Solar panels and wind turbines get a lot of attention, but a more inconspicuous instrument is helping to reshape America’s energy economy right now: The humble light bulb. Over the past decade, traditional incandescent bulbs, those distinctive glass orbs with glowing wire centers, have been rapidly replaced by more energy-efficient lighting. The shift has driven down electricity demand in American homes, saving consumers money and cutting greenhouse gas emissions. The energy savings are expected to grow as highly efficient and increasingly inexpensive LED bulbs continue to replace older lights. But energy efficiency advocates worry that the Trump administration could slow the pace of this lighting revolution. Last month, the Department of Energy said it would withdraw an Obama-era regulation that nearly doubled the number of light bulbs […]