A Brief History of Solar Energy

Pictures, sketches, and videos of many of the following events, applications, and devices as well as extensive additional historical information can be found on the Sun's Joules CDROM. The history of solar cells, or photovoltaics, will be covered in the High Tech section.

Greeks

• 1st written account of solar energy use: 4th century BC when a scarcity of wood forced fuelwood imports from Middle East
• Socrates laid out principles of passive solar design:
  • 1. main rooms should face south
  • 2. north side of buildings should be shielded from the cold winds
  • 3. eaves should be added to provide shade for south windows in summer

• 212 BC Archimedes allegedly used solar energy to "reduce the Roman navy (which was attacking Syracuse) to ashes" by having soldiers reflect sunlight off their shields toward Roman sails

Romans

• Central heating and large central baths quickly consumed forests around Rome
• Romans expanded use of solar energy:
• 1st century AD introduced glass (recognized greenhouse effect)
• used dark colors and pottery to store thermal energy
• 1st to legislate domestic solar rights (2nd century AD)
• 37 AD: 1st greenhouse used to grow cucumbers for Tiberius Caesar

Other early civilizations (Chinese, Anasazi, Pueblo) used solar energy for heating, water evaporation, and other applications

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1500's : da Vinci

1515: Leonardo da Vinci conceived of a parabolic mirror concentrator for an industrial application (cloth dyeing)

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1700's

1700: Antoine LaVoisier built a solar furnace that could melt platinum (3236°F, 1780°C)

1767: Horace de Saussure invents 1st flat plat collector (Switzerland)

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1800's

early 1880's: US engineer John Ericsson (designer of Monitor ironclad ship) designed and demonstrated a solar heat engine

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1900's

• circa 1900: solar water heater industry emerged in S. California
• circa 1920: natural gas discovered in S. California, ending solar industry there
• 1923: solar water heater industry moved to Florida
• 1939: MIT built 1st active solar house
• 1941: government froze civilian use of copper due to WWII, halting production of solar water heaters
• circa 1950: US lifestyle changes made solar water heaters too small
• 1950's: cheap electricity and fossil fuels made solar products too expensive
• 1973: OPEC Energy Crisis causes US to reexamine use of renewable energy sources; federal and state tax credits result in rapid growth for a new solar industry
• 1986: tax credits for residential solar systems ended causing 30,000 US workers to lose jobs
• 1996: Solar energy used to heat water for swimming events at Atlanta Olympic Games