Frank Shuman built the world’s first solar thermal power station in Maadi, Egypt (1912-1913). Shuman’s plant used parabolic troughs to power a 60-70 horsepower engine that pumped 6,000 gallons of water per minute from the Nile River to adjacent cotton fields. His system included a number of technological improvements, including absorption plates with dual panes separated by a one-inch air space. Although the outbreak of World War I and the discovery of cheap oil discouraged the advancement of solar energy, Shuman’s vision and basic design were resurrected in the 1970s with a new wave of interest in solar thermal energy