SDG&E's NBC Calculation for NEM-ST

[CharlieEscCA]

I'm sure it's a PITA to post, but if you wouldn't mind sharing, what does the bill look like ?

Thanx,

J.P.M.

Here you go:

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The 05/09/2017 was partial no solar, partial solar. PTO part way into the month. May bill was not TOU. Called to switch to TOU end of April, but had to wait until start of next billing period to take effect.

I'm told if I have a credit at the end, the May $40.04 will come off.

The May bill got auto paid because I thought auto pay would automatically stop because "no payment was required". Wrong. Separate system. No payment was required, but auto pay happens unless you turn it off. I supposedly get my payment credit at true-up. I'll make sure I do.

[CharlieEscCA]

And my spreadsheet, which I need to cross check with bill, calculated an approximate $710 bill if on the tier use with no solar (my spreadsheet thought I had one more day in the month, have to go adjust).

[sensij]

Here you go:

Thank you, this bill really helps.

The "minimum bill" for a 29 day period would be 9.54. Your "total electric charges" and "total service charges" exceed that, so there is no minimum bill adjustment. It does confirm, however, that the non-bypassable charge adjustment (based on the 44 kWh they identify) is chipping in towards the minimum bill, because without that 0.76, even the NEM 1.0 calculation applying the minimum bill to the total electric service would have given $10.15 - $.76 = $9.39, incurring a small minimum bill adjustment.

All of the calculations I've posted before are intact (I think), but I'll double check. The idea that 44 kWh could be coming from the difference in measuring time intervals is actually intact too, because for you to get positive consumption in all three time periods suggests there may be many intervals swinging back and forth between generation and consumption.

[J.P.M.]

Here you go:

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The 05/09/2017 was partial no solar, partial solar. PTO part way into the month. May bill was not TOU. Called to switch to TOU end of April, but had to wait until start of next billing period to take effect.

I'm told if I have a credit at the end, the May $40.04 will come off.

The May bill got auto paid because I thought auto pay would automatically stop because "no payment was required". Wrong. Separate system. No payment was required, but auto pay happens unless you turn it off. I supposedly get my payment credit at true-up. I'll make sure I do.

Thank you. I'll be rooting around in there w/Sensij. Maybe we'll meet.

FWIW, I was cautioned to actively discontinue auto pay before PTO.

[J.P.M.]

Charlie: Did you download your green button data for the 07/09 - 08/07 period ?

Thanx.

[CharlieEscCA]

Charlie: Did you download your green button data for the 07/09 - 08/07 period ?

Thanx.

No. I have no green button data since my meter swap that was needed to get PTO. Prior meter failed to take / accept the NET metering reprogramming. This held up my PTO which should have been 24 hours after county inspection posted to SDGE. And it likely would have dragged on but I started raising a ruckus -- didn't know they had tried over the air programming multiple times but they didn't schedule a roll until I lost my patience getting no real answer when I would call.

The green data shows my new meter, but only offers data before and up to the swap, i.e. the old data.

I guess I need to call into SDGE and have them fix it. But, until senji reported similar NBC low values, I thought I would lie low because I didn't want to affect the situation

[CharlieEscCA]

And the other weird thing is the generation (peak X tariff, semi-peak X tariff, off peak X tariff doesn't match the $ it should be -- it's less than the tariff says.

Like I said in another post, I've truly given up trying to match what I calculate the bill should be vs what they send out.

[sensij]

And the other weird thing is the generation (peak X tariff, semi-peak X tariff, off peak X tariff doesn't match the $ it should be -- it's less than the tariff says.

Like I said in another post, I've truly given up trying to match what I calculate the bill should be vs what they send out.

I think the reason it is less than the tariff is because the NBC's are excluded from that portion of the calculation, but added in later (as I've been saying). I'll be able to take a more detailed look later.

[J.P.M.]

And the other weird thing is the generation (peak X tariff, semi-peak X tariff, off peak X tariff doesn't match the $ it should be -- it's less than the tariff says.

Like I said in another post, I've truly given up trying to match what I calculate the bill should be vs what they send out.

Charlie: I think Sensij has fingered where the NBC's show up. As for that small amount of NBC that is much less than calculated in both your and Sensij's case, I think that might be the difference between 15 minute integrated totals and one hour integrated totals in some SDG & E internal method. That was why I was asking about the green button data.

