SDGE - Time Of Use (TOU) Rates. Good or bad for Net Metering?

[J.P.M.]

I see from the thread that you folks are pretty technical but I have a basic question.

Background: I bought a Fusion Energi plug-in hybrid last week and gave SDG&E a call about what rate plans are best for me. The rep starts by telling me that we just missed out on a 25 day window that we were notified by mail of that would have allowed us to lock in the TOU DR-SES rate for 4 more years. My wife who gets all the bills said we never got any such thing.

Do I understand it correctly that once the PUC approves it that we will only be credited for energy my panels produce from 3-9 pm vs the current 11-6 pm?

Again I'm not too technical; but that sounds like we are getting shafted: SDG&E gets all the power produced by our (expensive) new panels during peak production hours but only gives me credit for offpeak (and zero) production times.

I'm hoping that I am misunderstanding this. Am I?

You have some of it right, but sounds like you're ill/un informed and don't have the whole story.

First off, POCO's (POwer COmpanies), SDG & E among them, are not out to screw, shaft get even with or otherwise make money off PV users. It may seem that way to current and future PV users, but to the POCO's it's simply business, nothing personal. They don't care what PV users think, nor do they give as much as a wet fart about stuff that non PV users are subsidizing mostly affluent PV users. It's all just business, with net metering in its old iteration(s) being no more than an unsustainable business model. A business can't make money paying as much for a product as they sell it for.

The 07/28/17 deadline for 5 yr. grandfathering is a matter of public record, albeit not well disseminated. For current PV users on NEM, the old times for the DR-SES tariff and others such as the EV-TOU rates will be available for a period of 5 years from PTO (Permisssion to Operate) the PV system, PROVIDED THOSE USERS SIGNED UP BY 07/28/2017. After that date, users not making the grandfathering election cut can be under that tariff, but with the new times in force. Note : The 5 yr. period starts from PTO, not from 07/28/2017.

The new times/etc. were going to be voted on by the CPUC on 08/10/2017. That vote got rescheduled and is now to take place on 08/24, unless it's changed again. There may be a few changes yet, but they seem to be pretty well set.

NEM (Net Energy Metering) will still be around, but the new times and the hourly energy rates associated with those times are less favorable to PV users in primarily three ways:
1.) Peak hours, that is, times when electricity is the most expensive, are changing, going from 11 A.M. to 6 P.M weekdays , to 4 P.M. to 9 P.M. 7 days/week.
2.) The summer season, the one with the horrendous (or great if you're a PV user) rates is going from 6 months down to 5 months.
3.) Under NEM 2.0, there will be a charge for every kWh delivered by the utility (not simply the net difference between what's used and what's customer generated per billing period of ~ $0.01745/kWh.

All that will in general make Net Energy Metering "NEM" (which will still be around), and thus residential PV, less cost effective than in the past, probably something like 22 - 25% less cost effective or, to a first approximation, about that much longer in payback time.

PV users will still get to feed all the power they generate via PV to the grid regardless of when it's generated. In that respect, it's just like the old NEM. It just won't be worth as much because the peak summer billing hours will no longer conform as well to peak generating hours.

It may well be you did not receive notification via mail. Others have said much the same. I don't know if written or other notification matters or not.

One advantage for new NEM users, the new DR-SES tariff and some others (BUT NOTE: NOT ALL NEW TARIFFS), is constructed in such a way, that what a user pays per kWh is independent of how much a customer uses. That means, that for modeling and estimating purposes, a system's annual estimated output can be used to estimate annual system revenue to offset a bill.

So, if a user has their green button data, and a DR-SES or other time only rate, they can run PVWatts, get the hourly output option and estimate annual revenue for their proposed system on a per installed STC kW basis and get a better, or at least easier estimate of how much of a system will produce how much revenue to offset a bill. Provided the annual bill offset is <100 %, for a specific system in a fixed orientation, the modeled revenue for that system to offset a bill will be the same, regardless of the annual usage it offsets.

Tariffs that calculate rates independent of usage such as DR-SES also make finding optimum orientation or orientation revenue comparisons a lot easier, again and at least for modeling/estimating purposes. They also make it easier to see the effects on a bill as a result of time shifting of tasks.

The new NEM tariffs and times will make things a lot more difficult for vendors to prosper. They will also have the effect of lowering PV prices some, as vendors will need to sell into a lower market. Contrary to how I suspect the vendors will spin this, bills for non PV users may stay about the same, but with the new rate structures, PV will offset less of the bill.

It'll be interesting to see how the vendors handle the spin.

