CPUC NEM 3.0 discussion

[swedge]

batteries are not a viable substitute for a generator.

Perhaps batteries are not a substitute, but batteries are a nice addition to a generator + solar system because they let you use your solar when the grid is down, and even continue using your solar after the sun goes down.

I our case, we had solar during the first few multi day PSPS grid outages. We used a portable 2kW propane powered generator 2 or 3 times a day to make coffee, chill down the fridge, and recharge a small car battery + inverter to keep our internet alive. We even watched a bit of TV. It was sort of like camping, but with extension cords everywhere.

When we got our PW, we decided to hang on to the generator so we could still survive extended outages during short, cloudy winter weather when there would not be enough solar to make it through the nights. That was 2 years ago and we haven't fired up the gen since. It is only a backup to our backup, but still a good idea. And propane doesn't go bad, like gas does.

The economics of batteries are problematic. We got ours essentially free through SGIP, otherwise we'd still be relying on the generator alone.

Vehicle to house would be very nice! As would being able to charge PW with a generator.

SW

 

[fresnoboy]

I had this discussion with a friend who was arguing that PWs would make it where he didn't need a generator. I had to ask, what happens if the outage occurs on a cloudy winter day? What happens if it's smoky and hot, and you're running the HVAC to keep the house cool, and the panels just aren't generating?

Then you get people who argue that a generator connected to natural gas is a viable substitute for an on-site fuel source. They're going to be sorry when an earthquake takes out the natural gas service and they're stuck without electricity for days, and the generator isn't doing anything in the very scenario they bought it for.

The only thing I can think of is that there appears to be a very large percentage of people whose goal is to make it where they don't have to pay anything to PG&E (or at least pay very minimal bills), return on investment be damned. Back when E-1 was the dominant plan and NEM1 was the norm, you'd see people buying enough solar to offset all of their usage, and that never made sense to me. Back then, the best ROI on solar was to get enough of it to knock yourself out of Tier 3 and Tier 4, since you could effectively get electricity from the solar at Tier 3 or Tier 4 rates and decrease the payback time dramatically. Putting enough solar to offset Tier 2 and Tier 1 usage never really made sense. And the economics get even worse when you consider that a lot of people do the calculations such that they figure out how long it would take for the solar/storage to offset an equal amount of PG&E bills, neglecting the fact that had you not gotten solar/storage, you could have invested that money in something else and it would be making money in the meantime.

If you do the calculation for a PW, and look at its capacity and warranty (# of cycles), you'd find that you're paying over 20¢/kWh just to time shift electricity usage, and that doesn't even account for the fact that you don't get 100% of the electricity out of a battery that you put into it. I'm not sure in what world it ever makes sense to pay 20¢/kWh to avoid paying peak rates, even at PG&E prices.

Well, I think solar battery storage is in the news, and even the PUC is talking it up in the NEM 3.0 discussion. Tesla is the leader in battery storage by far, so people must think it makes sense somehow, but the math isn't that complicated. I am a techie, and would love to install Powerwalls, but it's just a poor use of money, and even poorer when higher interest rates raise the cost of capital.

And yes, nat gas regenerators don't make much sense here in earthquake land. But it's made even more a problem by seismic shutoff valves that at least my insurance company wants installed these days. With those you can guarantee the generator will fail in an earthquake, though they can be manually reset. All that is why I bought a diesel generator. Industrial units are available for pretty good prices on ebay, but you need room to install them etc...

In any case a few more episodes like last weekend and folks with powerwalls will figure out Elon wasn't giving them the full story.

 

[sunwarriors]

I had this discussion with a friend who was arguing that PWs would make it where he didn't need a generator. I had to ask, what happens if the outage occurs on a cloudy winter day? What happens if it's smoky and hot, and you're running the HVAC to keep the house cool, and the panels just aren't generating?

Then you get people who argue that a generator connected to natural gas is a viable substitute for an on-site fuel source. They're going to be sorry when an earthquake takes out the natural gas service and they're stuck without electricity for days, and the generator isn't doing anything in the very scenario they bought it for.

