Your Neighbor's Solar Panels Are Secretly Saving You Money

We are, admittedly, geeks; Popular Mechanics is cool. Therein, an article this month engages the value of solar, beyond the obvious utility savings. Thesis:

There’s a persistent myth that says houses with solar panels could raise energy costs for their neighbors. But a new analysis puts that notion to bed, showing that solar panels actually drop the cost of power, even for nearby houses.

How’s that? Scientists say solar panels lower peak demand on stressed traditional grids and have reduced the amount of infrastructure dollars that energy utilities must invest. By hooking your solar panels to the grid, you’re sneakily a hands-on investor in your local utilities.

The perpetual tug-of-war between the solar industry and utilities (and their regulators) sees and saws on the cost (or, positively, value) of residential solar systems. The Popular Mechanics piece references a study cited in the March issue of Renewable and Sustainable Energy Reviews. Instead of solar panels increasing the cost of electricity for homes without solar, the reverse is true (through the financial lens of utilities): Homes with solar panels greatly subsidize local electrical grids.

The researchers broke down the “value of solar,” assessing variables (i.e., avoided costs to utilities) like plant O&M [operation & management] fixed and variable; fuel; generation capacity, reserve capacity, transmission capacity, distribution capacity, and environmental and health liability. The results:

… grid-tied utility customers are being grossly under-compensated in most of the U.S. as the value of solar eclipses the net metering rate as well as two-tiered rates.

One additional thought: A community’s energy resilience improves as its distributed generation network (grid-connected solar systems) grows. In simple terms, communities in Yolo County are less dependent on the grid given the abundance of local solar systems. When demand for electricity peaks — think of August/September last year — we have a vast array of homes producing their own power (including nearly one-in-three in Davis). Hence, we are less susceptible to brown outs, and we make PG&E’s job easier (and less expensive).

Let Yolo shine.

The power is out. I want a battery. (Or, do I?) 2021 thoughts on solar-tied storage.

[Photo courtesy of the great Owen Yancher @davisenterprise.com]

This is a bit of a reprise from last year, wherein we shared thoughts about the pros and cons of purchasing a solar-tied battery. Then and now, our position is constant: We do not believe it makes economic sense. But, we do do it (install batteries).

Since the two-week-ago storm, we’ve fielded several dozen calls from local homeowners, all seeking the peace-of-mind of reliable electricity. Completely understood: My wife and I lost our power, in Willowbank, for about 36 hours, and my partner’s power was out for five days. No bueno.

It was an extraordinary storm, and our collective response, rightfully so, was extraordinary.

Pragmatically, we continue to dissuade homeowners from investing in batteries: They’re expensive (about $13,000, pre-tax credit, for a 10 kW battery that will power a handful of low voltage circuits during an outage) and the net-metering arbitrage is insulting ($50-100/year in benefit).

But, if energy security and resiliency is important, batteries are worthy of consideration. They work, they’re proven, and they are getting better. Here’s an email we received from a Repower client (for whom we installed an LG solar and battery system, in concert with SolarEdge’s kick ass Energy Hub inverter and power optimizers):

I thought I'd write you a brief note about our system. As you all are probably aware, there have been a few outages in Yolo county the past 2-3 days and we were not spared in it. Our power went out at 4pm on 1/28 and restarted at 9pm that night. Our batteries kicked in 2 seconds after the outage started and continued until the outage was over. We were able to keep our internet access until about 7pm when ATT broadband went down, but we had cellular service. It was eerie in how dark and quiet our neighborhood was, yet our place was lit up like a cheap Las Vegas casino.

Since this was our first real outage and we were skeptical as to PGE's estimated restoration time, (in addition to standing out like a sore thumb amongst our neighbors), we turned off unnecessary lights and tried to conserve. By the time the grid was back up, we had 88% battery capacity left and everything worked as planned.

This morning I've been fielding a few inquiries from our neighbors who want to know more about our batteries! Our batteries are recharged back to 100% and things are humming along.

Thanks again for everything that you've done to make this possible.

We are very pleased with the outcome!

