PG&E Rates - Solar E-6 vs EV-A
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miimura
Well-known member
Based on my updated spreadsheet, I calculated my energy charges for January - July 2013 on PG&E E-1, E-6, E-9A, EV-A.
E-1 : $390.17
E-6 : $229.64
E-9A: $165.13
EV-A: $247.27
These are totals for the first 7 months of this year. I have only had an EV since the end of April and my solar was installed in December 2012. Here's the detail:
E-1 : $390.17
E-6 : $229.64
E-9A: $165.13
EV-A: $247.27
These are totals for the first 7 months of this year. I have only had an EV since the end of April and my solar was installed in December 2012. Here's the detail:
Dsinned
Well-known member
Miimura, thanks for all your contributions to this topic. So, in your particular case, similar to my situation as far as a modest size PV + two EVs, resulting in a nearly "net zero" true up NEMs balance, it looks like staying grandfathered on E-9A rates is clearly the winner. And then after December 31, 2014 switching to E-6 would probably be the next best choice, correct?
Btw, I met the co-founder of Generaytor.com a few weeks ago while he was in Silicon Valley on business. I believe he is originally from Spain. He was very interested in feedback from end users.
Btw, I met the co-founder of Generaytor.com a few weeks ago while he was in Silicon Valley on business. I believe he is originally from Spain. He was very interested in feedback from end users.
miimura
Well-known member
It looks that way so far. However, you can see that all of my winter data does not have EV usage included. I may run it again with 13kWh/day added to the months before I got my RAV to see the results. This may skew it even more toward E-9A, but if it goes into the higher tiers, it may go more toward EV-A due to the non-tiered pricing.Dsinned said:
miimura
Well-known member
So I went ahead and added an equivalent Off-Peak charging amount of 13kWh/day to Jan-Apr to more accurately model the period before I got the RAV. It drastically changes the picture in the winter. Adding that usage when the solar is generating so little pushes the usage way into the upper tiers. The Tier-Less EV rate schedule then comes very close to E-9A. Adding in November and December will probably make EV-A clearly less than E-9A.
In summary:
E-1: $781.35
E-6: $578.34
E-9A: $390.02
EV-A: $399.96
These are the total amounts that would appear on my solar billing annual True-Up statement for January to July.
Edit: I forgot to change the baseline amount back to winter, so if you saw the short table without the kWh figures, the E-1, E-6, E-9A numbers are slightly lower now. Going from 11.0 to 11.7kWh/day baseline actually changed the outcome so E-9A is still less than EV-A, it was about $5 more.
In summary:
E-1: $781.35
E-6: $578.34
E-9A: $390.02
EV-A: $399.96
These are the total amounts that would appear on my solar billing annual True-Up statement for January to July.
Edit: I forgot to change the baseline amount back to winter, so if you saw the short table without the kWh figures, the E-1, E-6, E-9A numbers are slightly lower now. Going from 11.0 to 11.7kWh/day baseline actually changed the outcome so E-9A is still less than EV-A, it was about $5 more.
Braxus
Active member
I didn't expect this detailed of a discussion when I made the post. Glad to see we're getting some good information here! 
dr_gibberish
Member
DELETED POST
miimura
Well-known member
New totals including August:miimura said:
E-1: $834.45
E-6: $595.15
E-9A: $405.22
EV-A: $436.52
SeaMonster
Well-known member
I have a bigger solar system. 6.3KW produces 44kWh/day in summer. I generate 1.2MWh / month in summer. For me the EV-A rate is a clear winner. I also live in Marin where we created a CCA to take over power purchasing from PG&E. What that means is that I am paid a rather handsome (compared to PG&E) rate for my excess solar. Having higher peak rates and having peak on weekends and winter means my solar makes me more money. I just switched to EV-A. In the dead of winter, my bills will go up from about $13/mo to about $22/mo. But in summer I will go from making about $100/mo to making $130/mo and in April I go from making $20 to making $78.