The only thing I can think of is that there appears to be a very large percentage of people whose goal is to make it where they don't have to pay anything to PG&E (or at least pay very minimal bills), return on investment be damned. Back when E-1 was the dominant plan and NEM1 was the norm, you'd see people buying enough solar to offset all of their usage, and that never made sense to me. Back then, the best ROI on solar was to get enough of it to knock yourself out of Tier 3 and Tier 4, since you could effectively get electricity from the solar at Tier 3 or Tier 4 rates and decrease the payback time dramatically. Putting enough solar to offset Tier 2 and Tier 1 usage never really made sense. And the economics get even worse when you consider that a lot of people do the calculations such that they figure out how long it would take for the solar/storage to offset an equal amount of PG&E bills, neglecting the fact that had you not gotten solar/storage, you could have invested that money in something else and it would be making money in the meantime.

If you do the calculation for a PW, and look at its capacity and warranty (# of cycles), you'd find that you're paying over 20¢/kWh just to time shift electricity usage, and that doesn't even account for the fact that you don't get 100% of the electricity out of a battery that you put into it. I'm not sure in what world it ever makes sense to pay 20¢/kWh to avoid paying peak rates, even at PG&E prices.

This is why all this is a lot easier if you toss ROI out the window and just assume a few things. IOU energy prices will always keep going up (come on, it's the IOUs). I think San Diego ROI with solar only is like 4-5 years on NEM2.0. I laugh when I see people complain about PG&E rates when we'll be over 70c/kWh this coming summer on peak. I have seen Hawaiian folks complain and post their rates and ours is higher even in winter. On NEM3.0, the credit is only like 13% here. As for over exporting, it's just great to have more when seriously, I don't think all the rich folks here will sweat a few bucks and get a few PWs with all their fancy cars, 8 figure net worth, etc...I haven't paid a power bill with the CA climate credit, all my true-up credits for months and that includes covering all my gas as well. There is something to be said also with PWs giving you more options to sorta tell IOUs to $(#* off.


I'm a huge advocate for maximizing and oversizing solar though. I don't even have enough solar to charge the EV currently. People will continue to use more energy I think moving forward so maximize if someone is thinking of installing IMO. It's too much of a pain to add more later (more IMO).

I'm also not naive to think you can only get PWs and call it a day though. That's just stupid. For me, it's eventually going to possibly be maybe more batteries, V2H option (Enphase says 2024, Emporia says they are looking to do this as well actually in 2023/2024), massive generator, and I think we can go pretty long. Just because you depend on a gas generator and the IOU (with diesel probably as well) doesn't mean it's that bad for that massive earthquake/freeze spell.


A lot of folks harp about ROI, I always say there is little/none with batteries, but sorta like buying fire insurance, having PWs for the cost with all the $$ folks here have seems like a no brainer to me. I'm not anywhere rich and would still dump $$ there honestly and we've never even had a power outage still.

 

[ohmman]

A lot of folks harp about ROI, I always say there is little/none with batteries, but sorta like buying fire insurance, having PWs for the cost with all the $$ folks here have seems like a no brainer to me. I'm not anywhere rich and would still dump $$ there honestly and we've never even had a power outage still.

It's funny how inconsistent we humans are with our financial decisions, isn't it? There is some "insurance" value to whatever each person's perceived risk is. For me, I bought some of the first PW2s as the first part of my installation, and they have acted as perfect "generator replacements" for the last 5+ years. I have avoided any outages, and have never run out of battery power. My PV was always enough to recharge my batteries and keep my house and well alive, because the period of time that we typically have outages here is October during PSPS and Diablo wind events. The sun is typically shining then, and the weather is mild. PSPS weren't even a thing when I had the PWs installed, so I looked pretty good to my family when they started and we had power the whole time. I bought them initially just because we are on a well and outages meant no water.

