Goofy, or Genius?

Nikola Tesla’s Coil

When you see a “mad scientist” in a monster movie or on TV, chances are the character is based at least a little on Nikola Tesla. Tesla was an inventor and engineer who worked around the turn of the last century, and he was a brilliant — if kooky — man. Although Tesla is known for his pioneering work in many fields, his best-known invention is the one that bears his name: the Tesla coil.

Originally, Tesla developed his coil while working on a “wireless” lighting system; the idea was to build a device that could deliver power to gas light bulbs (like the fluorescent lights in your office) without any wires at all. Although other researchers were working on the same technology at the same time, Tesla was the first to see practical applications and patent his design. He was also the first to take his show on the road — literally. Just like those mad scientists on the big screen, Nikola Tesla loved showing off his inventions to the public.

The Tesla coil did work, but it had some serious drawbacks. The biggest one was efficiency; Tesla coils use a lot more electricity to do the same work electrical wiring does. Tesla claimed that, in theory, a coil could become self-sustaining, but neither he nor anyone else was able to build one that was. Even if coils were more efficient, though, there was still the problem of range — Tesla was never able to wirelessly transmit electricity more than a few feet, which is sort of a problem if you’re trying to light a house.

Although Tesla’s coil technology is still used in a few modern applications, they’re primarily educational tools these days. Tesla coils demonstrate neat electrical principles and can be built to shoot lightning bolts and generate electron winds — which is pretty nifty. They’re also a very scalable science experiment. You can build a miniature Tesla coil in your garage with materials from the hardware store, and amateurs have even built much larger coils that produce millions of volts.

We don’t recommend it, though. Like many mad scientific inventions, a full-size Tesla coil is very dangerous in the wrong hands. Instead, if you want to see Nikola Tesla’s coil in action, head to YouTube. You can also call around to see if there’s a coil at a museum near you.