The mystery continues.

[sensij]

Since all three TOU periods were net consumption, the first set of calculations I've been showing aren't necessary, since there was no NEM credit earned. (Previous remaining NEM credit had been 372.70, new remaining balance = 236.50, with the difference equaling the applied NEM credit of 136.20)

The NEM charges are calculated next, accounting for NBC's.

UDC contribution (subtracting NBC's) = 540 kWh * (0.14184 - 0.01191) = 70.16
EEEC contribution = (61 kWh * 0.35896) + (228 kWh * 0.10375) + (251 * 0.07988) = 21.90 + 23.65 + 20.05 = 65.60
State surcharge tax contribution = 540 kWh * 0.00029 = 0.16
State regulatory fee contribution = 540 kWh * 0.00043 = 0.23
San Diego Franchise fee contribution = nothing, not applicable outside the city of San Diego. lucky you.
Others Franchise fee contribution = calculation for escondido different than san diego, not chasing it down now = 0.04

(70.16 + 65.60 + 0.16 + 0.23 + 0.04) = 136.19, within rounding error of the 136.20 shown under NEM charges on page 4.

That leaves the non-bypassable charges.
DWR-BC contribution = 540 kWh * .00549 = 2.96
Other NBC contribution = 540 kWh * 0.01191 = 6.43

Total implicit NBC's = 9.39

This number is not shown directly, but you can probably verify it with the additional charges and payments

Additional charges and payments this month = (26.40)
Adding 9.39 to that...
My guess is that additional charges and payments shown on last month's bill = (35.79)

Am I right?

Rolling it all up
NEM charges are offset by NEM credits.
That leaves
Implicit NBC's = 9.39
Explicit NBC's = 0.76
Total bill for the month = 9.39 + 0.76 = 10.15

Really, this bill makes sense to me, and i think there is something in how the minimum bill adjustment is calculated that changed between NEM 1.0 and NEM-ST relating to taxes that I need to dig into further (on my bill). My best attempt right now to chase down the 44 kWh responsible for the 0.76 NBC charge would require the 15 min interval data.

[CharlieEscCA]

Since all three TOU periods were net consumption, the first set of calculations I've been showing aren't necessary, since there was no NEM credit earned. (Previous remaining NEM credit had been 372.70, new remaining balance = 236.50, with the difference equaling the applied NEM credit of 136.20)

The NEM charges are calculated next, accounting for NBC's.

UDC contribution (subtracting NBC's) = 540 kWh * (0.14184 - 0.01191) = 70.16
EEEC contribution = (61 kWh * 0.35896) + (228 kWh * 0.10375) + (251 * 0.07988) = 21.90 + 23.65 + 20.05 = 65.60
State surcharge tax contribution = 540 kWh * 0.00029 = 0.16
State regulatory fee contribution = 540 kWh * 0.00043 = 0.23
San Diego Franchise fee contribution = nothing, not applicable outside the city of San Diego. lucky you.
Others Franchise fee contribution = calculation for escondido different than san diego, not chasing it down now = 0.04

(70.16 + 65.60 + 0.16 + 0.23 + 0.04) = 136.19, within rounding error of the 136.20 shown under NEM charges on page 4.

That leaves the non-bypassable charges.
DWR-BC contribution = 540 kWh * .00549 = 2.96
Other NBC contribution = 540 kWh * 0.01191 = 6.43

Total implicit NBC's = 9.39

This number is not shown directly, but you can probably verify it with the additional charges and payments

Additional charges and payments this month = (26.40)
Adding 9.39 to that...
My guess is that additional charges and payments shown on last month's bill = (35.79)

Am I right?

Rolling it all up
NEM charges are offset by NEM credits.
That leaves
Implicit NBC's = 9.39
Explicit NBC's = 0.76
Total bill for the month = 9.39 + 0.76 = 10.15

Really, this bill makes sense to me, and i think there is something in how the minimum bill adjustment is calculated that changed between NEM 1.0 and NEM-ST relating to taxes that I need to dig into further (on my bill). My best attempt right now to chase down the 44 kWh responsible for the 0.76 NBC charge would require the 15 min interval data.