miimura
Well-known member
If you download your SmartMeter historical data you can use my spreadsheet to add in Off-Peak charging load and recalculate your energy charges on all the relevant rate plans. If you want help with it, PM me and I'll have you send me some SmartMeter CSV data and I'll plug it in for you and send it back with whatever comparison parameters you like.dr_gibberish said:
miimura
Well-known member
Yeah, my solar is really too small for our current situation. I built the house with EV charging in mind (two NEMA 14-50's in the garage), but the solar was not sized for it and would probably not even zero out the annual bill without the EV charging. That's the problem with putting solar on a new house, you don't know what you usage will actually be. Also, the orientation and shading situation is not ideal.SeaMonster said:
waidy
Well-known member
Too bad we don't have CCA in my area. I made way too much power (even with 3 EVs) but am only getting 3+ cents per kWh back.SeaMonster said:
Dsinned
Well-known member
Waidy, same here, but I am closer to net zero. Since my PTO last March, my PG&E smartmeter has decremented from a reading of "99999" to about 99500kWh. This means I sized my solar system so it over generates on average, which should result in "selling back" ~1MWh per year. At <4 cents per kWh, that's not even $40/year at true-up. However, I never will have an electric bill more than $5/mo., which is only that much because of the service charges, utility taxes and whatever other fees are generally tacked on to the bill.
It's really nice to be green! :mrgreen:
It's really nice to be green! :mrgreen:
miimura
Well-known member
Dsinned, you have not yet experienced November, December, January and February on solar. Look at the Jan & Feb in my spreadsheet earlier in this thread. My system generates about 1/4 as much energy per day in the dead of winter. 76% of my calculated YTD energy charges on E-9A with an EV are from January and February. Did your installer give you a month-by-month forecast?
Dsinned
Well-known member
miimura, no, my installer did not give me that info, so I used several online solar calculators to attempt to gain that knowledge.
I could be waaay over estimating the likelihood of over generating after a full year of net metering. -1MWh is probably not even close to what I will be able to "net" in energy credits. And if all that results is a miniscule $40 total reimbursement from PG&E, there is really no incentive to intentionally over generate in the first place; at least not in Northern CA. But, I sure don't want to revert to paying for electricity, so I hope my 4.25kW system will be more than adequate.
I've only had my solar system in operation for half a year so far (since March 2013). My electric power consumption during Summer obviously will be a lot more because of my A/C in frequent use during the day time. It sucks up a whooping 4kW while running. My RAV4 EV uses 7.7kW for about 3 to 4 hours continuously while charging; my Chevy Volt only uses 3.3kW for about the same amount of time per charge. With the exception of the A/C, charging my EVs is only exclusively during off-peak hours (midnight to 7am) and/or on weekends. From October thru May, the A/C will probably hardly ever be used, but my EV charging will be year round at least a couple times per week.
You're quite right in pointing out that during the late Fall thru early Spring - about 6 months total - solar production will be significantly less. I will probably have only 25% to 50% as much production compared to the other 6 months of the year. But, because A/C will not be used nearly as much, consumption will drop substantially as well; though not nearly as much as 50%.
Not until a full 12 months of monthly bills covering normal consumption and solar power generation, will it be possible to verify to determine precisely if how much I sized my systems will turn out to be reasonably close to "net zero". Right now, I am projecting +/- 20%, but of course, to be at ideally at net zero, is the goal as far as maximizing ROI.
I could be waaay over estimating the likelihood of over generating after a full year of net metering. -1MWh is probably not even close to what I will be able to "net" in energy credits. And if all that results is a miniscule $40 total reimbursement from PG&E, there is really no incentive to intentionally over generate in the first place; at least not in Northern CA. But, I sure don't want to revert to paying for electricity, so I hope my 4.25kW system will be more than adequate.
I've only had my solar system in operation for half a year so far (since March 2013). My electric power consumption during Summer obviously will be a lot more because of my A/C in frequent use during the day time. It sucks up a whooping 4kW while running. My RAV4 EV uses 7.7kW for about 3 to 4 hours continuously while charging; my Chevy Volt only uses 3.3kW for about the same amount of time per charge. With the exception of the A/C, charging my EVs is only exclusively during off-peak hours (midnight to 7am) and/or on weekends. From October thru May, the A/C will probably hardly ever be used, but my EV charging will be year round at least a couple times per week.
You're quite right in pointing out that during the late Fall thru early Spring - about 6 months total - solar production will be significantly less. I will probably have only 25% to 50% as much production compared to the other 6 months of the year. But, because A/C will not be used nearly as much, consumption will drop substantially as well; though not nearly as much as 50%.
