I recently moved back home to CA after spending about a decade in NC, and our new (to us) home came with a 7.2KW Tesla Solar system (installed under the Solar City name). PG&E has been an absolute disaster since we've moved in, so I want to protect ourselves as much as possible from grid failures, and from giving PG&E any more money than we need to.
At the core of this I'd like to add 2-3 PowerWall 2s to the house, and additionally I'd like to add a fair bit more solar. The current solar system appears to be performing within range when I compare it to online production calculators, but it just doesn't keep up with our usage. The house is 3,400sf, has a decent sized pool, above ground spa, 5 ton AC compressor, and two Tesla daily drivers, so I'm not all that surprised. Everything else has been electrically slimmed down as much as possible with gas appliances, LED everything, home automation for power saving, etc.
Right now the things that are confusing me the most are 1) whether to pursue SGIP, and 2) whether to just get a quote from Tesla or consider their licensed installers.
SGIP confuses me, since from what I've read:
1. Tesla no longer has any allocation for SGIP, but their installers may. Although the installers typically end up at a higher price anyway.
2. SGIP mandates 52 discharge cycles per year, which limits the modes you can use on the PowerWalls.
3. Anything over 2 PowerWalls is no longer "small residential" and Tesla won't even help with SGIP on those installations.
4. I'm still unclear on whether the SGIP cycling limit needs to be achieved via solar or grid or both.
So far most of what I'm reading seems to indicate folks are leaning towards sticking with Tesla, and forgoing the SGIP rebate. Curious what everyone thinks about this, since it sort of dictates who I start the quoting/planning process with.
I'm also planning on keeping the pool/spa/cars on the grid side of the gateway, in hope that it would allow me to:
1. Size my self-powering capabilities to include offsetting those large loads.
2. Not have to factor these large loads into battery backup capacity. I'm fine with those loads being dark for a few days if necessary, and keeping a spare backed-up 240V outlet in case I need to charge a car in a pinch.
Is that a fair strategy, or am I overlooking some bit of logic in how the PowerWall decided when to discharge? I saw one YouTube video where the owner showed how Tesla had installed the grid-side CTs beyond the car charging circuits. So the PowerWall knew when they were drawing power and could compensate by discharging, but since the loads were on the grid side of the gateway they wouldn't drain the battery when the grid was down.
Two other less important curiosities:
1. Will Tesla be open to modifying/expanding the current solar system, or will they only design a new system to be installed in parallel?
2. I've seen some rumors of a coming PowerWall 3. Do you think there's any merit in waiting for that to release?
I apologize for the long-winded stream of consciousness, lol. Thank you in advance for any thoughts or insights you might be able to contribute on any of my points above!
At the core of this I'd like to add 2-3 PowerWall 2s to the house, and additionally I'd like to add a fair bit more solar. The current solar system appears to be performing within range when I compare it to online production calculators, but it just doesn't keep up with our usage. The house is 3,400sf, has a decent sized pool, above ground spa, 5 ton AC compressor, and two Tesla daily drivers, so I'm not all that surprised. Everything else has been electrically slimmed down as much as possible with gas appliances, LED everything, home automation for power saving, etc.
Right now the things that are confusing me the most are 1) whether to pursue SGIP, and 2) whether to just get a quote from Tesla or consider their licensed installers.
SGIP confuses me, since from what I've read:
1. Tesla no longer has any allocation for SGIP, but their installers may. Although the installers typically end up at a higher price anyway.
2. SGIP mandates 52 discharge cycles per year, which limits the modes you can use on the PowerWalls.
3. Anything over 2 PowerWalls is no longer "small residential" and Tesla won't even help with SGIP on those installations.
4. I'm still unclear on whether the SGIP cycling limit needs to be achieved via solar or grid or both.
So far most of what I'm reading seems to indicate folks are leaning towards sticking with Tesla, and forgoing the SGIP rebate. Curious what everyone thinks about this, since it sort of dictates who I start the quoting/planning process with.
I'm also planning on keeping the pool/spa/cars on the grid side of the gateway, in hope that it would allow me to:
1. Size my self-powering capabilities to include offsetting those large loads.
2. Not have to factor these large loads into battery backup capacity. I'm fine with those loads being dark for a few days if necessary, and keeping a spare backed-up 240V outlet in case I need to charge a car in a pinch.
Is that a fair strategy, or am I overlooking some bit of logic in how the PowerWall decided when to discharge? I saw one YouTube video where the owner showed how Tesla had installed the grid-side CTs beyond the car charging circuits. So the PowerWall knew when they were drawing power and could compensate by discharging, but since the loads were on the grid side of the gateway they wouldn't drain the battery when the grid was down.
Two other less important curiosities:
1. Will Tesla be open to modifying/expanding the current solar system, or will they only design a new system to be installed in parallel?
2. I've seen some rumors of a coming PowerWall 3. Do you think there's any merit in waiting for that to release?
I apologize for the long-winded stream of consciousness, lol. Thank you in advance for any thoughts or insights you might be able to contribute on any of my points above!
