PG&E Corporate Responsibility and Sustainability Report 2021

COVID-19 Response

Nuclear Operations

PG&E’s Diablo Canyon Power Plant generates safe, clean, affordable and reliable carbon-free energy to meet the needs of more than 3 million Californians.

Our Approach

While Diablo Canyon’s Units 1 and 2 will close in 2024 and 2025, respectively, we remain strongly committed to the highest levels of safety, performance and security at the facility. The Nuclear Regulatory Commission’s (NRC) latest annual assessment of the facility places Diablo Canyon among the highest-performing plants in the U.S. nuclear industry. This reflects the hard work and dedication of our coworkers and our commitment to meeting PG&E’s and the NRC’s high-performance standards.

Spent Fuel Storage

At both Diablo Canyon and PG&E’s former nuclear unit at the Humboldt Bay Power Plant, PG&E safely stores spent fuel in on-site dry cask storage systems approved and licensed by the NRC. Diablo Canyon also safely and securely stores spent fuel in a wet storage facility. These two on-site interim storage solutions are federally monitored and follow industry best standards to ensure that they are safe and effective.

Water Management

PG&E actively manages the water used in the electric generation process in accordance with the water discharge limit set by Diablo Canyon’s Clean Water Act permit.

2020 Milestones

In 2020, Diablo Canyon Unit 1 underwent a safe and successful refueling and maintenance outage. Unit 2 experienced several generator maintenance outages. Each unit produces 1,143 MW of greenhouse gas-free electricity into the energy grid during regular operations.

PG&E also continued decommissioning the former nuclear unit at the Humboldt Bay Power Plant, where site restoration and remediation efforts are in the final phase.

Measuring Progress

Diablo Canyon continues to demonstrate high operational performance as gauged by its plant capacity factor, a measure of generation reliability. Despite being a year when Unit 1 underwent a planned refueling outage and Unit 2 had three maintenance outages, Diablo Canyon achieved a capacity factor of 83% during 2020.

Nuclear Power Plant Performance
Average Capacity Factor Footnote 1
2016 96%
2017 91%
2018 93%
2019 83%
2020 83% Footnote 2
  • 1. Refers to the ratio of the actual output of the plant relative to the output if the plant had operated at full capacity for the year.1
  • 2. In 2020, Unit 1 underwent a planned refueling outage, which occurs approximately every 18 months. Additionally, Unit 2 had three generator maintenance outages that, combined, lasted more than 80 days.2