In sunny California, solar panels are everywhere. They sit in dry, desert landscapes in the Central Valley and are scattered over rooftops in Los Angeles’s urban center. By last count, the state had nearly 47 gigawatts of solar power installed - enough to power 13.9 million homes and provide over a quarter of the Golden State’s electricity. But now, the state and its grid operator are grappling with a strange reality: There is so much solar on the grid that, on sunny spring days when there’s not as much demand, electricity prices go negative. Gigawatts of solar are “curtailed” - essentially, thrown away. In response, California has cut back incentives for rooftop solar and slowed the pace of installing panels. But the diminishing economic returns may slow the development of solar in a state that has tried to move to renewable energy. And as other states build more and more solar plants of their own, they may soon face the same problems. “These are not insurmountable challenges,” said Michelle Davis, head of global solar at the energy research and consulting firm Wood Mackenzie Power and Renewables. “But they are challenges that a lot of grid operators have never had to deal with.” Solar power has many wonderful properties - once built, it costs almost nothing to run; it produces no air pollution and generates energy without burning fossil fuels. But it also has one major, obvious drawback: The sun doesn’t shine all the time. |