The Tabernas desert in Spain gets 320 days of sun a year, which made it the perfect place for the Plataforma Solar de Almerķa (PSA). The German Aerospace Center (DLR) has been part of the solar energies research facility since its beggining in 1981. More than 20,000 square-meters of mirrors fill the 100 hectare facility -- that's as big as 225 football fields.