The Power of Lightning In A Flux Capacitor

In 1985 the term “flux capacitor” became a household name when the film Back to the Future catapulted to the top of the charts, and the movie has remained one of the most beloved in cinematic history.

As we all know, in the film, Doc Brown invents the flux capacitor – a device that will power his time machine – after suffering a head injury (which is, of course, a surefire way to have an Earth Shattering scientific breakthrough). Doc initially powers the flux capacitor with plutonium. When scary high jinx and sad shenanigans ensue (no spoilers here!), Marty is accidentally sent back in time – sans plutonium for his return trip.

To return to the correct time, Marty needs to power the flux capacitor with 1.21 gigawatts of power – which Young Doc Brown (who Marty is hanging out with in 1955) famously declares would take “a lightning bolt to generate that kind of energy!”

How Much Power IS 1.21 Gigawatts?

As it turns out, 1.21 gigawatts is a lot of power. A gigawatt is equal to one billion watts, and the lightbulbs in residential buildings are typically 60 to 100 watts. That means that 1.21 gigawatts could power 10 million lightbulbs … or one flux capacitor.

Since it’s unlikely that Marty and Young Doc could have ever found 10 million lightbulbs (nevermind in 1955) and plutonium was harder to come by in 1955 than it was in 1985 (naturally), they did the next best thing and waited for a lightning strike. Luckily for them (thanks to a few clever screenwriters and a bit of foreshadowing), they knew exactly when and where a lightning strike was going to hit due to the broken clock tower in the town center.

A Laser Would Have Made It Easier…

Theoretically, Marty and Doc wouldn’t have needed to wait for a lightning strike if they had the power of lasers behind them. While the flux capacitor and suped-up Delorean required 1.21 gigawatts of power to travel back in time, a laser can produce far more than that at a moment’s notice. In fact, there are now laser beams capable of producing one petawatt of power – or one quadrillion watts.

Unfortunately for them, however, the laser wasn’t invented until 1960 – five years after Marty’s trip. And that laser wouldn’t have been nearly powerful enough – coming in at only 1 milliwatt. At the time, the laser was called “a solution looking for a problem,” since there weren’t any known applications for it.

Within a few short years, however, lasers had become an integral part of the scientific and industrial landscape, and they’re now a fairly common part of everyday life, whether we realize it or not.

At Blue Ridge Optics, we’re ready, willing, and able to help the next generation of Doc Browns travel back and forth on the space-time continuum with laser-powered flux capacitors, as our standard Hi Energy line of AR coatings have been tested to with stand more than 10 gigawatts of power, and HRs of more than 8 gigawatts (1064 and 1540nm at 10nsp).