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An Early Focus on SolarThe sun-drenched swaths of land in southwestern Spain seem custom-made for large solar projects. Add generous government subsidies to this hospitable climate, and the solar opportunity in regions like Andalusia and Extremadura would seem almost too good to be true.In fact, it was too good to last.In the wake of an overheated solar market and the global financial crisis, Spain has slashed its renewable energy subsidies. And the solar boom under the Mediterranean sun has gone bust—a stunning reversal of fortune: In 2008, 40 percent of the world's solar installations were in Spain.But it's hardly the end of the road for the technologies nurtured on the Iberian peninsula. Spanish companies are working to export their know-how to the United States, Latin America and even to other European Union nations.Although the United States developed experimental solar power towers in the Mojave Desert in the wake of the 1970s energy crisis, it was nearly three decades later that Spain put the world's first commercial solar tower online in March 2007, 15 miles west of Seville in southern Spain's Sanlúcar la Mayor. The Planta Solar 10 solar tower plant, seen above with sunlight glinting at the top of its 377-foot (115-meter) tower, can provide electricity for as many as 5,500 homes and store energy for up to 30 minutes.Like all concentrating solar plants, power towers use steam turbines to drive a generator to produce electricity. But developers long believed using circular rows of mirrors to focus the sun's rays on a central "power tower" would be more efficient than other types of reflector arrays, and would make it easier to integrate technology to store energy.From a distance, the result is an otherworldly scene akin to a high-tech crop circle or an alien amphitheater. Up close, the projects resemble fields of giant mechanical sunflowers craning their shiny faces toward a glowing tower.(Related Pictures: "Cars Capture Solar Energy in the Chilean Desert")—Josie Garthwaite

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Photograph by Markel Redondo for Greenpeace

Pictures: Spanish Solar Energy

Spain’s solar energy boom of the past decade has waned, but the Iberian peninsula nurtured innovative technologies that may pave the way for future large-scale renewable energy.

February 29, 2012