High-tech batteries may be garnering the headlines. But utilities from Spain to China are increasingly relying on pumped storage hydroelectricity – first used in the 1890s – to overcome the intermittent nature of wind and solar power. In the past decade, wind energy production has soared in Spain, rising from 6 percent of the country’s electricity generation in 2004 to about 20 percent today . While that is certainly good news for boosters of clean energy, the surge in renewables has come with the challenge of ensuring that electric power is available when customers want it, not just when the wind blows. Photo credit: Iberdrola. Spain’s Cortes-La Muela project, which uses pumped hydro storage to produce electricity. To help accommodate the increased supply of wind, Spain’s utilities have turned not to high-tech, 21st-century batteries, but rather to a time-tested 19th-century technology — pumped storage hydroelectricity. Pumped storage facilities are […]