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Choosing PG&E Rate Plan (Solar with Storage)

I have about 15KW of Solar and 3 Power Walls and have been on the old E-6 plan. PG&E is eliminating E-6 and wants me to choose a new plan and says they will select E-TOU-C if I do nothing. When I look at the E-TOU-E versus E-TOU-D, its not obvious with a model which is better.

Summer time and rates for E-TOU-C are 4-9PM peak with below baseline 40 cents per KWHr and above 49 cents with off peak 43 cents and 34 cents respectively.

Summer time and rates for E-TOU-D are 5-8PM peak with no baseline.

It would seem that the amount above baseline I run during summer would be key.

My 3 Power Walls can shift much of my solar power into the 4-9PM or 5-8PM but the TOU-C gain is 6 cents per KWHr and TOU-D is13 cents. At a glance, the 13 cents appears better. But I know PG&E chose these numbers for a reason.

My usage is quite high. Has anyone modeled or done an analysis as to which is better. I don't even know my baseline.

thoughts. Thanks
 

h2ofun

Active Member
Aug 11, 2020
4,154
1,074
auburn, ca
I have about 15KW of Solar and 3 Power Walls and have been on the old E-6 plan. PG&E is eliminating E-6 and wants me to choose a new plan and says they will select E-TOU-C if I do nothing. When I look at the E-TOU-E versus E-TOU-D, its not obvious with a model which is better.

Summer time and rates for E-TOU-C are 4-9PM peak with below baseline 40 cents per KWHr and above 49 cents with off peak 43 cents and 34 cents respectively.

Summer time and rates for E-TOU-D are 5-8PM peak with no baseline.

It would seem that the amount above baseline I run during summer would be key.

My 3 Power Walls can shift much of my solar power into the 4-9PM or 5-8PM but the TOU-C gain is 6 cents per KWHr and TOU-D is13 cents. At a glance, the 13 cents appears better. But I know PG&E chose these numbers for a reason.

My usage is quite high. Has anyone modeled or done an analysis as to which is better. I don't even know my baseline.

thoughts. Thanks
I thought you could not do E-TOU-C with batteries unless you have medical?
 

holeydonut

Active Member
Supporting Member
Jun 27, 2020
3,676
3,192
East Bay NorCal
I thought you could not do E-TOU-C with batteries unless you have medical?


The barring of E-TOU-C with Powerwalls was an SGIP thing. Pretty sure lots of people have Powerwalls with E-TOU-C as long as they didn't touch the SGIP trough.

But for @pgrovetom1 , I think the decision between rate plans boils down to how much coverage his 3x powerwalls provide across a normal daily cycle; and if he's an annual net generator or a net consumer of solar for NEM 2.0 true ups.

I have 3 Powerwalls. They can cover my daily usage from 3PM to Midnight without the need for grid charging. But my solar is piddley (**** YOU PG&E YOU ****ERS ***HOLES PG&E SUCKS SUCKS SUCKS) at only 7kW. This means I am a net consumer on my NEM cycle. The main culprit for my deficit is my EV. So, I benefit by being on EV2A since the batteries make me agnostic to daily NEM peak-time TOU rates. And I can time my EV charging to off-peak times and the NEM deficit only requires grid energy at the lowest possible rate available (without using a legacy rate plan).

If instead my solar were super beefy and I was a net generator, it wouldn't really matter which rate plan I was on.

However, if my home used a lot of electricity and the 3x Powerwalls could not power the home from 3pm to midnight, then E-TOU-C is probably better. My heating is gas, but if I had electric heating, I doubt the 3x Powerwalls could power through the peak time during winter months without grid charging (which requires EV2A and PG&E to lift my NEM2-MT restrictions). The shoulder and peak time rates under EV2A are nasty, and it's best to avoid those if the Powerwalls can't buffer the home from TOU rates.
 
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I have PG&E. No storage, but 7.5Kw system. I found the regular Domestic Tier plan best, since with Solar, I am able to stay in Tier #1 and never go over the Baseline per month. My baseline is 9Kwh per day Winter and 46kWh per day in Summer. I'm paying $0.28 per kWh in Tier #1, and my Solar is costing me $0.20 per kWh. My net metering just about breaks even at the end of the yearly billing cycle. The TOU plans all would cost me a lot more, and usless in my hot Palm Springs Summers, now that they have backed up the Peak hours to 5-9 or 4-9pm when my solar stops and the crazy peak rates are around $0.56 per kWh !!
 

h2ofun

Active Member
Aug 11, 2020
4,154
1,074
auburn, ca
The barring of E-TOU-C with Powerwalls was an SGIP thing. Pretty sure lots of people have Powerwalls with E-TOU-C as long as they didn't touch the SGIP trough.

