Sweltering heat tests Texas' power grid and patience as thousands in South still without electricity

Texas’ power grid operator is asking residents to voluntarily cut back on electricity due to anticipated record demand on the system as a heat wave keeps parts of the state and southern U.S. in triple-digit temperatures. Much of Texas on Tuesday was under excessive heat warnings. In the West Texas city of San Angelo, temperatures soared to an all-time high of 114 degrees. The Electric Reliability Council of Texas' request is its first this year asking customers to curtail their energy use. In neighboring Oklahoma, meanwhile, more than 100,000 customers are eagerly awaiting the restoration of power following weekend storms. And in Louisiana, more than 51,000 electricity customers are still without power.