We predicted that in “a few years hence,” science would find
a way to harvest the full power of the sun. We’re still waiting.
“Sunshine, our greatest source of potential power, is now largely wasted,” we declared in October 1934. But that’s not for lack of trying: Throughout history, humans have harnessed the sun’s power with increasingly sophisticated contraptions. One of the first uses of solar energy came in 214 B.C., when Archimedes set Roman warships aflame with reflected sunlight. Things got more complex in 1874, when engineer August Mouchot delivered 0.5 horsepower from a solar-powered steam engine (the steam was generated by transferring heat from a