The sun is the source of energy for just about everything on Earth. So if you really want to be pedantic about it, the history of solar power goes back all the way to the start of Earth itself. However, following that line would be pretty silly. So instead, I’m only going to stick to how humans have used solar energy across history.

Praise the Sun

When we say “solar power”, that’s not just confined to electricity. Humans have put the heat of the sun to many uses. One of the simplest examples is using the sun to dry clay bricks, a fundamental step in creating civilizations. People knew how to make glass magnifiers as a way to start a fire as far back as 700 BCE. Legends say that the Greeks had reflective bronze shields which could set ships on fire at a distance. Although this is probably not exactly true, some experiments using the descriptions of the process have actually worked. Egyptians used mirrors for internal illumination in the deep parts of buildings. By the late 1700s, solar ovens were invented, allowing cooking without burning any fuel.

We certainly found plenty of uses for the sun beyond just getting a tan and growing healthy veggies. That’s all fascinating, but I guess what anyone really cares about is when and where we learned how to turn sunlight into electricity.

The First Sparks

It seems that most historians agree that the history of photovoltaic cells starts way back in 1876; well into the industrial revolution and the use of electricity for industrial purposes. It was in this year that William Grylls Adams and his student Richard Day made the key discovery that enabled solar power technology to happen. They observed a photovoltaic effect in selenium. While the selenium was pretty awful at converting light to electricity, this discovery is important because it showed that sunlight could become electricity, something no one was even thinking. This knowledge would spark research and development, yet the selenium photovoltaic cell was of no practical use.

Making Itself Useful

It wouldn’t be for another 77 years, in 1953, that practical solar electricity would become possible. A team of three made the discovery. Calvin Fuller, Gerald Pearson, and Daryl Chapin first realized that another material, silicon, could produce electricity in usable quantities. It only took a scant three years before silicon solar cells were available to buy. The price-per-watt figure was, however, ridiculous. Not adjusting for inflation, a 1-watt cell would cost $300 – a lot of money for something that could barely power a child’s toy.

solar water heater

To Infinity and Beyond

While $300 per watt was way beyond what most people would pay for solar power, there was one customer who didn’t mind paying crazy amounts of money for new technologies. You guessed it – the space agencies.

Solar panel technology proved a godsend for space vehicles with long-term missions. It didn’t take any time at all for satellite technology to embrace solar power. In the late 50s and early 60s, both the USSR and the USA had satellites up that used the technology. Solar cells worked even better in space, without all that atmosphere in the way.

Price Per What?

So great. There’s a whole bunch of spaceman money going into the solar panel research pot, but if the technology is to have global appeal the price per watt has to come down fast. In the 70s things really came together. The cost of making a single watt of power from a solar panel was about twenty bucks. Now remote equipment and other stuff far from the grid began to make use of solar panels. It wasn’t just for keeping satellites going anymore.

Slow Uptakes

Despite all the work put into making solar power cheaper, it was really only used in situations where nothing else would cut it. In the mid 70s, only six North American homes relied on solar power for heating or cooling. That’s just heating and cooling, not general electricity.

The bevy of oil and energy market issues from then until the late 70s did provide some incentive to improve things. However, oil got cheap again in the 80s, which meant there was less incentive to go solar.

No Money, More Problems

The oil price reprieve of the 80s was short-lived and by the late 90s solar started looking mighty attractive again. This is the era when people started becoming aware of global warming, oil became more and more expensive, and computer technology was becoming a daily way of life. In other words, the groundwork was being laid in the mind of the public to accept green, clean, solar power.

Even better, in the early 2000s the idea of selling power back into the grid caught on. So now people had even more incentive to pony up for solar installation.

The Roller Coaster Starts Now

In the greater scheme of things, solar electrical power has not been around for all that long. Still, it’s taken 150-ish years to go from selenium cells that have an efficiency close to zero to commercial PV panels that can hit more than 20% efficiency. In labs, experimental panels have exceeded 40 percent!

With the rise of electric and smart vehicles, the dominance of digital equipment, and the unsustainability of fossil fuels, solar may become one of the most dominant sources of energy in our civilization. Most of the history of solar energy has yet to be written and we get to live through its golden age.