A look at the modern marvel of wireless charging

Will plugs someday soon go the way of the dinosaur? Probably not, but wireless charging increasingly makes plugging into outlets unnecessary. Many phones, Bluetooth speakers, tablets, and other gadgets can now be charged wirelessly. Yet while wireless charging has become one of the latest tech crazes, it’s been around for over a century.

You may have heard of the Tesla coil. Invented by the brilliant Nikola Tesla, the coil allowed for the transfer of electricity without the need for wires. However, the coil could only transfer energy over short distances, and the powerful open charges could kill or seriously maim people.

These days, wireless charging isn’t so deadly. Currently, “Qi” is the most popular wireless charging standard, using inductive and resonant charging. With inductive wireless charging, a sending coil will send out a signal, which is then received by another coil, generating an electromagnetic field. This gets the electrons in the receiving coil to move, thus creating electricity.

For inductive charging to work, the sending coils must be aligned and touch one other. A newer method, called resonant charging, was invented at MIT in 2006. Resonant charging uses two coils operating on the same resonant frequencies, facilitating energy transfer over short distances, meaning devices don’t need to touch.

Inductive charging is more efficient than resonant charging. As a result, you can charge devices more quickly while using less electricity. Meanwhile, resonant charging offers convenience.

However, even inductive charging isn’t particularly efficient compared to the traditional plug.

Still, no matter how you cut it, wireless charging is far more efficient and practical today than the infamous Tesla coil. And with scientists continuing to tinker with charging solutions, the future is bright and wireless indeed.