But for @pgrovetom1 , I think the decision between rate plans boils down to how much coverage his 3x powerwalls provide across a normal daily cycle; and if he's an annual net generator or a net consumer of solar for NEM 2.0 true ups.

I have 3 Powerwalls. They can cover my daily usage from 3PM to Midnight without the need for grid charging. But my solar is piddley (**** YOU PG&E YOU ****ERS ***HOLES PG&E SUCKS SUCKS SUCKS) at only 7kW. This means I am a net consumer on my NEM cycle. The main culprit for my deficit is my EV. So, I benefit by being on EV2A since the batteries make me agnostic to daily NEM peak-time TOU rates. And I can time my EV charging to off-peak times and the NEM deficit only requires grid energy at the lowest possible rate available (without using a legacy rate plan).

If instead my solar were super beefy and I was a net generator, it wouldn't really matter which rate plan I was on.

However, if my home used a lot of electricity and the 3x Powerwalls could not power the home from 3pm to midnight, then E-TOU-C is probably better. My heating is gas, but if I had electric heating, I doubt the 3x Powerwalls could power through the peak time during winter months without grid charging (which requires EV2A and PG&E to lift my NEM2-MT restrictions). The shoulder and peak time rates under EV2A are nasty, and it's best to avoid those if the Powerwalls can't buffer the home from TOU rates.
Yep, I have electric minisplits. Now 4 PW's just for heating. Got them set at 40% reserve. And nope, I cannot make it through a day without pulling from the grid since the solar cannot recharge enough, especially now with the rain and clouds we are getting.
 

cwied

Active Member
Jan 13, 2015
1,127
838
San Mateo, CA
I have about 15KW of Solar and 3 Power Walls and have been on the old E-6 plan. PG&E is eliminating E-6 and wants me to choose a new plan and says they will select E-TOU-C if I do nothing. When I look at the E-TOU-E versus E-TOU-D, its not obvious with a model which is better.


thoughts. Thanks
You might also want to check out EV2A. EV2A is available on a pilot basis to customers with batteries, even if you don't have an EV. The main question is whether you expect to pay money at true-up or not. If you're going to overproduce, the price differential gives you very little real benefit. If you expect to pay at true-up, EV2A can help because it has a much bigger off-peak to peak differential. Can you cover 3pm to midnight on your batteries?
Unfortunately you don't get access to export everything with 3 Powerwalls, so you can't shift solar production into peak, but shifting your load to off-peak can still be a significant gain given the price differential.
 

jjrandorin

Moderator, Model 3, Tesla Energy Forums
Moderator
Nov 28, 2018
17,606
23,687
Riverside Co. CA
I have PG&E. No storage, but 7.5Kw system. I found the regular Domestic Tier plan best, since with Solar, I am able to stay in Tier #1 and never go over the Baseline per month. My baseline is 9Kwh per day Winter and 46kWh per day in Summer. I'm paying $0.28 per kWh in Tier #1, and my Solar is costing me $0.20 per kWh. My net metering just about breaks even at the end of the yearly billing cycle. The TOU plans all would cost me a lot more, and usless in my hot Palm Springs Summers, now that they have backed up the Peak hours to 5-9 or 4-9pm when my solar stops and the crazy peak rates are around $0.56 per kWh !!

The CA utilities all force a time of use rate on solar now connected now. If you have that rate, you likely connected when they didnt force a TOU rate (like I did).

A tiered rate is much better in general for solar, since you can keep in tier 1 if sized correctly and you dont have to worry about "when" you use your power. Since people in CA cant sign up for those rates any longer with solar, our legacy tiered domestic rates are not really relevant to this discussion, although I acknowledge we have them. This OP cant choose it, though, and neither can anyone else getting PV now in CA.
 
The only logical rate plan with powerwalls is EV2-A. There is not enough price differential between peak and off peak on ETOU-B and ETOU-C for the powerwalls to be viable in non-summer rates due to 90% roundtrip efficiency.
I disagree with this, I have Powerwalls and I'm on E-TOU-C it is more cost effective as a net exported/generator/producer as I can reduce the amount of Powerwall usage and the efficiency loss during the recharge phase to get the maximum amount exported.
 
I have about 15KW of Solar and 3 Power Walls and have been on the old E-6 plan. PG&E is eliminating E-6 and wants me to choose a new plan and says they will select E-TOU-C if I do nothing. When I look at the E-TOU-E versus E-TOU-D, its not obvious with a model which is better.