[sd_tom]

Not to bring this up again, but felt like this is better than making a new thread about it. We are now in the window of current installations being after Dec 1 2017. I'm still trying to grasp the consequences of the NEM-2.0 + TOU 4-9pm change. So, 'net' metering I assumed to be in terms of kwH.. you make a surplus KWH during day, you use at night, you pay the net of all that. Facing a estimate right now that says it might install post Dec 5th and wondering if I should just wait till solar walls are more economical.

Is it safe to summarize these changes as it not being a net of KwH but now a net of $$ .. you generate x KwH converted to $ at the time of use rate. So, it is much harder to break even if daytime surplus hours are discounted (when converted to $) over nighttime drawn hours (more expensive). Is that the easiest way to think about how these changes impact things?

[sensij]

Is it safe to summarize these changes as it not being a net of KwH but now a net of $$ .. you generate x KwH converted to $ at the time of use rate. So, it is much harder to break even if daytime surplus hours are discounted (when converted to $) over nighttime drawn hours (more expensive). Is that the easiest way to think about how these changes impact things?

Sort of. Most daytime hours are worth more than most nighttime hours, so for most consumption patterns, TOU $$$ can still work out to be better than a straight 1:1 kWh, even if it isn't as good as it once was. However, with the new hours, consumption patterns that end up worse off than they would be on tiered plans are more likely / realistic. Even after Dec 1, you still have until 3/30/18 to get onto a tiered plan if it looks like that will be better for you.

[J.P.M.]

Not to bring this up again, but felt like this is better than making a new thread about it. We are now in the window of current installations being after Dec 1 2017. I'm still trying to grasp the consequences of the NEM-2.0 + TOU 4-9pm change. So, 'net' metering I assumed to be in terms of kwH.. you make a surplus KWH during day, you use at night, you pay the net of all that. Facing a estimate right now that says it might install post Dec 5th and wondering if I should just wait till solar walls are more economical.

Is it safe to summarize these changes as it not being a net of KwH but now a net of $$ .. you generate x KwH converted to $ at the time of use rate. So, it is much harder to break even if daytime surplus hours are discounted (when converted to $) over nighttime drawn hours (more expensive). Is that the easiest way to think about how these changes impact things?

Mostly, but not entirely, you will be charged for the net # of kWh the POCO sends you, probably in 15 minute increments at the rate in effect for that 15 minute increment. You will be credited for the net electricity you send back to the grid in the same way you pay for it. Credits will offset charges. (But, not always. Some tariffs keep kWh's in separate buckets, peak offsetting peak kWh for example. Check w/ your tariff and understand how it works.) If you are an SDG & E cust, $ mostly offset $. In addition, you will be billed an additional ~~ $0.017/kWh or so for every kWh the POCO sends you, irrespective of what you generate. That is, for example, if in any 24 hr. period, you send, say, 40 kWh to the grid during the day, and you consume, say, 20 kWh over the 24 hr. period, with 10 of those 20 kWh of consumption happening when it's dark, you will have a net surplus for that day of (40 - 20) kWh, but you will still be billed for the (20-10) = 10 kWh of NBC, at say, = $0.017/kWh * 10 kWh (the 10 kWh you used when it was dark and thus supplied by the POCO, The 20 kWh surplus you generated that day having no bearing on the NBC.

At trueup, 1X/yr., you will either pay the accrued (use - generation) charges + NBC or, if a net generator over the prior 12 months, you will get ~ $0.027/klWr. for the net excess generation over the prior 12 months and you will still pay the NBC rate for all kWh that the POCO sends you (that is net of nothing) regardless of any surplus.

Under the tariff you'll be billed under, without an EV, as a NEM 2.0 cust. (Schedule DR - SES) the average worth of a kWh of electricity under the new times will be ~ $0.235/kWh. Under the old DR - SES times, the average worth of a kWh of electricity was (and is until the new times take effect in Nov./Dec.??) ~ $0.309/kWh., with those rates independent of the quantity of use under that tariff.

As for your breaking even question, the answer is yes, it'll be a longer time to "payback" or a smaller ROI under the new times. I suspect most all vendors will either soft peddle that or spin it to their own ends.But fact is, PV in San Diego is ~ (.309-.235)/(.309) ~ 23% - 24 % less cost effective because of the change in times.

Do as you wish, but I'd not wait around for battery storage for a bunch of reasons that have little or nothing to do with rates or tariffs.

[sd_tom]

Yeah, San Diego (Clairemont). We are already switched to TOU as we have everything geared around night time use. Nobody is home during day, plug in hybrid EV at night. Though, what I didn't realize was the plan I chose allowed for 400% rates for reduce your use days (hot days).. that pretty much negated everything.

Given our usage patterns, the only thing we can move more during the day is the pool pump.

So, yeah.. the dark blue would become the purplish band roughly

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