Experimental silicon solar cell

Scientists and inventors in the 19th century recognized that some materials respond electrically to exposure to light. Alexander Graham Bell, for example, demonstrated in 1880 a “photophone” that could transmit voices using the action of sunlight on selenium. In the 1930s, Daryl Chapin studied magnetic recording at Bell Labs but later shifted to research on generating electricity with sunlight. In 1954, building on earlier work done by colleague Russell Ohl on fused silicon, Chapin, Calvin Fuller and Gerald Pearson invented a practical solar cell. In 1969 Chapin donated two of his experimental solar cells to the Smithsonian. He also donated a module used in a test installation in Americus, Georgia, to power a rural telephone relay.