Frank Shuman (January 23, 1862 -- April 28, 1918) was an American inventor, engineer and solar energy pioneer known for his work on solar engines, especially those that used solar energy to heat water that would produce steam. Shuman's visionary ideals, most of which were not publicly accepted until sixty years later, were evident when he made the statement, "One thing I feel sure of... is that the human race must finally utilize direct sun power or revert to barbarism."