Hello from Poway CA

[RichardCullip]

Hello all. New member here. I'm here to glean information, especially about the nitty gritty details of SDG&E billing. I got the PTO from SDG&E in April of 2019 and have figured out most of the billing detail including the NBC and Minimum Monthly Adjustment charges. I'm still a bit confused about the Generation Credit that is applied each month. My system is 12 LG335 panels with a SolarEdge inverter. My roof is south orientated with no shading. I am very pleased with the production so far as it is running about 15% above the forecasted performance provided in the bid. San Diego County Solar was fantastic to work with from initial conversations all the way thru getting PTO from SDG&E. No glitches along the way. So far I'm a very happy solar customer.

[SunEagle]

Hello Richard and welcome to Solar Panel Talk

[J.P.M.]

Are you referring to the columns with headings "NEM credits", "Applied Credits" and "remaining credits" ?

[RichardCullip]

Are you referring to the columns with headings "NEM credits", "Applied Credits" and "remaining credits" ?

Applied Credits. Specifically I'm wondering why the Applied Credit is slightly less than the sum of the Electricity Delivery, DWR Bond, Electricity Generation Charges and the Baseline Adjustment Credit. I'm on the TOU-DR schedule under NEM 2.0 since I just got the PTO back in April of this year. As an example my bill in August was for 84 kWh of On-Peak use. The kWh for the Off-Peak and Super Off-Peak periods were negative as I'm currently generating more than I'm using for those TOU periods. For the 84 kWh of On-Peak demand I was charged $19.87 for Delivery, $0.42 for DWR Bond, $18.19 for Generation with a Baseline Adjustment Credit of -8.74. The sum of these is $29.74. However, SDG&E only gave me a Generation Credit of -$27.88. In summary I was charged $0.3540 per kWh for the 84 kWh and SDG&E only applied a generation credit of $0.3319 per kWh. I'm curious why SDG&E did not apply enough generation credit to cover the cost of those 84kWh. I had more than enough generation credits to cover the full amount. There's something I don't quite understand about the pricing that SDG&E uses to come up with that $0.3319 per kWh of Applied Generation Credit. My confusion can also be applied to the NEM credits listed in the table at the bottom of the bill as the NEM credits is exactly the same value as the Applied Credits. August is not unique. Each month since PTO shows the same pattern.

[Ampster]

I am not familiar with the format of a SDG&E bill but the lack of clarity may be similar to what I and others have seen on PG&E bills. That lack of clarity may be a result of Non Bypassable Charges and how they affect cumulative totals. The only insight I can offer is that there are two buckets of accumulated NEM balances that will be taken into account at True Up. They are NBC charges and other NEM charges.

[RichardCullip]

I am not familiar with the format of a SDG&E bill but the lack of clarity may be similar to what I and others have seen on PG&E bills. That lack of clarity may be a result of Non Bypassable Charges and how they affect cumulative totals. The only insight I can offer is that there are two buckets of accumulated NEM balances that will be taken into account at True Up. They are NBC charges and other NEM charges.

Like PG&E the SDG&E bill does makes it difficult to follow the nitty gritty details of their charges. By working with the 15 min interval usage data downloaded from SDG&E website I can duplicate all of the bill components except for the price per kWh used in the NEM Charges and the Applied Credits. For my current situation it's more of an intellectual curiosity since my SDG&E bills total up to the monthly minimum charge and it doesn't really matter how SDG&E breaks that down into individual bill components.. That being said, I'm a detailed spreadsheet guy who has a hard time sleeping when numbers and formulas don't quite add up.

[J.P.M.]

