If oil, coal and gas are fossilised sunshine, why not take a more direct route?
Meet Augustin Mouchot, a man with an amazingly vertical moustache, and a vision for sunshine-power way ahead of his time.
Born in Semur-en-Auxois - a medieval town in Eastern France, roughly halfway between Paris and Lyon - in April 1825, Mouchot started working life as a maths teacher, but managed to get government funding to study solar power full time.
He started playing with Saussure’s solar ovens - which, you might remember, also helped Fourier come up with the idea we know call the greenhouse effect - as a way to develop steam power without the need for coal. Put a cauldron inside a glass box acting as a small greenhouse, sit it in the sun till the water boils, then power a small engine off the steam.
But, wanting more power than a solar oven could produce, Mouchot developed the first parabolic solar trough - a sort of massive funnel of mirrors that concentrates the sunlight. The tech’s still used today, in concentrated solar plants (though it looks a bit different).
His first model was presented to Napoleon, but sadly seems to have been a casualty of Franco-Prussian War, as machine was not found after the siege of paris in 1871 ended.
Because it’s not just fossil fuels which have histories wrapped up in colonialism, Mouchot received a grant from the French government to conduct a ‘scientific mission’ to Algeria to experiment with their, especially abundant, sunshine. He returned to Paris for the 1878 Exposition Universelle - a World's Fair to celebrate the recovery of France after the Franco-Prussian War - to show off his new solar developments, which is where the illustration above comes from. Apparently part of the idea used ice to concentrate the solar energy, which sounds super-clever and it won a prize, though I'm not sure what he did exactly. His assistant Abel Pifre also developed a solar powered printing press too. Apparently, even when it was cloudy, the press could work continuously all afternoon, producing 500 copies an hour of a special solar-themed publication produced for the event, the ‘Soleil-Journal’.
But coal was cheap. And solar power wasn't really all that efficient. Yet. So the French government cut Mouchot’s solar research funding, and he went back to teaching maths.
The movement of electrons we’d now generally think of as solar power - solar photovoltaics, those shimmery, blue squares your neighbour maybe has on their roof - took a bit longer to get going. But the basic principle that you can make electricity when sunshine falls on particular substances also dates back to the mid-19th century.
In 1839, a young scientist (just 19, working in his father's lab), Edmond Becquerel first observed what we’d now call the photovoltaic effect, noticing he could create a very small electric current when plates of some metals were immersed in an acid solution and exposed to sunlight.
Next up, English electrical engineer, Willoughby Smith, discovered the a photovoltaic effect of light on selenium and published his results in the journal Nature in 1873. Then in 1883, American inventor Charles Fritts built what could be described as the world’s first solar cell (though there are a few stages along the way that also claim that title) using selenium and a very thin layer of gold. It was only 1% efficient, so wasn’t exactly going to compete with coal yet. But it was a start, and there followed a flurry of patents and proto solar entrepreneurs around the turn of the century, even if the tech had to wait till the Cold War to really get going.
The next key step in solar energy was an accidental discovery at Bell Labs in 1940. Russell Shoemaker Ohl was playing with some silicon samples, and noticed one with a crack in it. Impurities had built up on either side of the crack, one side positively charged, the other negative. When he shone light on this odd little broken and dirty sample, a current would flow. Ohl had inadvertently made a positive-negative junction, the basis of the modern solar cell. A load of positive charge builds up on one side, and a load of negative charge builds up on the other, creating an electric field. Photons can then kickstart the flow of electrons (aka electricity). This was the first silicon based solar cell, and though it was still no more efficient than Fritt’s 1880s selenium idea, was the basis of a lot of our modern solar industry. Diodes - like LED lights - are also descendants of this research.
Over a decade later, in 1953, another Bell Labs researcher, engineer Daryl Chaplin was looking into power for remote humid locations, and dug up the idea of solar power. He teamed up with chemist Calvin Fuller and physicist Ferald Person, who convinced him to switch from selenium to silicon, and then tinkering with adding different impurities to make them more efficient, eventually settling on mix of arsenic and boron.
Bell Labs proudly presented their new 6% efficient cells to the world in April, 1954, using a strip of them to run first toy ferris wheel, and then a radio transmitter that could broadcast music to top scientists gathered at a meeting DC (solar PR started a long time before Elon Musk…). Happily getting on board with the solar hype, the New York Times wrote the new invention ‘may mark the beginning of a new era… the harnessing of the almost limitless energy of the sun for the uses of civilization.’
The serious application wasn’t toys or radios though. It was space. In March 1958, Vanguard 1 used Hoffman Electronics new 9% efficient solar cells to power the first solar satellite. By the 1960s, solar had become the main power source for most Earth orbiting satellites - it's partly because there isn't much else to choose from up there, so it’s worth the cost, and the money the space programme poured into solar research helped bring down prices for terrestrial applications.
Vanguard 1 is still up there - the oldest manmade satellite in orbit, even though we lost communications with it in 1964 - if you want to give it a wave some time.
Like wind, the oil dramas of the 70s led to a bit more investment in solar energy, including some investment from oil companies. In 1973, the University of Delaware also unveiled Solar One - a super energy efficient solar house - to showcase domestic solar living. It was visited by over 100,000 people in its first year, before being repurposed into a student home, and then university offices.
In 1979, President Jimmy Carter installed solar panels on the White House, which were later infamously removed by Regan, and reintroduced by Obama. As Nature points out, in the meantime, some solar panels quietly installed in the White House garden under George W. Bush, seemingly without his knowledge, or interest “which seems to sum up his attitude to greenhouse-gas emissions rather well”.
Carter also introduced feed-in-tariffs in 1978 - a way of encouraging investment in renewables. One of the impacts of feed-in-tariff policies, around the world, has been to encourage everyday homeowners and community groups to get involved in energy production by tapping into the relatively easy deployment of technologies like solar and wind, and that they can be built in a range of different sizes.
In the last few decades solar’s steadily got a lot bigger. It’s also got incredibly cheap. It remains ridiculously popular with the general public, and the press retain an enthusiasm for stories of gee whiz solar awesomeness (from solar made from tofu to spray-on solar).
The popularity might be something in the association with sunshine as pleasant weather - at least compared to wind - or maybe the tech has never worn off the space age sense of shiny futuristic utopia (even if that utopia is a good 60 years old, even 120 years old in places). It could also be that so many of us have the chance to interact with solar, putting it on our schools, houses or community buildings ourselves, not just looking at it from afar, in a field and expecting other people to deal with energy supply for us. Solar isn’t democratic or decentralised by its nature - it could all just be done in large scale, closed systems - but it has the possibility to be so.
When it comes to solar’s future, it’s safe to bet we’ll see a lot more of it, and it’ll be a lot cheaper. Possibly it’ll be made from tofu and/ or beamed down to us from space, but it probably doesn’t need to be it. Coupled with storage, it’ll applied on domestic level more and more, as well as on a large scale. Similar to possible futures for wind energy, who’ll own it is another matter though.
But this whole post has mainly an excuse to share one of the corniest songs in the history of climate change - Pete Seeger’s Solartopia. So press play, and allow yourself a few moments of cheesy hope.