REC Coop to Invest in Battery Storage

A battery storage facility: not nearly as photogenic as solar panels and wind turbines

by James A. Bacon

Rappahannock Electric Cooperative (REC) is partnering with Charlottesville-based East Point Energy to install the first grid-scale battery-storage project by a Virginia electric cooperative.

The project has a peak capacity of two megawatts and a duration of eight megawatt hours, enough to power about 1,000 homes for eight hours, the coop stated in a press release two days ago. REC provides electricity to 170,000 connections in portions of 22 Virginia counties.

There has been much discussion about large-scale battery storage as a supplement to solar and wind power as Virginia moves to a carbon-free grid by 2050. In theory, batteries will be able to store excess electricity generated by the intermittent power sources and release it when the weather isn’t cooperating. But the aim of the REC energy-storage project, to be located in Spotsylvania County, is more modest. Anticipated benefits include:

  • Temporarily providing electricity at times when the transmission system fails and coop members would otherwise be without power.
  • Managing wholesale power costs by dispatching stored energy during peak times when electricity is more expensive for the cooperative to purchase.
  • Delaying the need for substation upgrades.

These are tangible benefits with a measurable monetary value that will help REC’s electric distribution system work more reliably. REC provided no numbers, however, to indicate the size of the financial investment or the expected return on investment.

By way of comparison, Dominion Energy received State Corporation Commission approval earlier this year to build 16 megawatts of battery-storage for $33 million in four pilot projects. (Assuming a comparable cost per megawatt, REC’s investment should be in the realm of $4 million.) Dominion hopes to understand how best to deploy the batteries to work in concert with variable solar energy generation.

Bacon’s bottom line: It’s one thing to use batteries to help offset the fluctuations in intermittent power generation as clouds pass over solar farms or winds gust through wind farms. The ability of batteries to instantaneously release electricity into the grid upon command will help regulate grid voltage and frequency, which must be kept within tight parameters. That is a high-value use, and it justifies spending the high cost of the batteries.

That’s a much smaller scale of deployment, however, than using electric batteries to store energy for the purpose of meeting daily and seasonal shifts in electric load — say, to store excess solar power generated at noon to continue providing electricity at 6 p.m. when the sun goes down.

Let’s use the REC numbers as a basis for analysis: an estimated $4 million to provide eight hours of electric power to 1,000 homes. Virginia had 3.1 million households in 2019. To build enough battery storage capacity to power every household after solar panels ceased generating electricity would cost about $12.4 billion. That’s just to supply homes, not businesses, and it assumes the sun shines every day without interruption. Factor in several days’ worth of cloudy weather and low solar output, and the need for additional battery storage increases exponentially.

The last thing we need is for Virginia to find itself in a situation similar to California where the headlong rush to a 100% carbon-free future has resulted in rolling blackouts across the state. California’s predicament was fully foreseen and fully man-made. Under state law, Dominion has 15 years to build a zero-carbon system, and Appalachian Power has 20 years. Battery storage will be an inevitable part of the solution. Hopefully the cost will decline in the years ahead, making it more economical to deploy. We don’t know how fast the price will come down, however, which makes the 15-year and 20-year conversion mandates totally arbitrary.

But it makes perfect sense right in the meantime to invest in pilot projects to learn more about how to integrate batteries into the grid.

There are currently no comments highlighted.

45 responses to “REC Coop to Invest in Battery Storage

  1. Interesting, and let’s hope it proves successful. Basically an 8 hour battery for a small town or some large subdivisions, in this case totally paid for by the coop members and it it proves successful, they reap 100% of the benefits. That will not be the case with an investor owned utility with frozen rates that will pass operational savings onto stockholders. We’ll just provide 100% of the cost.

    More and more coming out in California, including from Gov. Newsome, admitting their problem is due to too much reliance on solar and the off-lining of more reliable generation. A cautionary tale.

    • A good idea, but the largest issue would be the assumptions on required power. They could do a study over a year period and determine the average power requirements and size the batteries given that, but it doesn’t assume anything than a fudge factor. So it’ll be best guess of what’s needed.