Applied Credits. Specifically I'm wondering why the Applied Credit is slightly less than the sum of the Electricity Delivery, DWR Bond, Electricity Generation Charges and the Baseline Adjustment Credit. I'm on the TOU-DR schedule under NEM 2.0 since I just got the PTO back in April of this year. As an example my bill in August was for 84 kWh of On-Peak use. The kWh for the Off-Peak and Super Off-Peak periods were negative as I'm currently generating more than I'm using for those TOU periods. For the 84 kWh of On-Peak demand I was charged $19.87 for Delivery, $0.42 for DWR Bond, $18.19 for Generation with a Baseline Adjustment Credit of -8.74. The sum of these is $29.74. However, SDG&E only gave me a Generation Credit of -$27.88. In summary I was charged $0.3540 per kWh for the 84 kWh and SDG&E only applied a generation credit of $0.3319 per kWh. I'm curious why SDG&E did not apply enough generation credit to cover the cost of those 84kWh. I had more than enough generation credits to cover the full amount. There's something I don't quite understand about the pricing that SDG&E uses to come up with that $0.3319 per kWh of Applied Generation Credit. My confusion can also be applied to the NEM credits listed in the table at the bottom of the bill as the NEM credits is exactly the same value as the Applied Credits. August is not unique. Each month since PTO shows the same pattern.

Thank you.

FWIW: As for the difference between the applied credit and the sum of other terms, I believe the generation credit/kWh is reduced by the NBC.

$0.3540 - $0.3319 = $0.0221.

The current NBC rate effective 08/01/2019 is $0.02341/kWh, or $1.966 for 84 kWh.

($0.02341- $0.0221) * 84 = $0.11 difference. Depending on where you live in SDG & E's service area, there is often some small tax consideration(s) that may apply (or not, or partially) to the NBC. I suspect that's where the remaining $0.11 might be.

To my experience, there is also often some small rounding by SDG & E that looks to me to come from getting usage and net generation in 15 minute increments and billing in whole kWh, but I don't claim to be knowledgeable about how they do it and so far they haven't graced me withy any I sight in such matters.

[RichardCullip]

Thank you.

FWIW: As for the difference between the applied credit and the sum of other terms, I believe the generation credit/kWh is reduced by the NBC.

$0.3540 - $0.3319 = $0.0221.

The current NBC rate effective 08/01/2019 is $0.02341/kWh, or $1.966 for 84 kWh.

($0.02341- $0.0221) * 84 = $0.11 difference. Depending on where you live in SDG & E's service area, there is often some small tax consideration(s) that may apply (or not, or partially) to the NBC. I suspect that's where the remaining $0.11 might be.

To my experience, there is also often some small rounding by SDG & E that looks to me to come from getting usage and net generation in 15 minute increments and billing in whole kWh, but I don't claim to be knowledgeable about how they do it and so far they haven't graced me withy any I sight in such matters.

Thanks for your insight into the mysteries of SDG&E's NEM 2.0 billing. If I take off the NBC rate and add in the State Surcharge Tax ($.000300 per kWh) and the State Regulatory Fee ($.000580 per kWh) I now can get within a penny, if not exactly on, the amount SDG&E calculates for my NEM charges and Applied Credits. My final results are closest if I add up the 15min interval data and then round the NBC kWh values to the nearest whole number.

I can now quit agonizing over the details of SDG&E's billing details.

[J.P.M.]

Thanks for your insight into the mysteries of SDG&E's NEM 2.0 billing. If I take off the NBC rate and add in the State Surcharge Tax ($.000300 per kWh) and the State Regulatory Fee ($.000580 per kWh) I now can get within a penny, if not exactly on, the amount SDG&E calculates for my NEM charges and Applied Credits. My final results are closest if I add up the 15min interval data and then round the NBC kWh values to the nearest whole number.

I can now quit agonizing over the details of SDG&E's billing details.

You're most welcome.

Welcome to the joys of dealing with POCO (non)cooperation and transparency. You have just scratched the surface.

[RichardCullip]

You're most welcome.

Welcome to the joys of dealing with POCO (non)cooperation and transparency. You have just scratched the surface.

Amen to that. Now I can go on to modeling the effect of adding a plug-in hybrid to my electrical demand early next year and determining the new "best" TOU rate schedule for my situation.

[J.P.M.]

Amen to that. Now I can go on to modeling the effect of adding a plug-in hybrid to my electrical demand early next year and determining the new "best" TOU rate schedule for my situation.

Understood.

FWIW, I started modeling that mod. (adding an EV) by assuming all charging was done at super off peak and added the usage to my non EV usage and then get on a T.O.U. tariff like DR-SES.

