Do you ever wonder how humans started using the power of the sun to get things done? The sun has been around a lot longer than we have, so you can imagine the history of sun power is pretty extensive. So in part 1 of this Sunpro Solar educational series, we’re going to take you from the beginning to the launching of solar technologies into space.
Are you ready to get your learning cap on? Let’s get to it!
The First Spark of Light
The first historical account of people using solar energy to get things done didn’t seem like much, but it sparked an entire solar energy revolution.
Way back in the 7th century BC people figured out how to use magnifying glasses to light fires. Remember when you were little and used to burn ants with glasses? Well, they did that too. And from then on they were using the sun’s energy to light torches, candles and even enemies’s ships!
Introducing the De Saussure “Oven”
The first exciting technological developments started to happen in 1767 when Swiss scientist Horace de Saussure built the first solar collector, which was later developed to use for cooking food.
This oven was a well-insulated box with three layers of glass to trap outgoing thermal radiation and the highest temperature he ever achieved was 230 °. By today’s standards it would take forever to bake anything, but it was a groundbreaking discovery that led to the development of solar cooker devices that are still in use today.
The Effect of the PV Effect
Since we love solar panels, we bet you’re wondering when the development of the solar panels started?
Let’s start with the basics. Solar panels are made of solar cells, or PV cells. Solar cells convert the energy of light directly into electricity by something called the photovoltaic (PV) effect.
The first real work achieved on solar cell technology was in 1839 when French scientist Edmond Becquerel discovered the PV effect. The PV effect showed the ability of a solar cell to convert sunlight into electricity.
This discovery opened a whole new world of possibilities for the future of the solar cell.
Selenium Gets Involved…
The next important point in solar cell technology was in 1873 when Willoughby Smith discovered that selenium had photoconductive potential, leading to William Grylls Adams’ and Richard Evans Day’s 1876 discovery that selenium creates electricity when exposed to sunlight.
…And Leads to an Early Version of the Solar Cell
Which led to Charles Fritts producing the first solar cells made from selenium wafers in 1883. (No, not like vanilla wafers cookies.) Fritts spread a wide, thin layer of selenium onto a metal plate and covered it with a thin, semi transparent gold-leaf film.
This selenium module produced power when exposed to not only sunlight, but also to dim diffused daylight, and even to lamplight!
In fact he was such a visionary, he is quoted as saying this about the future of solar energy “we may ere long see the photoelectric plate competing with [coal-fired electrical-generating plants].” At the time, coal plants were merely 3 years old.
If he only knew what was to come, he would be proud. In fact, 2020 is the first year since the coal miner’s strike in 1978 that coal production fell to its lowest level, and solar energy is still on the rise.
The Dark Ages of Solar Energy
Even though this was a huge discovery by Fritts, solar cell development dropped off again until the next century. This is because it was just not a usable product yet, and nobody’s interested in a product that isn’t market ready.
The head of Westinghouse’s photoelectricity division said at the time: “the photovoltaic cells will not prove interesting to the practical engineer until the efficiency has increased at least fifty times.”
They didn’t know at the time all they needed was silicon. And they wouldn’t find out until after the beginning of the silicon revolution.
The Birth of the First Silicon Solar Cell
Finally, in 1954 PV technology is born in the United States. The pioneers were Daryl Chapin, Calvin Fuller, and Gerald Pearson who developed the silicon PV cell at Bell Labs. This solar cell was capable of converting enough of the sun’s energy into power to run everyday electrical equipment.
Solar Goes Commercial
Solar products are everywhere you look now, but it all started in 1955. Western Electric was the first to start selling commercial licenses for silicon PV technologies.
And then the solar products started popping up. The early successful products included PV-powered dollar bill changers and devices that decoded computer punch cards.
And around the same time, architect Frank Bridgers designed the world’s first commercial office building using solar water heating. In fact, this solar system has operated ever since and is now in the National Historic Register as the world’s first solar heated office building.
It is called, as you would expect, the Bridgers-Paxton Building and you can find it in Albuquerque, New Mexico.
Solar Goes to Space Step One
Right after solar technologies went commercial, the idea of sending solar to space forms. In 1956, William Cherry of U.S. Signal Corps Laboratories got together with RCA Labs’ Paul Rappaport and Joseph Loferski and they had their first discussion about developing PV cells for orbiting Earth satellites.
Solar Technology is Launched into Space
And then, just two years later, the Vanguard I space satellite was built with a small solar array to power its radios.
Later that year, Explorer III, Vanguard II, and Sputnik-3 were launched with PV-powered systems on board.
Since then, solar is the accepted energy source used for space applications.
The Slow Search for More Efficient Solar Cells
The solar cell that we use in solar panels today are pretty efficient, although they weren’t always. Finding a solar cell deserving enough to be in a solar panel was a slow, long process. About each year the solar cell gained about 1% efficiency, led by Hoffman Electronics.
In 1957 they were 8% efficient. In 1958 9%, in 1960 10% and finally 14% by 1960. And they didn’t reach 20% efficiency until 1985!
Even now, top notch solar panel providers like LG are working hard every year to advance their technology.
What’s Next for Solar Energy Technology?
Curious what happens next in the advancement of solar energy technology? Stay tuned for part 2 when we take you through 2020- and beyond!