ERCOT unveils plans to improve Texas power grid reliability Source: Reuters After a rule change, ERCOT suggests power operators submit a letter signed by their CEOs twice a year certifying their companies have completed their weatherization preparations for the summer and winter seasons. A persistent extreme heat wave across the United States has strained power grid operators as residents have cranked up air conditioners. This follows a deep freeze in Texas that left millions without power for several days in February. ERCOT also proposed a new market rule that requires generators to provide operational updates more frequently and perform unannounced testing of generation resources.