The sun back in the day

Nasso, Christine (2007). Solar Power. USA: The Thomson Corporation.

Greeks were first to use the sun to heat their houses. Even at 400 b.c. they knew it would conserve heat if they build their houses with most exposure to the sun. In 212 b.c., Archimedes (who was a great mathematician, engeneer, mostly inventor) used energy from the sun to reflect rays off the mirror onto the ship that was attacking his land. The roman sails had burned in the result. We don't know how true that story is, but there's a painting of the mirror's reflection showing us the history of the use of solar energy. Romans and Greeks built glasshouse to grow cucumbers for the Roman Emperor. They found a great use out of glass houses; it made it easier for fruits and begetables to grow. Back then people also relied on the sun to evaporate brackish water so that they could collect the salt. Also, as practical as they were, they took advantage of the colors; something painted dark attracted the heat from the sun, and bright colors reflected the light.