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Which is the best PG&E TOU Rate for New Installs

Merrill

Merrill
Jan 23, 2013
3,858
1,349
Sonoma, California
My main complaint with not being able to charge from the grid is that at night or in rainy or cloudy days you do not get enough solar to charge your Powerwalls. If you are trying to save money you will need to run your house off the Powerwalls during peak times. Getting the ITC does not help you with the above, if you just want to run in back up mode it is not a problem. So again not being able to charge your Powerwalls from the grid is stupid.
 

getakey

Active Member
Jan 28, 2020
1,255
415
95762
My main complaint with not being able to charge from the grid is that at night or in rainy or cloudy days you do not get enough solar to charge your Powerwalls. If you are trying to save money you will need to run your house off the Powerwalls during peak times. Getting the ITC does not help you with the above, if you just want to run in back up mode it is not a problem. So again not being able to charge your Powerwalls from the grid is stupid.

If everyone could charge from the grid at low rates and get credit by sending back to grid at peak rates, PG&E would not be in business. I'm not a fan of PG&E, just stating that it would not work in the long run. I feel we are lucky to get credit at retail rates. We are like a producer to PG&E. There's an argument to be made that we should be paid the same rate that they buy from other producers.
 

holeydonut

Supporting Member
Jun 27, 2020
1,543
903
East Bay NorCal
If everyone could charge from the grid at low rates and get credit by sending back to grid at peak rates, PG&E would not be in business. I'm not a fan of PG&E, just stating that it would not work in the long run. I feel we are lucky to get credit at retail rates. We are like a producer to PG&E. There's an argument to be made that we should be paid the same rate that they buy from other producers.

I had the same sentiment as you until a few days ago... and H2ofun's thread about grid-charging the Powerwalls revealed that PG&E does seem to encourage using batteries to "get the most" out of a system.

Battery storage for your home

I mean, maybe this is being taken out of context, but they say:

Potentially reduce your energy costs: If you are on a PG&E Time-of-Use rate or Home Charging rate, your battery can charge when electricity is cheaper and discharge for use in your home when electricity from the grid is more expensive.

Since most people on TOU rates already have solar or EV's, it seems PG&E actually wants people to add ESS to further take advantage of TOU. They don't seem to be against grid-charging when rates are low in order to then use that energy when rates go up.

So yeah, the only thing stopping a grid-charged-Tesla-Powerwall is their adherence to the federal ITC requirements where batteries only qualify if they're not routinely grid-charged.

I'm very interested to see what H2ofun found in terms of there being a 5 year expiry on this restriction. It seems that eventually (maybe) Tesla will allow a ITC-funded-ESS-with-solar to grid charge at night to allow almost a reverse TOU to bank solar at higher rates than nighttime production.

But with the math I've estimated, a cloudy day is going to cost a boatload... I won't be able to fill the Powerwalls with enough self-generation to cover sunset-to-midnight, so I'll need to take energy from PG&E at the worst possible rate.

If I could grid-charge on command, then I could monitor weather forecasts and max out the Powerwalls overnight to enter a cloudy day with a bank of energy to get to midnight without any behavior modification.
 

MJ_CA_2019

Member
Aug 19, 2020
142
34
Central CA
But with the math I've estimated, a cloudy day is going to cost a boatload... I won't be able to fill the Powerwalls with enough self-generation to cover sunset-to-midnight, so I'll need to take energy from PG&E at the worst possible rate.

If I could grid-charge on command, then I could monitor weather forecasts and max out the Powerwalls overnight to enter a cloudy day with a bank of energy to get to midnight without any behavior modification.

I'm using the time-based control on Balanced mode and for 2020 we took 3.4 kWh from the grid while exporting 175 kWh (i'm on PG&E TOU-C). My PV system produced nearly 4k kWh less than my home consumption for the year. It seems to me that the PW did exactly what it was supposed to do; minimize / eliminate Peak grid usage and maximize savings.
 

holeydonut

Supporting Member
Jun 27, 2020
1,543
903
East Bay NorCal
I'm using the time-based control on Balanced mode and for 2020 we took 3.4 kWh from the grid while exporting 175 kWh (i'm on PG&E TOU-C). My PV system produced nearly 4k kWh less than my home consumption for the year. It seems to me that the PW did exactly what it was supposed to do; minimize / eliminate Peak grid usage and maximize savings.



I don't think I'm going to be in the same boat as you. Sunrun has the absolute worst designers. I think they're career paper pushers and they never approach a project with the idea of maximizing the homeowner's interest. They maximize the installers interest; so they do way stupid things. Originally they had 10 panels facing Northwest; and I had to go through 2 angry phone calls before they finally relented and pointed the panels Southeast again.

Sunrun enforced some weird setback rules that aren't even on the Contra Costa checklist. So I only fit 23 panels even though technically 25 would have fit (and with less shading).

