My Nissan Leaf Forum

Randy wrote: ↑

Wed Aug 21, 2019 9:19 pm

iPlug wrote: ↑

Wed Aug 21, 2019 6:32 pm

ybitz wrote: ↑

Wed Aug 21, 2019 6:05 pm

doesn't work in CA per Randy, right, since you can't get paid for exporting to the grid from battery?

Not legally. But even if one found a way to still do this, it's a pretty bad idea (economically). PG&E for example, California's largest utility, only pays to the resident ~$0.02-0.03/kWh for electricity net generation.

iPlug,
I can't speak for PG&E, but down here in San Diego you get full retail pricing credit for exported solar energy, based on the pricing plan you're on and at the time of export (if you're on a TOU rate). This policy is good up to the point where your annual generation equals your annual consumption. If you generate above that amount, during your annual true-up you will get the wholesale energy price for all energy ABOVE your annual consumption. So for the bulk of most people's generation, you're getting full retail pricing credit.

Right. That is what I meant by net generation - anything in excess of that is wholesale. Suspect CPUC dictated same terms for all the public utilities in the state.

Net generators or not, with rare exceptions, if one has the roof or other real estate to put up solar PV, ROI is markedly better than a home battery.

iPlug wrote: ↑

Wed Aug 21, 2019 7:24 pm

SageBrush wrote: ↑

Wed Aug 21, 2019 6:56 pm

The idea would be to send e.g. a kWh of PV generation to the grid during peak and then collect ~ 2 or 3 kWh at night from the grid

Would imagine on a hot summer day, after the sun went down, residential AC units still running hard, the utility would likely be interested to buy residential battery stored electricity above wholesale rates, maybe at something like $0.10-20/kWh (or whatever spot price is at the moment) then turn around and sell it to ones neighbor at $0.467/kWh (current max rate on my plan).

You make fine sense but I don't think that is what SDG&E allows. In fact, they are so keen to prevent arbitrage of the grid supplied energy that I have read that Tesla (and presumably other battery storage vendors) are forced to program the battery electronics in a fashion that precludes battery -> grid.

Utilities suck eggs, no two ways about it.

iPlug wrote: ↑

Wed Aug 21, 2019 7:24 pm

Would imagine on a hot summer day, after the sun went down, residential AC units still running hard, the utility would likely be interested to buy residential battery stored electricity above wholesale rates, maybe at something like $0.10-20/kWh (or whatever spot price is at the moment) then turn around and sell it to ones neighbor at $0.467/kWh (current max rate on my plan).

SageBrush wrote: ↑

Wed Aug 21, 2019 10:00 pm

... don't think that is what SDG&E allows. In fact, they are so keen to prevent arbitrage of the grid supplied energy that I have read that Tesla (and presumably other battery storage vendors) are forced to program the battery electronics in a fashion that precludes battery -> grid...

Yes, was referring to the point that they don't allow it now, but wistfully longing that the future could be different.

From what I had read last year when looking into this for our home, I think it was the CPUC with the California Self-Generation Incentive Program (SGIP) that was the main barrier; per the Powerwall website:

"The goal of the SGIP program is to reduce load on the grid and reduce greenhouse gas usage. In order to participate in the program, SGIP requires you to use Powerwall to help the program meet this goal. Powerwall must meet a ‘cycling’ requirement where Powerwall will need to fully charge and discharge at least 52 times, or 687 kWh, per year.

Tesla has designed Powerwall to comply with these requirements with little impact to customers."

Could be that this is mostly to avoid allowing the use of the battery primarily as a standby backup. Not sure. Of course the utilities would be more than fine with paying nil for any power from the customer if the regulators granted them such. That remains almost the case for net generation here.

SageBrush wrote: ↑

Wed Aug 21, 2019 10:00 pm

iPlug wrote: ↑

Wed Aug 21, 2019 7:24 pm

SageBrush wrote: ↑

Wed Aug 21, 2019 6:56 pm

The idea would be to send e.g. a kWh of PV generation to the grid during peak and then collect ~ 2 or 3 kWh at night from the grid

Would imagine on a hot summer day, after the sun went down, residential AC units still running hard, the utility would likely be interested to buy residential battery stored electricity above wholesale rates, maybe at something like $0.10-20/kWh (or whatever spot price is at the moment) then turn around and sell it to ones neighbor at $0.467/kWh (current max rate on my plan).

You make fine sense but I don't think that is what SDG&E allows. In fact, they are so keen to prevent arbitrage of the grid supplied energy that I have read that Tesla (and presumably other battery storage vendors) are forced to program the battery electronics in a fashion that precludes battery -> grid.

Utilities suck eggs, no two ways about it.

fyi, SDG&E doesn't set the rules that prevent this.

Randy wrote: ↑

Thu Aug 22, 2019 6:58 am

fyi, SDG&E doesn't set the rules that prevent this.

Are you saying they did not lobby for or help propose those rules?

davewill wrote: ↑

Thu Aug 22, 2019 10:01 am

Randy wrote: ↑

Thu Aug 22, 2019 6:58 am

fyi, SDG&E doesn't set the rules that prevent this.

Are you saying they did not lobby for or help propose those rules?

Exactly.

Utilities lobby/bribe/politic their regulatory commission to accept the shit they want and then consumers are told it is the will of the commission. SUCH bullshit