Use the solar timeline to learn some interesting facts about solar technology.
4.54 Billion Years Ago
The Earth forms and begins to absorb energy from the Sun.
7th Century BC
People use simple magnifying glasses to concentrate sunlight and make fire.
5th Century BC
Greeks use passive solar housing design.
1st Century AD
Romans use a form of glass in window openings to retain the Sun's heat.
6th Century AD
Roman laws prohibit tall buildings that block sunlight.
13th Century AD
Anasazi people build south-facing cliff homes. Italians build modern greenhouses.
Swiss scientist Horace de Saussure builds the world's first solar collector.
A period of solar thermal and photovoltaic advancement begins.
American inventor Charles Fritts develops a working solar cell.
Albert Einstein publishes a paper on the photoelectric effect with his theory of relativity and later receives the Nobel Prize for his efforts.
California and Florida homes use flat-plate thermal collectors for water heating.
U.S. researchers at Bell Labs develop six percent efficient silicon solar cells.
The U.S. launches the first spacecraft with solar panels—satellite Vanguard 1.
Solar cells power U.S. Space Station Skylab.
Operation of the Solar Energy Research Institute, now the National Renewable Energy Laboratory (NREL) begins in Boulder, Colorado.
The United States Department of Energy forms.
President Carter installs solar panels on the White House.
American physicist and inventor Paul MacCready builds Solar Challenger—the first piloted solar-powered aircraft.
The first biannual solar car race—World Solar Challenge—takes place in Australia.
The NREL's Solar Energy Research Facility is established.
President George W. Bush installs two solar water-heating systems at the White House.
Solar cell efficiency exceeds 40 percent.