      That’s one of the most obvious problems with batteries, they have a finite supply that needs to be replenished via other means. If those means are solar you have a window of time when that can take place and you also have to account for the DC to AC conversion factor (~98% efficient). Now you can size up, but to what level. Do you calculate for a 50% contingent or higher? What is the life cycle of the battery, what are the weather conditions and how will they hinder the batteries supply. Beyond that you’d have to account for losses in transmission. I’m assuming given the size it wouldn’t be prudent to be very close.

      It’s obviously a hefty investment that should take lots of studies to determine the proper amount.

  2. Said this before but calf.’s are not due to the “headlong” rush to renewables. Did’t you see Larry’s generation mix chart. Do you want me to draw you a picture? Ha!

    • Wow, so much to unpack that none of you who viewed that graph seemed to understand. Which is very curious given your professed credentials regarding the Energy sector. I’ll go one step further and site the actual data, not a pie graph without citation.

      https://www.energy.ca.gov/data-reports/energy-almanac/california-electricity-data/2018-total-system-electric-generation

      I’ll display them by deceasing values:
      1) Natural Gas – CA generates 46.54% of it’s power via NG, they however sell ~12% of that power to other parties as it’s excess. The CA power mix, mind you this was 2018 was ~34.91%.
      2) Renewable – CA generates 32.35% of it’s power via Renewable sources, which is a good thing. They sell around 1% of that energy to other parties.
      During the daytime hours the amount of energy supplied via this method is more than adequate. The problem arises when the temps don’t decrease and the sun goes down. Without any semblance of wind, windmills don’t turn and without the sun solar panels deplete rapidly when everyone is trying to chill their houses. Those two sources are the largest renewable sources used at ~11% respectively.

      Every other sources of energy production is less than 10% minus hydro. So if you assume that at 100% the system is maxed, which is how it’s designed you have to do the math following that.

      100%-(11.46+11.40) that places the system at capable of supplying 77.14% of the required load. So do you require a chart on why that isn’t a sustainable model?

      While being lauded for renewable source usage, they are placing too much of the load on systems that only generate during specific windows.

      Also, I’m going to be a petulant ahole, because well frankly ya’ll pontificate from points of zero authority.

      • That chart you linked to does not, in my reading, validate your statement that California “sells ~12% of [natural gas] power to other parties as it’s excess.” Total NG generation in California was 90,691 GWh; total NG consumption in the Energy Mix was 99,644 GWh, which means rather that selling NG as “excess,” CA was importing about 10% of NG generated energy into the state, as indeed, the chart also shows: 8,904 GWh from Southwest and 49 GWh from Northwest. From all sources, CA imported about 90,000 GWh of energy, as shown in the Total line. CA has long been an importer of energy.

        • My mistake I was reading several articles at ones on the topic. CA does in fact sell excess energy to other states. Thanks for pointing out my error.

          https://www.latimes.com/environment/story/2020-08-17/public-utilities-commission-to-blame-for-blackouts-caiso-says

          They are also listed as one of the top five states for importation of power ironically. The point of my comment was that they’ve set themselves up for failure with the way they provide their energy.

          The mix is to dependent on solar and wind, which both require specific conditions to generate. They also don’t tolerate natural disasters and prolonged temperature extremes (well the latter more the citizens).

          The link I gave said that they were going to try and shift more emergency generation to large hydro. I don’t know if that hasn’t taken place or what is going on but a 2700 Mw shortfall daily, is significant. it’s something that they need to figure out very quickly.

        • I wonder if Rowinguy could or would explain how California’s grid operates compared to Virginias.

          There appears to be two entitles – the “independent” grid operator and the public services commission.

          From my reading – what I get is that California has relied on the ability to import power when they need it but the current heat wave extends all through the regional west and the sources they normally relied on during peak periods were already committed to other regional peak demand needs.

          It sounded a little like if we had a huge heat wave in the East and PJM ran out of dispatch power because it was all committed.

          But as far as I know – this is PJMs bread and butter – this is what they do , i.e. plan for power needs – and grid reliability.

          Perhaps Rowinguy or TomH or others can explain it.

          • Larry, the CAISO is similar to PJM in our area; it dispatches power plants and operates the grid in California. Unlike PJM, it has only the one state to manage.

            I believe that all investor-owned electric companies in CA divested their generating units back in the late 90s and now must purchase all their power needs from the CAISO. There are numerous owners and marketers of generation selling into this market, both within and outside the state.