This doesn't mean that they're a failsafe generator replacement. Obviously if there is a big earthquake event in December when it's cloudy and cold, I'm not going to be living in full comfort. However, that's a risk that I am currently willing to take when I weigh it against the desire to own and maintain another fossil fuel fired device. There is too much unknown there - will roads be passable? Will diesel even be available? If roads are passable, I'll just drive to our second home (speaking of inconsistent financial decisions).

Battery storage works for me. It mitigates the highest frequency power risks (PSPS, wind events), and provides a low maintenance, low carbon alternative to a generator.

 

[sunwarriors]

Just noticed 2023 has new energy rates. Here's the damage for San Diego:

Total Electric Rates | San Diego Gas & Electric

www.sdge.com

Residential:

Time of Use, TOU, Pricing Plans, TOU Pricing Plans | San Diego Gas & Electric

www.sdge.com

TOU-DR-1:
On-Peak Winter is 51.9c/63.6c <130% Baseline/ > 130% Baseline.
On-Peak Summer will be 71.5c/83.3c

EVs:

Electric Vehicle Pricing Plans | San Diego Gas & Electric

www.sdge.com

Summer will be 81.6c on EV-TOU-5.

 

[Redhill_qik]

Just noticed 2023 has new energy rates. Here's the damage for San Diego:

Total Electric Rates | San Diego Gas & Electric

www.sdge.com

Residential:

Time of Use, TOU, Pricing Plans, TOU Pricing Plans | San Diego Gas & Electric

www.sdge.com

TOU-DR-1:
On-Peak Winter is 51.9c/63.6c <130% Baseline/ > 130% Baseline.
On-Peak Summer will be 71.5c/83.3c

EVs:

Electric Vehicle Pricing Plans | San Diego Gas & Electric

www.sdge.com

Summer will be 81.6c on EV-TOU-5.

Wow, that is crazy high. The Super Off-Peak is 15.4C from 12:00-6:00am weekdays and 12:00-2:00pm weekends with Off-Peak of 48.1c.

 

[sunwarriors]

Wow, that is crazy high. The Super Off-Peak is 15.4C from 12:00-6:00am weekdays and 12:00-2:00pm weekends with Off-Peak of 48.1c.

TOU-EV-5 is a popular plan. I was dead set to go on it, but since I net export, decided not to since there is a minimum $16/month on that plan. It's great if you drive a lot and need to charge a lot, but you pay for it if you don't have solar with soon to be 81.6c. Already seeing a lot of TV new stories about power bill increases here.

 

[getakey]

81.6c??? Crazy

PG&E got a rate increase too. I have not looked

 

[miimura]

81.6c??? Crazy

PG&E got a rate increase too. I have not looked

PG&E Tariffs have not been updated yet. EV2 was last updated on September 1, 2022 and E-1 and E-TOU-C were last updated on June 1, 2022.

 

[sunwarriors]

Has anyone done math/thinking on just getting PWs/batteries without solar? I assume no ROI, but grid outage benefits and one can charge up to 100% off-peak from grid by default, use during on-peak daily. Would still be horrible for summer/AC required periods, but I wonder if that's actually a better option if you can take the 30% tax credit from purchase. Of course, just getting under NEM2.0 is ideal, but thinking after NEM3.0 is live.

 

[Redhill_qik]

PG&E Tariffs have not been updated yet. EV2 was last updated on September 1, 2022 and E-1 and E-TOU-C were last updated on June 1, 2022.

The updated tariffs have been published, generation costs are up, but distribution costs are down and the PCIA cost is way down, so there is a weird mix. The E-TOU-C and EV2 rates are lower, but the E-TOU-D rate is higher and the climate credit is also slightly lower for 2023.

All tariffs - Tariffs

 

[Redhill_qik]

Has anyone done math/thinking on just getting PWs/batteries without solar? I assume no ROI, but grid outage benefits and one can charge up to 100% off-peak from grid by default, use during on-peak daily. Would still be horrible for summer/AC required periods, but I wonder if that's actually a better option if you can take the 30% tax credit from purchase. Of course, just getting under NEM2.0 is ideal, but thinking after NEM3.0 is live.

