The operator of the state's electricity grid is asking Texans to conserve power this weekend, after six generation plants went offline Friday amid unseasonably hot weather. Thermostats should be set to 78 degrees or higher, and people should avoid "the usage of large appliances," such as dishwashers, washers and dryers, from 3 p.m. to 8 p.m. through Sunday, the Electric Reliability Council of Texas said in a statement that was released shortly after 5 p.m. Friday.