            The California Public Service Commission is sort of like the SCC here in Va, but to my knowledge, regulate only utilities in that state, not the broad array of authority the SCC has here. They set the retail rates for electricity, but do not set the price at which the utilities buy this power from the CAISO; per FERC that’s a market set rate.

          • Thanks rowinguy – I’m still not quite sure if PJM and CAISO are both apples or one is an apple and the other an orange and whether California’s problem is that CAISO does not operatelike PJM does or that if we had such a peak demand event that the same thing would happen to PJM.

            It comes across sounding like “someone” did not adequately plan for what happened .. or what happened was so extreme that it just overwhelmed – and it’s going to happen again.

            I think PJM came about for similar reasons way back when – we had a massive east coast blackout and PJM came into existence as a result.

          • Remember to throw into the mix that market manipulation is also responsible for shortages.

            Think Enron, and Ken Lay. Then pull the thread a little more and you find Enron also financing a chair poisition at UofMo.

          • Also keep in mind (last time I looked) Ca. imports a lot of hydro power from the federal-subsidized dams in PNW from out-of-state, Oregon, Washington, Hoover Dam in Las Vegas etc. So when we say Ca. exports excess power, I do not think we are saying *net* export of power, except possibly in certain times.

            When we talk about Ca. energy mix, and all states for that matter, we have to be careful to talk about overall (including out-of-state) vs. in-state boundaries generation.

          • TBill spot on, I believe CA exports solar power they have in excess when that occurs. I don’t believe I saw where they exported any other generation source.

    • Gavin missed Larry’s brilliant conribution, too….
      https://deadline.com/2020/08/governor-gavin-newsom-declares-statewide-emergency-fires-rolling-power-outages-1203016958/?mc_cid=acf180067b&mc_eid=2c7cec9efe

      Adams, pray tell, tells us what makes you the expert in this area. I know about TomH and Acbar, and I’ve spent some time on these issues.

      • I have an degree in EE. I also supplied the actual data and not a pie chart that is meaningless.

        The way to provide proper power, is the power mix. To much reliance on one source without the ability to cover that source is PM 101. In the end you need to =100% supply regardless of what’s happening. The consumer doesn’t care what issues you have within your system, they pay for a service to be provided. It ain’t a Government job, where you get paid to do nothing.

        I don’t claim to be an expert, I just don’t provide opinion without the data the back it up.

        • I have a question about something that is at least peripherally related to the topic at hand.

          What is your opinion on the potential for using super capacitors for energy storage?

          • I’m not familiar with “super capacitors” out of my preview. However, I’ve used them in wave rectifiers and or a car stereo or two in my youth.

            They are merely batteries without chemicals (in some instances and they have chemicals in others) and discharge more rapidly. Caps aren’t going to give you the tickle of energy a battery will until it depletes or drops below the threshold you require. You’d need a device or battery capable of absorbing that charge in a very short window.

            So if I’m understanding your statement you’d like to have a system with battery back up and a super cap back up for that battery? Both of which would charge during normal hours of ops for potential discharge when not in normal hours, thus potentially doubling your battery back up?

            My opinion in that respect would be how long can the battery maintain the depletion and rapid recharge before it fails. Would it merely cause a dead cell or would it cause catastrophic failure. For obvious reasons an instantaneous discharge wouldn’t do a lick for devices that didn’t have batteries.

          • Thanks.

            I’ve been seeing them mentioned as being used in some of the latest hybrid cars, and have been curious as to whether they could be scaled up for use as backup storage devices for solar and wind turbines.

            https://www.hybridcars.com/supercapacitor-breakthrough-allows-electric-vehicle-charging-in-seconds/

            https://electrek.co/2019/09/04/lamborghini-sian-supercar-supercapacitors/

          • I read where they we playing with replacing car batteries with a capacitor some years back. Guess they didn’t.

        • Thanks for the articles, it’s a very intriguing idea. I’d love to see how they extend the depletion time.

          Perhaps you could use regenerative breaking to charge the cap and allow it to discharge feeding the batteries. You could manage a smaller battery considering the efficiencies of the possible recharge.

          • “Perhaps you could use regenerative breaking to charge the cap and allow it to discharge feeding the batteries. You could manage a smaller battery considering the efficiencies of the possible recharge.”