We cannot quantify nor arbiter the value of security. Of course, if given the choice, nary a homeowner would opt to live in the dark. But, if the trade off is investing $10-20k versus enduring a power outage (or, employing the analog: a generator), we believe it’s worthy of considering the pros and cons.

An anecdote: We’ve had several prospective Repower clients share that solar companies told them they would “throw in a battery” to their solar system purchase. Nothing is thrown in; homeowners pay for it. Don’t fall for the sales ploy.

As we opined in July 2020, solar + storage is the future: "Homeowners no longer take their electricity security for granted. They are increasingly anxious about maintaining normalcy as supply uncertainty increases.”

Storms are one thing. PG&E brownouts — when peak demand exceeds electricity supply — are another. Fortunately, residents in suburban Yolo County are fairly immune from PG&E’s shut downs: We are surrounded by a (wonderful) agricultural buffer, and more than 25% of homes in our community have solar PV systems, thus lessening our reliance on the grid. We are a resilient community, sans storms.

Then and now, we’re happy to help homeowners evaluate whether batteries (and solar, of course) make sense. We commit to maintaining our objectivity and will endeavor to be less pessimistic, opening our minds to the subjective rationale of adding storage to a solar system.

Please contact us if you’d like to learn more. Until then, our best to you and yours … we will get through this pandemic, stronger and more resilient on the other side.

PG&E's EV rate with solar: No bueno

In October 2019, PG&E disseminated a rosy communique to homeowners who were enrolled in their “EV-A” electric vehicle rate schedule. The letter trumpeted the benefits of their new (“EV-2”) rate schedule: Extended off-peak period, lower peak rates, the world’s now a better place … all thanks to Pacific Gas & Electric Co.

Approximately one-third of homeowners Repower has helped go solar own, or plan to acquire, an electric vehicle. And, why not? If your amortized cost to generate solar electricity is ~8 cents/kWh and you garner four miles of range per kWh, driving via sunshine (trite!) is beyond cheap, let alone ecologically awesome.

Background: In February 2019 we encapsulated and quantified the benefits of PG&E’s “EV-A” rate schedule in a blog post, specifically for homeowners who enjoyed solar and drove electric vehicles. In short, under EV-A there was a good degree of arbitrage for solar+EV owners: If you played the game, your solar system only needed to generate ~75% of the electricity you consumed to, at annual net-metering true-up, zero out your bill. This was accomplished by shifting your electrical loads — charging your car, doing laundry, running your pool pump — to off-peak periods, when electricity was valued at ~13 cents/kWh. Conversely, if your solar generation exceeded your household electricity use during peak period (2-9 p.m., Monday-Friday), you racked up credits at 45-50 cents/kWh. Simple and viable.

Today, PG&E’s electric vehicle rate schedule (EV-2) is not viable. (Side note: EV owners who enrolled in the original, EV-A, rate schedule prior to October 2019 were grandfathered in for five years, commencing the date you enrolled; such homeowners will be transitioned to EV-2 after five years.)

The net-metering calcs are stark, when contrasting three PGE time-of-use rate schedules: EV-A, EV-2 and TOU-C (PGE’s de-facto time-of-use rate schedule, whether you do or do not own an EV). The below examples are actual net-metering data from a Repower homeowner who purchased an EV (after going solar). At annual true-up, they consumed 2,157 kWh more than their solar system generated. They charged their car and did laundry at night, and programmed their pool pump to run during off-peak periods too.

First, annual metrics for a solar + EV homeowner under the original EV-A rate schedule:

Next, here’s the same homeowner under EV-2:

And, here are the results if the homeowner enrolled in TOU-C:

Same electricity use pattern, same solar generation profile, three different annual financial results: 

- EV-A: $211

- EV-2: $959

- TOU-C: $623

Hence, since EV-A is not available, this electric vehicle-owning homeowner should enroll in TOU-C (and, thereby, save $336/year versus EV-2). If the homeowner had been enrolled in EV-A and was then switched, automatically by PG&E, to EV-2, their annual electricity costs would have increased $748. Ouch.

PG&E can be a pain in the posterior, particularly if you endeavor to keep up with their always changing rate schedules, time-of-use periods, and rates. If you are considering solar — and own or are contemplating an EV — feel free to contact us to receive a no-cost analysis of your net-metering options.