In summary

Nuclear power peddlers are blaming the state’s shift to renewable energy for power outages to justify keeping the Diablo Canyon Power Plant open. This is a false narrative.

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By Robert Freehling, Special to CalMatters

Robert Freehling is an independent consultant who focuses on state and local clean energy policies.

As summer temperatures rise, Gov. Gavin Newsom is running scared of the kind of power outages that could bring down a governor. His remedy — to extend the operation of the Diablo Canyon Power Plant past its 2025 scheduled decommissioning date — is misaligned with California’s energy challenges. 

Not only is 2025 three years too late for this summer, but more than 4,000 new megawatts of reliable power capacity have been added to the state’s power grid — the equivalent of two Diablo Canyons. In addition, according to the state Department of Finance, there are nearly 1 million fewer people in California today than state energy planners forecast

Newsom has reached for the wrong tool to assuage his fears of a repeat of August 2020 power outages, when nearly 500,000 households — a little over 1% of the entire state — lost power for about 1.5 hours. 

Nuclear plants supplying electricity to California were online during the early 2000s energy crisis and in 2020. They did not prevent outages. 

In fact, Diablo Canyon was identified as one of the major contributing factors to the 2020 outage. Federal and Western regional regulations require the California grid operator, known as the California Independent System Operator, or CAISO, to maintain 6% reserve margins at all times, adequate to cover the threat of loss of the largest power generator and transmission line on the grid. Diablo Canyon cannot be part of that reserve because it already is generating power. Nuclear plants run 24/7 year-round; for safety reasons, they do not respond to sudden increases in demand or loss of other power plants on the grid.

If Diablo fails, it could result in “destabilizing the greater western grid,” according to the official report on the causes of the 2020 power outage. To maintain the reserve, the grid operator had called for rotating outages. In effect, customer power outages were used to “back up” the nuclear plant — the grid operator could not trust Diablo Canyon to continue operating reliably for just one and a half hours.

As the largest electric generator in California, Diablo Canyon is more of a liability than a supply source during times of stress. 

The leading causes of most power outages are problems with transmission and distribution lines — a branch falling or a fried squirrel, for example. In California, customers suffer purposeful shutoffs of power to prevent faulty wires from starting wildfires. Even 100 nuclear power plants wouldn’t prevent these outages.

Flaws in the independent system operator’s energy market also played a key role in the August 2020 power outages, just as they had 20 years earlier in the California energy crisis. Buried on page 113 of the Final Root Cause Analysis report, the grid operator admits that “Energy market practices contributed to the inability to obtain additional energy that could have alleviated the strained conditions on the CAISO grid on Aug. 14 and 15.” The report goes on to say that the independent system operator failed to properly forecast demand for the next day, and to schedule adequate power supply. The grid operator allowed the export of thousands of megawatts of power out of California, at the time it was most needed. This caused a scramble for power supplies, and for the independent system operator to call for a 1,000-megawatt outage on Aug. 14, and a 500-megawatt outage on Aug. 15. 

Flawed market operations created a supply-and-demand problem. 

Newsom, however, blamed the state’s shift to renewable resources as the cause of the supply shortage; the governor was alone among state officials making this claim. “Officials have consistently said that intermittent power sources such as solar panels and wind turbines didn’t cause the rolling blackouts,” according to the Los Angeles Times,

According to Rao Konidena, an independent energy consultant, renewables don’t cause blackouts. Stakeholders say the issue is more complicated.

Newsom and a new crop of nuclear power peddlers, however, including former gubernatorial candidate Michael Shellenberger and Jessica Lovering, executive director of a pro-nuclear think tank, are weaponizing power outages to justify keeping Diablo Canyon open. 

As they plan for the future, Newsom and the pro-nuclear pushers should stop promoting Diablo Canyon as California’s energy savior, acknowledge what really caused the August 2020 power shortages, and understand the real solutions.


Read an opposing viewpoint on this topic here.

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