            Formula 1 cars are already doing that. 🙂

          • Well I guess I’m not as dumb as NN and Larry seemed to believe I am, since I was able to formulate a notion that is being employed at the formula 1 level.

            I think the major difference there would be, those cars are probably getting new batteries every race.

          • “I think the major difference there would be, those cars are probably getting new batteries every race.”

            I’m not sure about it, but they may not get new batteries each race. F1 in the hybrid era has strict rules regarding how many power units and how many gear boxes a team may use over the course of a season, with major grid-place penalties for having to use additional units and/or for changing certain equipment out of a set schedule. I’ll look into it and see if batteries are included in the list of restricted items.

          • They are allowed 4 battery changes per season that roughly every 5th race. I looked it up and did some quick math, given that a race on average is 90 minutes, I don’t think that the hybrid nature of it would be terribly taxing. However, like I said before it would depend on the cap discharge rate and how much.

          • So I did some digging Wayne, as I don’t follow formula 1. It appears the battery was abandoned with the KERS system in 2014, which used the regenerative breaking to charge the battery for key points usage.

            Here is a link to SAFT which better describes what the new system does. My take is they are using super caps to give that 30 second boost, so 30 seconds is 5T. Where t is the time constants.

            https://www.saftbatteries.com/media-resources/our-stories/winning-race-power-formula-1-cars#:~:text=Regulations%20specify%20limits%2C%20such%20as,soon%20be%20cut%20to%20two.

          • Yes. I suspect the “Energy Store” being used with the current ERS (which replaced KERS in 2014) is actually a super capacitor rather than a battery. here is a link to another article which covers some of the changes which will be made to the rules for 2021.

            https://www.autoevolution.com/news/formula-1-energy-recovery-system-explained-125488.html

      • “On Saturday night,” said Berberich, “we were within an hour of being able to service the load without incident…We lost a 400 MW [power station] unit and, the wind had been every good, but ran out. If the wind hadn’t run out on us, we would have been ok.

        Sounds like an over-reliance on renewables to me. Exacerbated by other factors but as Berberich said, “If the wind hadn’t run out on us, we would have been ok.”

    • You can also use MAdams’ linked page to go back and look at 5 years of generation mix history in CA. In the latest year (2018) renewables account for about 32% of in-state generation. Five years ago (2014) it was just under 23%. So there has been a steady increase in this component of the generation mix. Is that “headlong” or “measured?” Most all of this growth appears to be in solar facilities, likely utility scale, and the operating characteristics of this block of power have indeed caused dispatch difficulties for the CAISO, the infamous “duck curve,” where output ramps up faster than demand in the morning and drops off faster than demand in the evening.

      Of course, CA is now experiencing one of the most prolonged heat events in history, with the hottest terrestrial temperature ever recorded occurring a couple of days back. Nevertheless, the system operator should have had resources available with which to manage it, with available reserves. I expect we may not know the reasons for these rolling blackouts for quite some time yet.

  3. Glad to see this in the national media yesterday. We need to do more of this.

  4. “Did’t you see Larry’s generation mix chart. Do you want me to draw you a picture? ”

    Har! Humor. Chart, picture, I get it.

    ‘Lectricity don’t care where it comes from. It’s all the same stuff in one of two transmission flavors. Coal, natural gas, nuke, solar, wind, everyone benefits with batteries in the mix. Maybe the folks at Smith Mountain could do without them because, in essence, they have a really big one. They keep fish in it.

  5. An interesting project. I hope it is successful.

  6. Hard to keep the boogeymen under control! We started off with “renewables are not reliable” to “storage is too expensive” to California , the 5th biggest economy in the world, is going belly-up because of too much reliance on renewables and worse… Virginia is following in their footsteps.

    gawd!

  7. It really is an insane asylum. Hey, did you see the news about Bannon? Is anyone keeping score? The boogeymen?

  8. This is my fault but I got off the dime. Batteries will be saviors. Must follow tech. Everyone benefits.

  9. Please look at what’s happening in California right now and see the You Tubes on why wind and solar are disliked by many clean energy people.
    Noisy, unreliable, disruptive to the environment, sometimes kill endangered species and cost to much per kwh. Nuclear as France has proven is the way to go, Germany and others in Europe are now realizing.

Leave a Reply