Photovoltaics are devices that use what is known as the photovoltaic effect to generate electricity from sunlight. Knowledge around this phenomenon has only been around for about two centuries, which is why the history of solar cells (photovoltaics) begins in the middle of the article.
700 BC – Sunlit Fires
We know that all the way back to the 7th century B.C., humans figured out how to make fires by concentrating the sunlight with magnifying glass.
214–212 B.C. – Archimedes’ Heat Ray
Historians claim that Archimedes, a Greek inventor, put solar energy to use already in the 3rd Century BC. He destroyed enemy ships with fire during the Siege of Syracuse with a “heat ray”, which supposedly was a collection of mirrors that concentrated sunlight onto the ships. Whether or not Archimedes’ invention has any root in reality is uncertain. Several experiments have been carried out to verify or bust the story, most of which concluded in the phenomena being possible, but highly unlikely.
1767 – The First Solar Oven
A solar oven, or solar cooker, uses sunlight to heat meals or drinks. Today’s solar ovens are cheap and popular solutions to prepare meals in parts of the world where access to electricity is limited. These devices are only reliant on sunlight to work – there is no fuel required.
Already in 1767, the first solar oven was invented. The credit goes to Horace de Saussure, a Swiss physicist, which probably had no idea his invention would help people prepare their dinner two and a half centuries into the future.
1839 – The Discovery of the Photovoltaic Effect
1839 marks a big year in the history because Edmund Becquerel, a French physicist, only 19 years old at the time, discovered that there is a creation of voltage when a material is exposed to light. Little did he know, that his discovery would lay the foundation of solar power.
1873 – Photoconductivity in Selenium
Willoughby Smith, an English engineer, discovered photoconductivity in solid selenium.
1876 – Electricity from Light
Building on Smith’s discovery three years before, professor William Grylls Adams, accompanied by his student, Richard Evans Day, were the first to observe an electrical current when a material was exposed to light. They used two electrodes onto a plate of selenium, and observed a tiny amount of electricity when the plate was exposed to light.
1883 – The First Design of a Photovoltaic Cell
An American inventor, Charles Fritts, was the first that came up with plans for how to make solar cells. His simple designs in the late 19th century were based on selenium wafers.
1905 – Albert Einstein and the Photoelectric Effect
Albert Einstein is famous for a wide variety of scientific milestones, but most people are not aware of his paper on the photoelectric effect. He formulated the photon theory of light, which describes how light can “liberate” electrons on a metal surface. In 1921, 16 years after he submitted this paper, he was awarded the Nobel Prize for the scientific breakthroughs he had discovered.
1918 – Single-Crystal Silicon
Jan Czochralski, a Polish scientist, figured out a method to grow single-crystal silicon. His discoveries laid the foundation for solar cells based on silicon.
1954 – The Birth of Photovoltaics
David Chapin, Calvin Fuller and Gerald Pearson of Bell Labs are credited with the world’s first photovoltaic cell (solar cell). In other words, these are the men that made the first device that converted sunlight into electrical power. They later pushed the conversion efficiency from 4% to 11%.
I hope you enjoyed reading about the history of solar energy and photovoltaics. If you miss any key events on this timeline, use the comment section below and we’ll make sure to add them as soon as possible.