Dec 11, 20226 min read

Was Edison Right All Along?

In the late 19th century, America was gripped by an engineering battle that would forever change the world. In the ‘war of the currents’, inventors Thomas Edison and George Westinghouse (with some help from Nikola Tesla) raced to find the best way to bring electricity to cities and industries.

Edison favoured a system called direct current (DC) while Westinghouse championed alternating current (AC). After a brutal fight, the latter won out, the world adopted AC, and the rest is history. Or is it?

In this explainer video I look at the case for DC, and ask whether Thomas Edison might have the final say after all:

The war of the currents: A brief history

Today, alternating current (AC) grids bring electricity to more than seven billion people. To understand how this came to be, let’s take a step back in time to 1880s America and the war of the currents.

Picture the scene — you’ve had a great idea at work but your boss just isn’t interested. What do you do? Take it on the chin and move on? Bide your time and try again later? Or quit your job on the spot and prove your boss wrong by joining forces with their biggest rival to revolutionise science and change the world? Ok, that last option isn’t quite as relatable as the others. But this was the dilemma facing the relatively unknown yet brilliant scientist Nikola Tesla.

Tesla idolised the American inventor and businessman Thomas Edison — so much so that he moved continents to work for him. Born and raised in the Austrian Empire, Tesla spent a while working for Edison’s European business in Paris before emigrating to the US to work directly with the man himself. It was an exciting time to move – Edison had recently built a DC generator which was now powering New York. (Edison’s Pearl Street power plant would keep going for another 125 years).

In 1884, Tesla got a job working at the Edison Machine Works factory on the industrial lower east side of Manhattan. He told his new boss that he could improve some of his designs. In response, a perhaps sceptical Edison told this young upstart to go knock himself out and offered a $1 million bonus (in today’s money) if he could actually achieve it. The thing was, Tesla was something of a genius himself. He really did improve the efficiency of Edison’s designs. And about that bonus? It turns out Edison was just kidding. “Tesla, you don’t understand our American humour,” he is said to have laughed. Not seeing the funny side, Tesla promptly quit, and so began an epic rivalry that would change the world.

The story is entertainingly retold in the 2019 film The Current War, which sees Benedict Cumberbatch as Edison performing the ‘difficult genius’ act he does so well. In the film’s retelling, Tesla wasn’t just annoyed about the money. He was growing increasingly frustrated by Edison’s stubborn refusal to consider the merits of AC as a more efficient method for transmitting electricity.

Tesla eventually threw his lot in with George Westinghouse, a successful entrepreneur who was also in a feud with Edison. As a young man, Westinghouse invented the railway air brake, and by the 1880s he had thrown all his resources into the exciting new business of electricity. Unlike Edison, he believed in the merits of AC which – though less safe – could carry electricity over much greater distances than DC.

The winning combination of Tesla’s engineering genius and Westinghouse’s business acumen were enough to persuade city after city to adopt AC as the best means to bring electricity to the masses. The more expensive DC system Edison pioneered in New York failed to catch on.

It didn’t end well for Edison and his campaign. He ended up a marginalised figure in his own company which, through a merger, had now become Edison General Electric. The final blow was dealt in 1892. Company bosses finally gave up the DC fight and adopted AC. To add insult to injury, they also dropped Edison from the company name. It was now to be known as General Electric.

The elephant in the room – did Edison kill Topsy?

The war of the currents was bitterly fought. Edison – furious that Tesla and Westinghouse were stealing a march on his invention – resorted to playing dirty. Convinced that AC was dangerous, he decided to prove it himself.

Legend has it that Edison organised a spectacular PR stunt to definitively show the dangers of AC. On New York’s Coney Island amusement park, he is said to have electrocuted a live African elephant, named Topsy, in front of a crowd of 1,500 people.

So, did this actually happen? Animal lovers might want to skip ahead to the next section…

Sadly, Topsy the elephant did meet her end through electrocution on Coney Island. But it happened in 1903 – a good decade after the war of the currents had ended. It was organised by the owners of the site on Coney Island, who declared that Topsy was too badly behaved to be kept under control. She had already killed three people by this stage, including a handler who tried to feed her lit cigarettes.

Edison isn’t completely in the clear though. He did instigate the electrocution of horses in his efforts to smear AC. By 1903, he had long since moved on to his latest passion project – film (Edison patented the first film projector in 1897). Edison may not have been present at Coney Island, but a camera crew from the Edison Film Company were. A week later they released a short film – believed to be the first to show death on screen – documenting the macabre spectacle.

The case for DC in 2022

Clearly AC was the outright winner in the war of the currents. But unlike the Betamax or the Minidisc, this losing format never went away.

The device you’re reading this newsletter on is powered by DC. And with the evolution of technology, we long ago solved the issue of moving DC over large distances. In fact, plans are underway for a subsea cable to carry wind and solar power over 2,000 miles from Morocco to the UK using high-voltage direct current (HVDC) – something which would not be possible with AC. The even more ambitious Sun Cable project will soon be exporting the power of the sun 4,000 miles from Australia to Singapore.

More than a century after losing the war of the currents, might DC finally have its moment?

Campaign groups like the EMerge Alliance exist today to promote direct current, citing many of the same benefits Edison was preaching back in the 19th century.

As we explored in a previous video on nuclear fusion, there is a pressing need to explore sustainable sources of energy as we wean ourselves off fossil fuels. And don’t forget – there are still almost a billion people on the planet who do not yet have access to electricity.

Whereas AC tends to use carbon-heavy methods of generation, DC works with generators like solar panels which – being powered by the sun – are DC by default. This means that DC generators can be set up in cities, towns and villages without polluting the environment with harmful fumes.

It’s a slightly different argument to the one Edison was making 140 years ago, but in one important sense he has been proved right. If DC can help to decarbonise our energy supply, then it really will be the safer and better option, for us and for the planet.