400 B.C.
Greeks were the first to build their houses in a way that would benefit from the sun's heat during winter.

1767
Horace-Benedict de Saussure a scientist from Switzerland created the first solar collector in 1767. It was a sort of insulated box that used three layers of glass to absorb heat energy. This box was able to reach temperatures of 230 degrees Fahrenheit or 110 degrees Celsius and became known as the first solar oven. This solar oven was later used by Sir John Herschel to cook food during his South Africa expedition in the 1830s.

1839
This is the year Edmond Becquerel, a French scientist, experiments with two electrodes placed in an electricity conducting solution and discovers the electricity increases when it is exposed to light. This is now called the photo-voltaic effect.