CPUC approves Diablo Canyon retirement plan

California regulators have approved a proposal from Pacific Gas and Electric (PG&E) to retire the Diablo Canyon nuclear power plant when its operating licenses fully expire in 2025.

The California Public Utilities Commission (CPUC) today voted to retire the facility, the last operational nuclear power plant in California.

PG&E filed an application with the CPUC in August 2016, in which it proposed to retire the facility upon the expiration of its Nuclear Regulatory Commission (NRC) licenses.

Diablo Canyon is located in San Luis County and consists of two units. Unit 1 and Unit 2 have been operating since 1985 and 1986, respectively, and have a combined generation capacity of 2,240MW.

The units are licensed to operate until 2024 (Unit 1) and 2025 (Unit 2).

The company had found that in the near future, there would be significantly less need for electric generation from the Diablo Canyon facility. PG&E has also said that the retirement of the facility will not affect energy reliability.

According to Argus calculations, replacing Diablo Canyon's output would require 587mn cf/d (17mn m³/d) of natural gas.

PG&E's application also requested approval to procure resources to partially replace Diablo Canyon's output. PG&E had originally proposed a rate increase of $1.3bn to fund the procurement of energy-efficient resources to replace Diablo Canyon's output.

The CPUC rejected this proposal, citing that more investigation was needed in a separate proceeding.

The Integrated Resources Procurement proceeding is actively considering the optimal mix of resources needed to reduce the greenhouse gas emissions from the electric sector while maintaining reliability and minimizing costs to customers, the CPUC said.

The CPUC has approved PG&E to recover $222.6mn in rates for employee retention and training, and $18.6mn for its license renewal activities, plus a portion of the cost of cancelled capital projects.

Following the CPUC's decision, PG&E said it would confer with other groups involved in the proposal about how to move forward.

In November, an administrative law judge with the CPUC issued a proposed decision that would approve some elements of PG&E's application. The decision was not legally binding.