Without a significant need for backup power and without SGIP rebate, I would not get a Powerwall today. I got them because I got in on SGIP Step 1 and I was already planning to spend money for a nat-gas backup generator. The State will finish the current round of SGIP rebates and then formulate another round since the Governor already signed an extension. It will just take a year or two to get a new program started up again.
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Powerwall 2 - How large of the PV system do I need to charge it? Are they in stock now?
- Thread starter who177e
- Start date
@miimura,
I am quite happy with the performance of my PW2 in the Balanced TBC mode, but I don't understand the cost information I get from looking at my PG&E Energy Use Details/Energy Costs/Day View page. If I look a the "cost" of putting energy to the grid during peak times and divide the "cost" by the kWh, I get $0.267/kWh, no where near the $0.48/kWh I would expect. Even subtracting what I understand the NBCs to be does not come close. Likewise if I look at the off peak times when I am charging our Teslas, I get $0.06/kWh. Why are these numbers so much less than the rates quoted in the tariff schedules?
I am quite happy with the performance of my PW2 in the Balanced TBC mode, but I don't understand the cost information I get from looking at my PG&E Energy Use Details/Energy Costs/Day View page. If I look a the "cost" of putting energy to the grid during peak times and divide the "cost" by the kWh, I get $0.267/kWh, no where near the $0.48/kWh I would expect. Even subtracting what I understand the NBCs to be does not come close. Likewise if I look at the off peak times when I am charging our Teslas, I get $0.06/kWh. Why are these numbers so much less than the rates quoted in the tariff schedules?
I see what you are talking about. The $/kWh I get from a bar in the chart is about half what it should be. I have no idea why the data on that page is like that. You really have to look at the bill to see what's going on. The problem is that the PG&E Powerwall billing is such a mess - even more so because I'm in a CCA. Have you looked at your bill?
For the benefit of others, this is what we're talking about.
Not that I know of. As I understand it, the next steps are getting the County to inspect and then finishing the SGIP application stuff with PG&E, which requires the County inspection. The SGIP was approved some time ago and we have till January to get it working. Almost took that long! At some point, perhaps with the PTO, they will reset my true up date and change the billing. I am obviously operating at this point, but perhaps not officially. I am assuming that my local installer is on top of all this, and I am pretty sure he and his team are.
That's right. After all your permits have final signatures, it goes to PG&E for PTO. They may inspect it also. Then they will close out your existing true-up and start a new one on NEMMT, which is the really strange billing. It's back to the black and white bill like they used to do for NEM, but it's broken down into each and every unbundled rate component and your consumption kWh and export kWh is separately tracked. After PTO, then the SGIP can proceed too.
invalid
Member
I hadn’t realized a Powerwall will move you into yet another new billing structure (NEMMT).
I wonder if life is just easier to go off-grid and solely use the grid hook up for charging cars, since likely hard to beat the price and capacity.
I wonder if life is just easier to go off-grid and solely use the grid hook up for charging cars, since likely hard to beat the price and capacity.
I didn't know it was going to be a different billing either. The billing result is the same as before Powerwall, but for some crazy reason they want to explicitly track your consumption and your export separately in a different billing system. BTW, I'm not saying that your bill will be the same before and after Powerwall installation, I'm saying that the bill calculation for the same net kWh figures in Peak, Part-Peak and Off-Peak would be the same on NEM or NEMMT because it's just the OAR (otherwise applicable rate) like EV-A that determines your bill.
The only way to make the interconnect and billing more simple is if you have a off-grid system that cannot feed back into the grid. For most people, that is not a wise economic choice.
Jigglypuff
Member
There is actually no difference. The utility is just tracking your data differently when you have a Powerwall on NEMMT. The big difference is whether you got solar on the NEM1 tariff or the NEM2 tariff. NEM 2.0 has Non-Bypassable Charges while NEM 1.0 is straight 1:1 retail credit for every kWh exported.
