California has enough clean, renewable energy to replace the power from the Diablo Canyon Power Plant several times over, but the California Public Utilities Commission (CPUC) doesn’t know it.
Rather, the CPUC is in the grip of the idea that California must keep the Diablo Canyon Power Plant operating for five or 20 years beyond its previously scheduled closure because we won’t have enough renewable energy on hand to replace the power output of Diablo before it shuts down. This received wisdom has been widely disseminated, but it’s not true.
Here’s why that matters. Senate Bill 846 was passed in the final minutes of the legislative session based on that premise. But legislators included a condition in the bill: “If the [California Public Utilities] Commission determines that new renewable energy and zero-carbon resources that are adequate to substitute for the Diablo Canyon Power Plant and that meet the state’s planning standards for energy reliability have already been constructed and interconnected by the time of its decision, the commission may issue an order that reestablishes the current expiration dates as the retirement date, or that establishes new [earlier] retirement dates.”
The CPUC has now released a proposed decision, which notes that SB 846 “limits the commission’s consideration of reliability issues in this proceeding to renewable and zero-carbon resources that ‘have already been constructed and interconnected’ by the end of 2023.”
There are two problems with that: The proposed decision was issued on Oct. 26, more than two months before the end of 2023, and the most recent reports it cites are from May 2023, covering the period January through March.
So you can’t really blame it for not including a statement issued by Gov. Gavin Newsom’s office on Oct. 24.
The assessment of the governor’s office is clear: In just the last three years, PG&E, Southern California Edison and San Diego Gas and Electric have put 4,992 megawatts of battery storage online. Another 1,900 MW of energy storage projects are expected to be online by the end of 2023. All told, that’s more than three times the generating capacity of Diablo Canyon.
The governor’s office is not alone in discovering the good news. Energy consultant Robert Freehling has crunched the numbers from the California Energy Storage System Survey, the California Independent System Operator’s “Key Statistics” report for September 2023, and the September edition of the U.S. Energy Information Administration’s monthly spreadsheet listing extensive data from all the power plants in the United States—i.e., more current data than what the CPUC relied on in its proposed decision. In summary, there appears to be between 5,900 to 6,700 MW of utility-scale batteries on the grid, plus 1,400 MW of customer batteries.
Freehling notes that citations of “new” utility-scale battery storage added to the grid as of May 2023 “is defined as built since January 2020, and therefore does not include batteries built before January 2020, nor new batteries built since May, nor does it include customer batteries. It turns out that the main report intended by the Legislature to be used for evaluating the need for Diablo Canyon has quite a lot of battery capacity that is omitted.”
The CPUC’s proposed decision repeatedly claims that an argument that “significant growth in installed energy storage and renewables … fails to demonstrate whether current projects installed are an adequate substitute for Diablo Canyon and meet the state’s planning standards.” By way of a reminder: It was the battery energy storage systems that were operational in the first week of September 2022—far fewer than will be operational by the end of 2023—that saved the state from blackouts when an epic heatwave should have made them inevitable. Was the energy resource that saved our butts an inadequate substitute for Diablo Canyon? Did it not meet the state’s planning standards? Or is the CPUC using those vague phrases from SB 846 as a talisman to ward off the obvious?
Extending Diablo Canyon’s life will cost California ratepayers at least $8.1 billion, unless it can be shown that the state will have enough renewable energy online by the end of 2023 to replace Diablo. How far could $8.1 billion go to solving our real climate and energy needs instead of propping up the dead-end technology of a 50-year-old nuclear reactor?
The commission could rule on the implementation of its proposed decision as early as its Nov. 30 meeting. To get the message to the CPUC and your state senator before that date, drop a note to CPUC commissioner Karen Douglas care of kourtney.vaccaro@cpuc.ca.gov, and to state Sen. John Laird at senator.laird@senate.ca.gov.
Let them know you don’t want to keep Diablo Canyon on life support with billions of taxpayer dollars when California’s clean energy generation has already left Diablo in the dust. Δ
Andrew Christie is the executive director of the Santa Lucia Chapter of the Sierra Club. Write a response for publication by emailing it to letters@newtimesslo.com.
This article appears in Holiday Guide 2023.
My math is different. I came up with 13,200MW of batteries with 4-hour ratings (if you had immaculate contracts and scheduling) to replace Diablo instead of the articles existing 5,900MW of batteries @ 4 hours. The industry picked 4 hour ratings as the battery measurement standard, since you cant discharge 24 hours without charging for half the time and there is transition time between charging and discharging where you can accomplish two charging and two discharge sessions each day.
The author of the article neglects the power equation time factor and tries to compare 24/7 generation and 4 hour rated batteries. MW is an instantaneous measurement of electrical energy (work), whereas MWh is the measurement for Power. Batteries by industry convention and CPUC standard are rated for 4-hour periods. If lucky, a utility could discharge the 1-4 AM battery charge for 2 hours in the morning from 8-10AM (using Washington hydro, natural gas or Four Corners nuke depending upon season) and then charge batteries from Topaz/Carrizo Solar from 10-5PM to execute a full 4-hour discharge to meet the evening peak 5:30-9:30PM. So best case battery production is 6 hours x 5,900MWh = 35,400 MWh on a perfect day. If youve looked at the CAISO Todays Outlook-Supply tab-Renewal tab batteries are discharged on a bell curve with peak usage of ~2.5 hours. The more realistic battery discharge value of 4 hours x 5,000MWh = 20,000 MWh on an average discharge day is more likely in that with all the different battery entities having different contracts, its like herding cats compared to Diablo with stable contracts. Contrast those battery utilities with ~20,000MWh against base loaded Diablo U-1 & 2 at 24 hours x 2,200MWh = 52,800MWh. So, the current replacement value of all commercial batteries versus DCPP is 20,000/52.800= 0.378 or 38%. There must be scarcity for utility batteries to succeed as parasitic storage and net energy users.