California Report on Blackouts Blames Climate Change and Planning

A report by California energy officials on Tuesday placed blame for rolling blackouts that left millions without power in August on the impact of climate change and outdated policies and practices that failed to adequately take into account hotter weather.

In the 121-page preliminary report to Gov. Gavin Newsom, the state’s three central energy organizations attributed the blackouts — the first in two decades — to a heat wave that increased demand for electricity while reducing the supply of power. Poor planning compounded those problems, according to the report, which was produced by the California Energy Commission, the California Public Utilities Commission and the California Independent System Operator.

“The combination of these factors was an extraordinary event,” the agencies said in the report. “But it is our responsibility and intent to plan for such events, which are becoming increasingly common in a world rapidly being impacted by climate change.”

As triple-digit temperatures blanketed the West on Aug. 14 and 15, the California I.S.O., which manages the power grid for 80 percent of the state, ordered utilities like Pacific Gas & Electric and Southern California Edison to black out as many as 3.3 million customers to reduce demand for electricity.