As a massive winter storm barrels across the U.S., power grid operators are taking extraordinary steps to keep the lights on and avoid rolling blackouts. The storm, stretching more than 2,300 miles, has triggered sharp price volatility in electricity markets and forced some regions to temporarily lean on oil-fired generation to meet demand, Reuters reported.PJM Interconnection, the nation’s largest regional power grid serving 67 million people across the East and Mid-Atlantic, saw wholesale electricity prices…