If an EV does appear in my future, depending on how much electricity I pump into it, a T.O.U. rate may/may not make sense for me.

Ah, the joys of 8,760+ row spreadsheets.The spreadsheets I have done will take any SDG & E tariff with min. modification, so it's fairly easy to get reasonable #'s for approx. dart throws of consequences of various scenarios.

[Ampster]

Amen to that. Now I can go on to modeling the effect of adding a plug-in hybrid to my electrical demand early next year and determining the new "best" TOU rate schedule for my situation.

Mine is another perspective. I have also done extensive modeling and some time ago came to a different conclusion than your neighbor. I have been driving EVs since 2012 and put over 120k miles on them since then. One cannot measure the ROI on an automobile purchase unless it is used entirely for business. I have come to the conclusion that driving an EV results in a lower cost per mile of transportation for me and my significant other.

In addition to the lower cost of transportation it has allowed me to further leverage my investment in solar. I can go into more detail if you or anyone else is interested.

[J.P.M.]

Mine is another perspective. I have also done extensive modeling and some time ago came to a different conclusion than your neighbor. I have been driving EVs since 2012 and put over 120 I miles on them since then. . One cannot measure the ROI on an automobile purchase unless it is used entirely for business. I have come to the conclusion that driving an EV results in a lower cost per mile of transportation for me and my significant other.

In addition to the lower cost it has allowed me to further leverage my investment in solar. I can go into more detail if you or anyone else is interested.

Who said anything about ROI ? I'm talking (writing) about being heads' up and informed about the best POCO tariff that minimizes the amount of $$ that EV charging adds to my electric bill.

A vehicle is, for non business applications, a mode of point A to point B transportation. it's an expense with no ROI.

Also, if I'm the neighbor your referring to, I don't know where you got the notion but please note that I haven't reached any conclusion(s) yet as to whether or not an EV is in my future. Looks like it'll happen for me, but that's not a slam dunk as to when or in what form it'll take. No conclusions have been reached at this time. As it seems important to you, I'll be sure to let you know when I do reach any conclusions as to what vehicles I drive. I expect the decision will be based partly on economics, partly on reliability, availability, serviceability and the ease of obtaining those things, but mostly on ego. That Porsche Taycan is sure looking good at this time. Maybe in a year or two.

[Ampster]

Who said anything about ROI ?

I mentioned ROI only to frame the discussion in terms of personal use. No need to feel it was a personal insult.

A vehicle is, for non business applications, a mode of point A to point B transportation. it's an expense with no ROI.

No need to restate that since that was my point in the first place and as I mentioned I was just trying to foreclose any irrelevant banter.

Also, if I'm the neighbor your referring to, I don't know where you got the notion but please note that I haven't reached any conclusion(s) yet as to whether or not an EV is in my future....... No conclusions have been reached at this time. ....... That Porsche Taycan is sure looking good at this time. Maybe in a year or two.

Haha, yes you are the neighbor I was referring to. I guess we will have to agree to disagree about whether no decision is a decision or conclusion or not. No worries, it makes an interesting conversation and gives you an opportunity to keep your post count up and add several paragraphs to the server storage.
When I said I have reached a different conclusion 7 years ago I literally made a decision to drive an EV and you have not made a decision yet. I think that was factually correct is it not? Whether you want to call that a non decision or no conclusion is your choice. The Taycan sounds like it is going to be a great EV. What are you waiting for? Or is the Taycan discussion just a red herring?

[Ampster]

Who said anything about ROI ? I'm talking (writing) about being heads' up and informed about the best POCO tariff that minimizes the amount of $$ that EV charging adds to my electric bill.......

Yes that is exactly what I was referring to when I said leverage existing solar. For example several years ago on NEM 1.0 my True up consisted of a 1,000 or so of net kWhrs consumption. My NEM dollar balance was a credit of maybe $100. The True up calculation washed out that credit against my consumption. Much of that consumption was EV charging at off peak and the dollar credit was from generation at Peak and Mid peak. It may sound counterintuitive but I deliberately picked a TOU rate with the greatest differential between Peak and Off Peak which also had the highest Peak rate.
I am in a different situation in a new location with NEM 2.0 and we will see how that works out.