Thoughts on Solar

While you weren’t watching, SCE - the same SCE that is trying to kill off rooftop solar - just raised their Time-of-Use rates for residential customers. We will break down the increase and show you what it might mean for a couple of potential solar clients.

What are Time-of-Use Rates?

Time-of-Use (or TOU) rates are exactly what they sound like: a rate structure where how much you pay for energy is tied to when you use that energy.  (We wrote a lengthy blog post explaining the differences between TOU rates and Tiered rates, in gory detail!) 

The most common TOU rate for SCE’s residential customers is titled TOU-D, with the 4-9 p.m. window having the highest rates overall.  Compared to a tiered rate -  where your monthly bill is divided into steps based on the volume of energy that you use, with each volumetric step, or tier, bringing you a higher rate - a TOU rate does not increase on volume but on the time of day.  As a result, rates during peak periods can be 50% or more higher than the lowest periods.  Of course, that peak period - either 4-9 or 5-8 with SCE - corresponds to when people generally use the most energy!  Gotcha!!! (Those rate differentials are what provide the economic benefit of adding storage, and make simple strategies - like delaying the dishwasher or EV charging until out of peak rates - effective at saving money.)

How is SCE’s TOU Rate Changing?

Needless to say, SCE’s rates are very complex, with the energy charge being comprised of some eleven different components!  I will spare you those distressing details and just focus on the overall energy charge and how it has changed, as shown in this table:

SCE’s TOU-D Rate change for the 4-9 p.m. option.

On average, we see that rates here have increased between 3.67 and 3.80% over the prior rate, but there are some special gifts to solar customers buried in the rates.  When the Net Metering rules were changed a few years ago, it introduced the concept of Non-Bypassable Charges (or NBCs) - components of the rate structure that solar customers paid for every killowatt hour pulled from the grid, even if that same kWh was netted back by energy exported to the grid.  Far and away the largest NBC is the Public Purpose Programs charge, and in this rate increase it jumped from 1.323¢/kWh to 1.622¢/kWh - a whopping 22.6% increase! 

Another fun fact for SCE customers who have endured so called public-safety shutdowns, is that they are paying 0.6¢/kWh toward the “wildfire fund charge"!  That’s right, SCE’s customers are helping to pay for an insurance fund against wildfires caused by SCE, PG&E, and SDG&E - now isn’t that almost enough to get one hot enough to, well, burn!

Use Case Impacts

We decided to examine how potential clients would see their bills, and potential savings, change under the new rate structure.  As always, we made use of the wonderful tool Energy Toolbase to do our calculations. 

Our first example is a pretty average user in the Run on Sun service area, consuming approximately 30 kWh of energy per day, pre-solar.  Under the old TOU rate their annual bill pre-solar was $2,946, but under the new rate (including things like utility user taxes, etc.) their bill would go up by nearly 5%, an extra $144 for the year.  However, their post-solar savings also increase, by 5.42% or an extra $143 per year.  For this average user, adding solar ended up being a nearly perfect hedge against the SCE rate increase!

Our second user does not fare quite as well.  This is a significantly larger user, consuming more than 50 kWh/day.  Their pre-solar bill increases by 4.29%, or $228. Unfortunately, while their overall savings increases, it is not as dramatic as it is for the smaller user, reducing the differential from $228 to $92, compared to reducing it to just $1 for the average user.

Bottom line - adding solar helps hedge against rate increases, and as energy costs get higher, your annual savings will increase!

Meanwhile, SCE is Trying to Kill Rooftop Solar

It is one thing for SCE to be seeking, and getting, rate increases from the CPUC - that is their business model.  It is quite another thing for them to try and gut the value of net metering, thereby eliminating the economic value of adding solar - but that is precisely what they are trying to do!  We are fighting back, starting with a signature campaign targeted at a petition to Governor Newsom. 

There will be lots more to do in the coming days to fight against SCE’s attack on solar, but for now there is something simple that you can do - mash that button below and go sign the petition!