It was 7:09 a.m. Jan. 28 when a Duke Energy Corp. dispatcher called PJM Interconnection LLC, the grid operator for 13 states in the Midwest and Mid-Atlantic. The Duke dispatcher said his boss, Greg Cecil, was on the line. He wanted to know whether PJM was going to call on the company's natural gas-fired Lee generating station near Chicago to operate that day. Cecil, managing director of generation dispatch and logistics for Duke's Midwest commercial generation unit, isn't usually involved in this level of conversation. But this was different. A day earlier PJM had told Duke to have the plant ready to run. Much of the eastern half of the nation was in the grips of an Arctic blast. Record demand was anticipated, and the grid operator was doing everything in its power to keep the lights on.