Since I couldn't get Sunrun to skip their stupid setbacks from my skylights, there's just a lot of dead space and my chimney casts shadows on a couple panels. Anyway, I only expect to make 85-90% of my 2021 usage; and it'll only get worse over time as the panels age/get-dirty.

And based on my experience so far, like today with rain in the morning, I ran out of Powerwall energy by 8pm. I think being able to top off with off-peak night time energy would go a long way to making sure I never use peak power. The TOU rates seem to assume homeowners are all able to get 100% offset systems; but that's kind of a pipe dream for some of us.
 

jjrandorin

Moderator, Model 3, Tesla Energy Forums
Nov 28, 2018
8,910
9,931
Riverside Co. CA
I had the same sentiment as you until a few days ago... and H2ofun's thread about grid-charging the Powerwalls revealed that PG&E does seem to encourage using batteries to "get the most" out of a system.

Battery storage for your home

I mean, maybe this is being taken out of context, but they say:

Potentially reduce your energy costs: If you are on a PG&E Time-of-Use rate or Home Charging rate, your battery can charge when electricity is cheaper and discharge for use in your home when electricity from the grid is more expensive.

Since most people on TOU rates already have solar or EV's, it seems PG&E actually wants people to add ESS to further take advantage of TOU. They don't seem to be against grid-charging when rates are low in order to then use that energy when rates go up.

So yeah, the only thing stopping a grid-charged-Tesla-Powerwall is their adherence to the federal ITC requirements where batteries only qualify if they're not routinely grid-charged.

I'm very interested to see what H2ofun found in terms of there being a 5 year expiry on this restriction. It seems that eventually (maybe) Tesla will allow a ITC-funded-ESS-with-solar to grid charge at night to allow almost a reverse TOU to bank solar at higher rates than nighttime production.

But with the math I've estimated, a cloudy day is going to cost a boatload... I won't be able to fill the Powerwalls with enough self-generation to cover sunset-to-midnight, so I'll need to take energy from PG&E at the worst possible rate.

If I could grid-charge on command, then I could monitor weather forecasts and max out the Powerwalls overnight to enter a cloudy day with a bank of energy to get to midnight without any behavior modification.

Thats what you can do if you dont have solar (charge at night and discharge during the day). Since there is no back feeding at all in such a scenario, then there is no worry from the utility in that scenario.

Nothing in anything anyone has posted has said that they (PGE / SCE / SDGE allow that for a customer who has generation equipment also on their property.
 

h2ofun

Active Member
Aug 11, 2020
2,490
426
auburn, ca
I had the same sentiment as you until a few days ago... and H2ofun's thread about grid-charging the Powerwalls revealed that PG&E does seem to encourage using batteries to "get the most" out of a system.

Battery storage for your home

I mean, maybe this is being taken out of context, but they say:

Potentially reduce your energy costs: If you are on a PG&E Time-of-Use rate or Home Charging rate, your battery can charge when electricity is cheaper and discharge for use in your home when electricity from the grid is more expensive.

Since most people on TOU rates already have solar or EV's, it seems PG&E actually wants people to add ESS to further take advantage of TOU. They don't seem to be against grid-charging when rates are low in order to then use that energy when rates go up.

So yeah, the only thing stopping a grid-charged-Tesla-Powerwall is their adherence to the federal ITC requirements where batteries only qualify if they're not routinely grid-charged.

I'm very interested to see what H2ofun found in terms of there being a 5 year expiry on this restriction. It seems that eventually (maybe) Tesla will allow a ITC-funded-ESS-with-solar to grid charge at night to allow almost a reverse TOU to bank solar at higher rates than nighttime production.

But with the math I've estimated, a cloudy day is going to cost a boatload... I won't be able to fill the Powerwalls with enough self-generation to cover sunset-to-midnight, so I'll need to take energy from PG&E at the worst possible rate.

If I could grid-charge on command, then I could monitor weather forecasts and max out the Powerwalls overnight to enter a cloudy day with a bank of energy to get to midnight without any behavior modification.
I am not looking at the ITC stuff.
 

Merrill

Merrill
Jan 23, 2013
3,858
1,349
Sonoma, California
If everyone could charge from the grid at low rates and get credit by sending back to grid at peak rates, PG&E would not be in business. I'm not a fan of PG&E, just stating that it would not work in the long run. I feel we are lucky to get credit at retail rates. We are like a producer to PG&E. There's an argument to be made that we should be paid the same rate that they buy from other producers.
I’m not saying we would always charge the Powerwalls from the grid it would only be those times when you used a lot of power from the batteries and there was no sun.
 

MJ_CA_2019

Member
Aug 19, 2020
142
34
Central CA
Anyway, I only expect to make 85-90% of my 2021 usage; and it'll only get worse over time as the panels age/get-dirty.

