TOU for SCE in Southern California analysis

[lkruper]

If all your baseline usage (monthly export minus consumption) is during super-off-peak then yes, up to your baseline. But then you might be better off on TOU-A which has no monthly fee (correction: $0.93 fee), especially if you can limit usage during the day and "sell" back to SCE at a higher rate.

The map lists regions (eg 10,12,16). Do these numbers directly correspond to the baseline in kWH?

[gvl]

If you follow the CPUC proceedings, you will see that including a baseline credit or allocation will become a standard feature of TOU plans for all of the IOU's going forward. SCE is actually ahead of the curve on this one.

I was implying that we don't know the future TOU rates. As one extreme example if everyone installs solar the super-off peak may actually shift to daytime

[sensij]

At this time at least...

If you follow the CPUC proceedings, you will see that including a baseline credit or allocation will become a standard feature of TOU plans for all of the IOU's going forward. SCE is actually ahead of the curve on this one.

[gvl]

Just another reason why sizing to produce 100% of consumption is not optimal.

At this time at least...

[gvl]

I was looking at the CA TOU B. Am I interpreting this correctly? The nighttime rate is 11 cents and the baseline is 10 cents, so power used in that tier is actually only 1 cent?

If all your baseline usage (monthly export minus consumption) is during super-off-peak then yes, up to your baseline. But then you might be better off on TOU-A which has no monthly fee (correction: $0.93 fee), especially if you can limit usage during the day and "sell" back to SCE at a higher rate.

[sensij]

I was looking at the CA TOU B. Am I interpreting this correctly? The nighttime rate is 11 cents and the baseline is 10 cents, so power used in that tier is actually only 1 cent?

Correct... if all your power consumed was in the super-off peak, and the amount you consumed is less than your baseline allocation (but greater than zero), you would be paying $0.01 / kWh for that power. Same for TOU-D-A. Note the large monthly fee for B ($16/mo), vs A ($0.93 / mo).

Just another reason why sizing to produce 100% of consumption is not optimal.

[lkruper]

So, I am on a journey for anyone interested in joining me...
I am an engineer (aerospace) who is sometimes too analytical for my own good.
I have a fairly new 6kw system that has been operating since Nov 2014 and am already wondering if I should be on TOU.
I have been trying to comprehend SCEs various rate structures and I am convinced that they must be purposely complex to keep people from understanding how they work. Much like the tax codes or legal-speak.
Here is the link to sce rate schedules:

https://www.sce.com/residential/rates/special-time-of-use.htm

To view the TOU rates, scroll down and expand the "+View pricing for these TOU rates" section...
I have several questions, but I will start with the basics

1. I am finding (so far) that the TOU-D-A plan is best for me. This plan shows 1 "on-peak" rate and 2 "off peak" rates (super, regular) . The on peak claims it is "On-Peak: 2 p.m – 8 p.m. (non-holiday weekdays only)" . So, my question is during weekends what is the rate? There are 2 off peak rates. I obviously could assume the super off peak rate, but my experience tells me assuming might cost me money!

2. For the TOU-D-T plan, I would assume that if I find myself in tier 2 (past 130% baseline) that the higher price of electricity is only for consumption not for generation? Or, said another way, they never pay me at anything but tier 1 rates, but can charge me for tier 2 if applicable?

I have tried to model all 3 plans in Excel and have a pretty cool spreadsheet going (it's a little complicated too) and would like to invite anyone interested in checking it in some way as a second set of eyes (more validation of answers seem right, less checking formulas) . I have used my actual hourly gen/consumption data for the last 3 months. I don't think the spreadsheet is perfect yet, I am still making tweaks...but it's getting there.

I was looking at the CA TOU B. Am I interpreting this correctly? The nighttime rate is 11 cents and the baseline is 10 cents, so power used in that tier is actually only 1 cent?

[gvl]

This is what I thought would be the worst month, last year bill for the same period was close to $500 on Schedule D. Sounds almost too good to be true, and may be it is given SCE is having system issues, but maybe not considering the 10c/kWh baseline allocation credit on TOU-A. There is an EV that is charged at super-off-peak, and a hungry pool pump that partially runs during super-off-peak.

[OftheSeven]

TOU-A vs. Domestic rate comparison:

SCE took forever to switch me over from Domestic to TOU-A, so for August, I received two bills. Even though I had to run the A/C during 'peak hours' it was still the better plan:

8_15 Domestic.jpg

8_15 TOU_A.jpg

[propman07]

Latest update is here:
https://www.dropbox.com/s/9v7bogsz5r...ated.xlsm?dl=0

Just got it. Thanks.

[sensij]

Hi-

New to the forum and interested in taking a peek at the spreadsheet that you developed for TOU calculations. Thanks.

David

Latest update is here:

https://www.dropbox.com/s/9v7bogsz5rzdr11/SCE_TOU_JES_updated.xlsm?dl=0

[propman07]

If it helps to have a non-google drive option, I moved it into my dropbox, and it can be accessed by request.

Hi-

New to the forum and interested in taking a peek at the spreadsheet that you developed for TOU calculations. Thanks.

David

[silversaver]

I have tried hard, but I guess I'm still getting credit after all..... ($30 = gain through $0.1 X baseline)

From Aug 12th to Sep 10th, my solar produced 1122kWh and I used 763kWh from SCE. That is total of 1885kWh consumed for the billing period, but guess what, I'm still getting credit from SCE.


Aug 15 $$$.jpg

Aug 15 kWh.jpg

[silversaver]

TOU-D-A is tough to beat. From Aug 12th to 25th, my solar produced 546kWh and I still consumed 284kWh from SCE. Guess what happen to my bill??

[bcroe]

From now on, I'm just like Bob set my ACs in comfort zone and let them run!!!

BTW, from July 14 to Aug 12th, my solar generated 1202kWh

Its certainly nice to just do that, knowing you aren't consuming any fuel, and the electric bill
will still be zero KWH. The primary thing here is to generate the equivalent of about 1000
gallons of propane in a year. The actual need come winter will vary hugely, and not very
predictably. But oversized about 500% (electrical), I managed to buy no propane and get
to the annual true up date and donate 700 KWH to the power company (despite the clouds).
Which is way better than me buying 700 KWH from them.

Last year was cloudy; this year is worse. Summer production is down about 200 KWH a
month, but with the new heat pump reserves are actually higher than last year.

We just had the IREA local energy fair, and I hear talk about building systems here for
around $3 a watt. Nobody talks about clouds & snow. But it sounded like selling SRECs
even at rock bottom market prices, would by itself be enough to pay for the system over
its lifetime. If true, this could be an overriding consideration on array size. May try to
get into this. Bruce Roe