Nuclear Energy in California

Andrew Liang
February 15, 2017

Submitted as coursework for PH241, Stanford University, Winter 2017


Fig. 1: Santa Susana Sodium Reactor Experiment. (Courtesy of the DOE)

California is considered one of the pioneers of nuclear power. It was the first state to adopt nuclear energy as a commercially viable means to provide the public with electricity through the Santa Susana Sodium Reactor Experiment in 1957. Since then, a total of 5 more nuclear plants have been built with only one, Diablo Canyon, currently left in operation. In 2010, nuclear provided approximately 16% of all electricity while being the third largest energy source for the state. [1]

Santa Susana Sodium Reactor Experiment

Considered the first nuclear power plant to provide the public with electricity, Santa Susana Sodium Reactor Experiment (SRE) was built in 1957 (Fig. 1). Located in Ventura County, it produced a maximum of approximately 20 megawatts and was cooled via sodium. In 1959, the power plant suffered a partial core meltdown where almost one-third of the fuel assemblies were damaged and subsequently released an unidentified amount of radiation into the atmosphere. [2] The SRE meltdown is often not brought up in significant nuclear meltdown discussions due to corporate and governmental secrecy. The power plant was closed for good by 1964.

Fig. 2: Diablo Canyon. (Source: Wikimedia Commons)

Diablo Canyon

Open since 1985, the Diablo Canyon nuclear power plant (Fig. 2), located near San Luis Obispo and owned by PG&E, is the last remaining operating power plant in the state of California. In stark contrast to SRE, Diablo Canyon can produce a combined 2160 megawatts between its two units and is cooled via ocean water. [3]

Despite being able to produce enough energy to meet the needs of more than three million Northern and Central Californians, Diablo Canyon's two units will be shut down by August 2025 after its operation license expires. [4] Diablo Canyon's electricity output will no longer be needed as PG&E attempts hone in on the California mandate stating that half of the state's electricity generation be through renewable resources by 2030.[3]

© Andrew Liang. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.


[1] "State Nuclear Profiles 2010," U.S. Energy Information Administration, April 2012, p. 7.

[2] R. L. Ashley et al., "SRE Fuel Element Damage Final Report," Atomics International, NAA-SR-488 (suppl.), 1961.

[3] I. Penn and S. Masunaga, "PG&E to Close Diablo Canyon, California's Last Nuclear Power Plant," Los Angeles Times, 21 Jun 16.

[4] P. Mayeda and K. Riener, "Economic Benefits of Diablo Canyon Power Plant," Pacific Gas and Electric Company, June 2013.