And based on my experience so far, like today with rain in the morning, I ran out of Powerwall energy by 8pm. I think being able to top off with off-peak night time energy would go a long way to making sure I never use peak power. The TOU rates seem to assume homeowners are all able to get 100% offset systems; but that's kind of a pipe dream for some of us.

My 2020 totals were:
  • Solar Produced: 14872 kWh
  • Home Usage: 17993 kWh
  • From Powerwall: 5115 kWh
  • From Grid: 6037 kWh
  • To Grid: 2107 kWh

Peak Only:
  • Solar Produced: 182 kWh
  • Home Usage: 682 kWh
  • From Powerwall: 673 kWh
  • From Grid: 3.4 kWh
  • To Grid: 175 kWh

My point is: I think you are underestimating the ability of the software to protect you from consuming from the grid during peak pricing times. There were many times during 2020 that I was scratching my head why my system was pulling from the grid during off-peak times (both solar producing and sun down times). I'm satisfied with the results.
 
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h2ofun

Active Member
Aug 11, 2020
2,490
426
auburn, ca
My 2020 totals were:
  • Solar Produced: 14872 kWh
  • Home Usage: 17993 kWh
  • From Powerwall: 5115 kWh
  • From Grid: 6037 kWh
  • To Grid: 2107 kWh

Peak Only:
  • Solar Produced: 182 kWh
  • Home Usage: 682 kWh
  • From Powerwall: 673 kWh
  • From Grid: 3.4 kWh
  • To Grid: 175 kWh

My point is: I think you are underestimating the ability of the software to protect you from consuming from the grid during peak pricing times. There were many times during 2020 that I was scratching my head why my system was pulling from the grid during off-peak times (both solar producing and sun down times). I'm satisfied with the results.
do you have gas heating
 

h2ofun

Active Member
Aug 11, 2020
2,490
426
auburn, ca
Yes - gas heat, clothes dryer, and range
IMO, for most, when you have gas, one is not comparing apples to apples. I have a 99.9% electric house. 10 heat pump mini split heads. Electric dryer. Only things gas are my hot water, range, and spa.

I also have a large house. So, the amount of electricity I use to heat this home is a lot. And this year has been way down since we so far, as you know, have had a super mild winter. I will need to run my heat pumps 24/7, so the higher ev2-a rates are a BIG deal.

So for me, the inability to recharge batteries in the winter for the amount I use is a big deal.
 

holeydonut

Supporting Member
Jun 27, 2020
1,543
903
East Bay NorCal
Thats what you can do if you dont have solar (charge at night and discharge during the day). Since there is no back feeding at all in such a scenario, then there is no worry from the utility in that scenario.

Nothing in anything anyone has posted has said that they (PGE / SCE / SDGE allow that for a customer who has generation equipment also on their property.


Based on what @wwhitney mentioned in the other thread (Will PGE okay charging batteries from grid with solar?) it appears that PG&E would allow a customer with generation equipment to grid-charge their batteries as a standard measure. This allows the homeowner to take advantage of TOU rates. It's Tesla that won't allow it when the Powerwall is installed alongside solar due to the ITC requirements.

I don't think anyone here wants to charge their batteries overnight then export the stored energy from their batteries back to the grid at peak time. We're just trying to figure out how to get from sunset to midnight without using peak time energy from the grid.
 

holeydonut

Supporting Member
Jun 27, 2020
1,543
903
East Bay NorCal
I read that from someone elses post, I have no idea. My focus is SGIP ER

Oh ok... all this stuff with the ITC, SGIP, PG&E TOU, NEM, and NEC is just so much of a headache.

But I agree with your sentiment that the more gas appliances you have, the harder it is to avoid using peak power. I have gas central heating and water heater. But my MIL is always cooking up a storm around 6pm and that's when we can get to our daily chores. About 1/2 of the household daily electricity use is between 4pm and 11pm. Maybe I just need to convert my cooktop to gas and solve a bunch of problems.
 
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h2ofun

Active Member
Aug 11, 2020
2,490
426
auburn, ca
Based on what @wwhitney mentioned in the other thread (Will PGE okay charging batteries from grid with solar?) it appears that PG&E would allow a customer with generation equipment to grid-charge their batteries as a standard measure. This allows the homeowner to take advantage of TOU rates. It's Tesla that won't allow it when the Powerwall is installed alongside solar due to the ITC requirements.

I don't think anyone here wants to charge their batteries overnight then export the stored energy from their batteries back to the grid at peak time. We're just trying to figure out how to get from sunset to midnight without using peak time energy from the grid.
There would be people who would abuse, just look at all the abuse in the unemployment stuff as an example.

PG&E comments do not talk about ITC. So yep, if you buy batteries, have no solar, cannot take the ITC, tesla will enable grid charging for you, and one can time shift their hearts out.
 

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