California readies to prevent blackouts, but threats remain ADAM BEAM, Associated Press FacebookTwitterEmail FILE - In this Aug. 15, 2020, file photo, high voltage signs are posted on the Department of Water and Power Sub Station E in the North Hollywood section of Los Angeles. Last summer, an extreme heat wave across the United States increased demand for electricity so much that state officials had to briefly turn off the power for hundreds of thousands of people. On Tuesday, May 18, 2021, the state's top energy regulators told state lawmakers they are better prepared for a similar scenario this year. But they said they could not guarantee rolling blackouts would not happen again.Richard Vogel/AP