Wow, wow, wow.

I believe you have found it!

NBC may be being charged, but they are hidden from easily viewing them.

As you predicted, The additional charges the month before indeed was (35.79).

This all goes back to my first bill on 5/9 which was for $43.90 total. On the Net Metering Summary page, this was shown as NEM charges of $40.04 and additional charges of 3.86 for a total of 43.90. I could never understand where that split came from, but the 3.86 must have been the implicit NBC on the 222 kWh for the partial solar month.

When my auto pay posted in the June 9 bill, because June was entirely negative, there were no implicit NBC charges. Thus the June net metering summary was:

YTD Net Metering Charges / Credits: 40.04 (carried over from before, and at true up this can go away if I still have a credit)
Non Bypassable charges: 0.10 (the explicit NBC for this month)
Minimum charge adjustment: 9.44
Subtotal: 49.58
Additional charges / payments: (40.04) [which was my 43.90 auto pay which 3.86 went to May implicit NBC and the 40.04 balance now becomes a credit]

Each subsequent bill has seen the additional charges / payments "credit balance" decrease by the implicit NBC charges.

So, we (I) am not escaping NBC, but rather they are coming as you so brilliantly point out as implicit and explicit NBC.

We are, for now, catching a break, because for the most part we are not getting hit for NBC on an hour by hour or a 15 by 15 minute period, but rather by net on the entire billing period plus some small correction factor, i.e. the so stated "Your non-bypassable charges for the month were based on usage of xx kWh".

Congratulations to SDGE for obfuscating the bill. And bigger congratulations to senji who has cracked the code!

P.S. As posted earlier, I have no 15 minute data since the meter swap that finally got me my delayed PTO. But I'm contacting SDGE now that I know that I haven't been getting away with anything that I don't want to bring to their attention

[inspron]

We are, for now, catching a break, because for the most part we are not getting hit for NBC on an hour by hour or a 15 by 15 minute period, but rather by net on the entire billing period plus some small correction factor, i.e. the so stated "Your non-bypassable charges for the month were based on usage of xx kWh".

P.S. As posted earlier, I have no 15 minute data since the meter swap that finally got me my delayed PTO. But I'm contacting SDGE now that I know that I haven't been getting away with anything that I don't want to bring to their attention

Maybe you should delete this post and not contact SDGE since what you stated is very favorable. Best stay quiet with SDGE too

[J.P.M.]

Maybe you should delete this post and not contact SDGE since what you stated is very favorable. Best stay quiet with SDGE too

Don't worry. If they don't know (which I seriously doubt), they soon will. System wide billing errors, even if small are soon discovered. and corrected. If nothing else, I know someone who works for SDG & E in cust. serv. and they're occasional lurkers here.

[CharlieEscCA]

I don't even know if it's really an error anymore. The PUC is going to hold a review of the proper time period to be used for NBC (senji linked this earlier). I'm sure the bil is calculating the way they believe it should be right now.

It's just terribly not obvious that the additional charges line is the NBC of electricity from the grid.

Beyond this, you get full retail applied to your running credit, and then when you pull from that credit, it takes full retail less NBC from your credit (and that's why I didn't understand the electric charges and thought they were less than tariff), and then the NBC shows up in additional charges. Maybe if I didn't have a credit I would have figured it out.

[J.P.M.]

I don't even know if it's really an error anymore. The PUC is going to hold a review of the proper time period to be used for NBC (senji linked this earlier). I'm sure the bil is calculating the way they believe it should be right now.

It's just terribly not obvious that the additional charges line is the NBC of electricity from the grid.

Beyond this, you get full retail applied to your running credit, and then when you pull from that credit, it takes full retail less NBC from your credit (and that's why I didn't understand the electric charges and thought they were less than tariff), and then the NBC shows up in additional charges. Maybe if I didn't have a credit I would have figured it out.

I'm not sure there is one either, but It may be possible a vey small one crept in from integrating/summing different time period lengths, 15 minute vs. one hour, but I'm willing to let SDG & E and others figure it out. I read delivered and received off my meter every A.M. off my meter and those figures agree w/ the 15 minute data. to the kWh.

Question answered in my book.

Sensij gets another attoboy (==10 EE -18 boys).