I took a swag at estimating this using the new SDGE EV-TOU-5 rates there were mentioned above as the differential is the largest that I have seen. Taking a best case of discharging 90% of the PW (13.7kWh * 0.90 = 12.15 kWh) during the Peak period and then recharging 13.565 kWh (90% efficiency plus the 0.2kWh daily loss = (12.15/0.9+0.2) ) I get the following:

Season​	TOU​	Rate​	kWh​	Price​
Summer	Peak	$0.8160​	12.15​	$9.9144​
Summer	Off-Peak	$0.4810​	0​	0​
Summer	Super Off-Peak	$0.1540​	13.70​	$2.1098​
Summer	Days	153​		$1,194.10​
Winter	Peak	$0.5110​	12.15​	$6.20865​
Winter	Off-Peak	$0.4480​	0​	0​
Winter	Super Off-Peak	$0.1450​	13.70​	$1.9865​
Winter	Days	212​		$895.10​
			Year	$2,089.20​

So, theoretically you could save $2,089.20/year and with a PW at $13,500 minus the 30% ITC rebate costing $9,450 it would pay for itself in 4.5 years. Adjusting for 70% Peak and 30% Off-Peak the yearly saves drops to $1,507.50 with a payoff in 6.3 years. In these extreme cases it would make sense, but I think it is marginally in the real world.

 

[getakey]

$.816/kWh? Wow

 

[STS-134]

The updated tariffs have been published, generation costs are up, but distribution costs are down and the PCIA cost is way down, so there is a weird mix. The E-TOU-C and EV2 rates are lower, but the E-TOU-D rate is higher and the climate credit is also slightly lower for 2023.

All tariffs - Tariffs

If you look at the spread between the electricity tariffs and the natural gas tariffs, the COP required for my heat pump to beat the gas furnace keeps getting lower and lower. It is now more economical for me to operate the heat pump all the way down to around 20°F outside, which is about the record low ever recorded.

 

[Redhill_qik]

I took a swag at estimating this using the new SDGE EV-TOU-5 rates there were mentioned above as the differential is the largest that I have seen. Taking a best case of discharging 90% of the PW (13.7kWh * 0.90 = 12.15 kWh) during the Peak period and then recharging 13.565 kWh (90% efficiency plus the 0.2kWh daily loss = (12.15/0.9+0.2) ) I get the following:

Season​	TOU​	Rate​	kWh​	Price​
Summer	Peak	$0.8160​	12.15​	$9.9144​
Summer	Off-Peak	$0.4810​	0​	0​
Summer	Super Off-Peak	$0.1540​	13.70​	$2.1098​
Summer	Days	153​		$1,194.10​
Winter	Peak	$0.5110​	12.15​	$6.20865​
Winter	Off-Peak	$0.4480​	0​	0​
Winter	Super Off-Peak	$0.1450​	13.70​	$1.9865​
Winter	Days	212​		$895.10​
			Year​	$2,089.20​

So, theoretically you could save $2,089.20/year and with a PW at $13,500 minus the 30% ITC rebate costing $9,450 it would pay for itself in 4.5 years. Adjusting for 70% Peak and 30% Off-Peak the yearly saves drops to $1,507.50 with a payoff in 6.3 years. In these extreme cases it would make sense, but I think it is marginally in the real world.

Since the SDGE rates spread is so large and the Summer period is longer (6/1 to 10/31) I ran the numbers for PG&E with the current EV2 rates.

Season​	TOU​	Rate​	kWh​	Price​
Summer	Peak	$0.5532​	12.15​	$6.721623​
Summer	Off-Peak	$0.4437​	0​	0​
Summer	Super Off-Peak	$0.2417​	13.70​	$3.311427​
Summer	Days	122​		$416.04​
Winter	Peak	$0.4271​	12.15​	$5.189387​
Winter	Off-Peak	$0.4104​	0​	0​
Winter	Super Off-Peak	$0.2417​	13.70​	$3.311427​
Winter	Days	243​		$456.34​
			Year​	$872.39​

This drops the best case scenario to a payback of 10.8 years and the 70/30 case with a yearly savings of $445.39 and a payback of 21.2 years.

