California conquers summer heat

California suffered a heat wave in late August and early September, but unlike in the days of the California Energy Crisis of 2000 and 2001, there was no need for rolling blackouts. The California Independent System Operator (ISO), which operates the state’s electrical grid, credited energy consumers with averting a crisis through their electrical conservation efforts. Officials with the California ISO estimate that on Aug. 30, Californians reduced their electrical demand by about 1,000 MW, helping to avoid overtaxing the state’s transmission grid.

The next day saw a peak demand of 48,615 MW, the highest demand for power of the summer, but the ISO was able to meet the demand with sufficient operating reserves. Power outages only occurred at local levels and were caused by power distribution systems, not by the transmission system.

By the third day, with cooler temperatures in Northern California, the statewide power grid was in good shape.

At no time during the heat wave was there an imminent threat of a Stage Three electrical emergency—rotating blackouts—on the high-voltage grid, said California ISO officials.

California’s power crunch this past summer was caused by a heat wave that affected much of the Southwest, reducing power imports into the state. In addition, the previous winter was dry, reducing summer hydropower generation by about 1,000 MW.