inverter would be unused. So the 12kPV inverter is possibly overkill.
The EG4 inverter could largely be kept "offline", in fact, the AC circuit could be cut most of the time. It's only use would be in cases where the Tesla batteries drop below a certain charge threshold, when no grid power exists. I see the EG4 inverter uses CT probes, though the full possiblities of control/curtailment/etc I'm not currently well versed with.
The tesla gateway would continue to be the brain, and the status of the gateway can be queried in a number of different ways. e.g. even a Raspberry Pi could influence the operating mode of the EG4 inverter.
Anybody with thoughts or experience in this area? Right choice of inverter, what are control options, etc?