 

[getakey]

Since the SDGE rates spread is so large and the Summer period is longer (6/1 to 10/31) I ran the numbers for PG&E with the current EV2 rates.

Season​	TOU​	Rate​	kWh​	Price​
Summer	Peak	$0.5532​	12.15​	$6.721623​
Summer	Off-Peak	$0.4437​	0​	0​
Summer	Super Off-Peak	$0.2417​	13.70​	$3.311427​
Summer	Days	​ 122​		$416.04​
Winter	Peak	$0.4271​	12.15​	$5.189387​
Winter	Off-Peak	$0.4104​	0​	0​
Winter	Super Off-Peak	$0.2417​	13.70​	$3.311427​
Winter	Days	​ 243​		$456.34​
			Year​	$872.39​

This drops the best case scenario to a payback of 10.8 years and the 70/30 case with a yearly savings of $445.39 and a payback of 21.2 years.

I have not really compared before, but EV1 peak is higher than EV2, but Off Peak is lower

 

[skepticcyclist]

Anyone have updated SCE info?

 

[Redhill_qik]

I have not really compared before, but EV1 peak is higher than EV2, but Off Peak is lower

EV1 is a grand fathered rate plan and not available any longer, so I'm not going to run the numbers for it . The NEM 3.0 E-ELEC rate is published and this is what that looks like and it is even worse.

Season	TOU	Rate​	kWh	Cost
Summer	Peak	$0.5298​	12.15​	$6.4369​
Summer	Off-Peak	$0.3679​	0​	0​
Summer	Super Off-Peak	$0.3112​	13.70​	$4.2639​
Summer	Days	122​		$265.12​
Winter	Peak	$0.2983​	12.15​	$3.6241​
Winter	Off-Peak	$0.2762​	0​	0​
Winter	Super Off-Peak	$0.2623​	13.70​	$3.5939​
Winter	Days	243​		$7.33​
		​	Year​	$272.45​

This reduces the payback period to 34.7 years and with the 70/30 scenario it actually costs an extra $63.73 turning of the arbitrage during the winter does have a benefit of $193.13 in the summer with a payback period of 48.9 years. And that doesn't include the $15/month charge to be on the plan. You need solar in NEM 3.0 or nothing makes sense.

Note: I did not include the $16/month charge in the SDGE calcs.

 

[power.saver]

Anyone have updated SCE info?

You can find them here.

 

[getakey]

EV1 is a grand fathered rate plan and not available any longer, so I'm not going to run the numbers for it . The NEM 3.0 E-ELEC rate is published and this is what that looks like and it is even worse.

Season	TOU	Rate​	kWh	Cost
Summer	Peak	$0.5298​	12.15​	$6.4369​
Summer	Off-Peak	$0.3679​	​ 0​	0​
Summer	Super Off-Peak	$0.3112​	13.70​	$4.2639​
Summer	Days	​ 122​		$265.12​
Winter	Peak	$0.2983​	12.15​	$3.6241​
Winter	Off-Peak	$0.2762​	​ 0​	0​
Winter	Super Off-Peak	$0.2623​	13.70​	$3.5939​
Winter	Days	​ 243​		$7.33​
		​	Year​	$272.45​

This reduces the payback period to 34.7 years and with the 70/30 scenario it actually costs an extra $63.73 turning of the arbitrage during the winter does have a benefit of $193.13 in the summer with a payback period of 48.9 years. And that doesn't include the $15/month charge to be on the plan. You need solar in NEM 3.0 or nothing makes sense.

Note: I did not include the $16/month charge in the SDGE calcs.

right. I'm on the EV1 plan for a while longer. I just did not realize EV1 Peak was higher. The Peak period is longer and provides more time when the Sun is shining. So, Peak being higher is actually better for me