Summer time and rates for E-TOU-C are 4-9PM peak with below baseline 40 cents per KWHr and above 49 cents with off peak 43 cents and 34 cents respectively.

Summer time and rates for E-TOU-D are 5-8PM peak with no baseline.

It would seem that the amount above baseline I run during summer would be key.

My 3 Power Walls can shift much of my solar power into the 4-9PM or 5-8PM but the TOU-C gain is 6 cents per KWHr and TOU-D is13 cents. At a glance, the 13 cents appears better. But I know PG&E chose these numbers for a reason.

My usage is quite high. Has anyone modeled or done an analysis as to which is better. I don't even know my baseline.

thoughts. Thanks
Our internal analysis indicates that E-TOU-C is better for customers without an excess of solar (but demand under or just over the baseline allotment), and EV2A is better as the PV system gets larger and the customer approaches being a net generator.

The delta isn't very significant unless the PV system is pretty small and if the ESS aren't large enough to cover power used on peak.

Also, if the customer usage exceeds the baseline significantly, E-TOU-C starts to get a larger delta compared with EV2A.
 
Last edited:

holeydonut

Active Member
Supporting Member
Jun 27, 2020
3,676
3,192
East Bay NorCal
I disagree with this, I have Powerwalls and I'm on E-TOU-C it is more cost effective as a net exported/generator/producer as I can reduce the amount of Powerwall usage and the efficiency loss during the recharge phase to get the maximum amount exported.


I’ve learned that if wwhitney and redhill_qik disagree with you, then you are wrong.

Source: I’ve disagreed with them before and I was wrong.
 

h2ofun

Active Member
Aug 11, 2020
4,154
1,074
auburn, ca
Our internal analysis indicates that E-TOU-C is better for customers without an excess of solar (but demand under or just over the baseline allotment), and EV2A is better as the PV system gets larger and the customer approaches being a net generator.

The delta isn't very significant unless the PV system is pretty small and if the ESS aren't large enough to cover power used on peak.

Also, if the customer usage exceeds the baseline significantly, E-TOU-C starts to get a larger delta compared with EV2A.
Since I am a large net generator, would I be better off on EV2A? Currently I do not seen anything back from my batteries
 
Since I am a large net generator, would I be better off on EV2A? Currently I do not seen anything back from my batteries
Do you currently have a large credit at your annual true-up? If so, then the rate plan doesn't matter and the main concern should be increasing your net exported kWh while keeping an eye on your cumulative NBCs to avoid going over your annual MDCs. An NBC is currently $0.02666/kWh and a net exported kWh should be a bit above $0.05/kWh, but this isn't an exact offset.
 
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Here is a case
Do you currently have a large credit at your annual true-up? If so, then the rate plan doesn't matter and the main concern should be increasing your net exported kWh while keeping an eye on your cumulative NBCs to avoid going over your annual MDCs. An NBC is currently $0.02666/kWh and a net exported kWh should be a bit above $0.05/kWh, but this isn't an exact offset.
Good point, I had not really considered actually being a net generator, only getting close to it.
 
Our internal analysis indicates that E-TOU-C is better for customers without an excess of solar (but demand under or just over the baseline allotment), and EV2A is better as the PV system gets larger and the customer approaches being a net generator.

The delta isn't very significant unless the PV system is pretty small and if the ESS aren't large enough to cover power used on peak.

Also, if the customer usage exceeds the baseline significantly, E-TOU-C starts to get a larger delta compared with EV2A.
Here is a test case based on the rates in 2020 that I used to decide.
Annual useage 33MWh
18.8 kW PV system - Annual production 28.3 MWh
2 of 4 Powerwalls are used to self-consume power during peak rates.
Average monthly bill on ETOU-C without med baseline $153
Average monthly bill on EV2-A $87.38

EDIT-The rates have changed but the deltas are similar.
 
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Likely yes, especially if you have good afternoon exposure to your PV during the summer peak hours of 4-9 pm.
Why do you think there would be any benefit? If the cumulative charges/credit are negative at the annual true-up then it is reset to zero, so there is no difference between -$10 versus -$1,500.

I think there is a single CCA that is paying retail rates for excess generation, but everyone else I think is using a multiple of the PG&E net surplus compensation rate and the net kWh.
 
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Why do you think there would be any benefit? If the cumulative charges/credit are negative at the annual true-up then it is reset to zero, so there is no difference between -$10 versus -$1,500.

I think there is a single CCA that is paying retail rates for excess generation, but everyone else I think is using a multiple of the PG&E net surplus compensation rate and the net kWh.
I was wrong, and forgot how net generators are treated.
 

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