Not until a full 12 months of monthly bills covering normal consumption and solar power generation, will it be possible to verify to determine precisely if how much I sized my systems will turn out to be reasonably close to "net zero". Right now, I am projecting +/- 20%, but of course, to be at ideally at net zero, is the goal as far as maximizing ROI.
SeaMonster
Well-known member
waidy said:
I an getting 19c/kWh. That's pretty reasonable.
These adjacent/surrounded utility residential rates: Silicon Valley Power 10c/kWH residential no tiers or times. Alameda Power 12c. SMUD 11c up to 700kWH. Avg E-1 rate is 18c/kWH per PG&E (in the E-1 tarrif).
[This is what you pay these neighboring utilities. You decide if PG&E overcharges residences for electricity.]
PG&E will pay about 3c/kWH for excess kWH at your true-up. I would expect them to find a way to NOT credit you their peak kWH rates for your daytime excess production, for you to use to buy off-peak electricity - during their General Rate Case in (GRC) 2014.
[This is what you pay these neighboring utilities. You decide if PG&E overcharges residences for electricity.]
PG&E will pay about 3c/kWH for excess kWH at your true-up. I would expect them to find a way to NOT credit you their peak kWH rates for your daytime excess production, for you to use to buy off-peak electricity - during their General Rate Case in (GRC) 2014.
SeaMonster
Well-known member
srl99 said:
Uh, what are those rates? PG&E does not PAY 18c/kWh. They may charge that for generation, and they may show that amount on a monthly NEM statement. But they don't pay that out for end of the year, true-up payouts.
miimura
Well-known member
It turned out that for the full year E-9A was still cheaper than EV-A in my situation. At one point, early in my analysis, I thought I might go back to E-6 when I'm kicked off E-9. According to these numbers, EV-A will be much better for my situation.miimura said:
Summary of Calculated Annual Energy Charges:
E-1: $1,468.85
E-6: $1,129.21
E-9A: $817.32
EV-A: $837.35
The Excel spreadsheet to generate this from your own SmartMeter data is on Google Drive here: PGE Electric Rate Calculator_V1.6.xlsx.
I also did one more calculation to back out my solar generation to see how much my bill would be without solar. Now, I know this is not a very good or particularly valid comparison because no sane person would stay on E-1 with an EV, but here it is.
The main reason I did it this way is that I currently have no way to extract the data for my solar generation by TOU period. If I spent a bunch of time on it, I could probably extract the data from Enphase Enlighten. Anyway, according to this, my annual energy cost would be $2,342 higher on E-1 without solar. Even for the Jan-Apr period when I didn't have an EV, my bill would have been $462 more. For the first 4 months, my interest payments on my HELOC for the amount of my solar system were only $254, so I saved $52 per month more on my energy bill than the interest on the solar system. Actually, now that I think about it, my ACTUAL savings is E-6 with solar vs. E-1 without solar. That comes to almost exactly $60/mo savings after interest expense because the E-6 bill is lower than E-1 with solar.
One more note about solar true-up. When PG&E installed my NEM SmartMeter after my solar install in December 2012, the usage continued to go to the conventional billing system, not the Solar NEM billing system. When they finally got my account set up in the NEM billing system and backed the charges out of my regular bill, the TOU usage amounts were obviously wrong. I complained to Solar Customer Service and had to talk to 3 people before I convinced them to go back to the original SmartMeter data and recalculate it. They finally did and I got a revised true-up statement. Several months later I noticed that there was no dollar amount accumulated for that first month in my true-up. I got the automatically generated full year true-up bill and paid the balance after it was transferred to my regular bill. Then I received another "corrected" true-up statement, actually 12 envelopes in the mail with each of the 12 monthly true-up statements. Since I have been doing all these crazy calcs based on my SmartMeter data, I also replicated the calculations for my actual billing cycles and found a significant discrepancy, 30kWh, between what I was billed and what was in the SmartMeter data. It turns out that PG&E is missing the SmartMeter data for one 24 hr period in March. It seems like they estimated the missing data by repeating the usage for the prior 24 hours. The problem is that the prior day was a particularly low generation day and was the highest net usage of the whole month. The average of the 6 days surrounding the missing day was only 22kWh. I called the PG&E Solar Customer Service Center and they said they will get back to me regarding how they "interpolated" my usage for billing purposes.
