California Avoids Blackouts Despite Heat Wave, Nuclear Outage

The California power grid avoided problems earlier this week despite a heat wave and a nuclear plant outage.

The state’s biggest nuclear plant, PG&E’s 1,122- MW Diablo Canyon Power Plant (pictured), shut down on June 27 before the heat wave started, resuming activity just prior to peak load on July 2 as the temperatures started to cool, Reuters reports.

In response to the high temperatures and the Diablo rector shutting down, the California ISO issued a “flex alert” for July 1-2, asking power customers in Northern California to conserve power and help avoid blackouts. This was the ISO’s second flex alert in 2013, Reuters reports.

PG&E is the largest utility in in the state, providing natural gas and electric service to approximately 15 million people in northern and central California. The state’s other two big utilities — Southern California Edison, a unit of Edison International, and San Diego Gas and Electric, a unit of Sempra Energy — serve the southern part of the state.

Reuters says power-generating resources in California are less than usual since the permanent closure of the San Onofre nuclear power plant in June.

North American reliability coordinators have warned that “operational challenges” could be in store for the state, following the shutdown of Southern California Edison’s San Onofre reactor, and that a prolonged heat wave could force utilities to use rolling blackouts in the San Diego and Los Angeles areas, Reuters reports.

ICF International also has forecast “significant transmission congestion” into Southern California this summer. The consulting and technology services company this week warned that system generator capacity will be greatly impacted as a result of the retirement of the San Onofre plant. With summer temperature predictions higher than average and the economy recovering, peak demand is expected to be 1.6 percent higher than in 2012, ICF International says.