HJ-ED-DHJHerald Journal Columns
July 2, 2007, Herald Journal

Wireless electricity arriving soon


In the very near future, we will no longer need to plug in our cell phones, laptops or other rechargeable electronic devices into an AC outlet by using a power cord.

A very bold statement indeed – but this is what we will see happening very soon.

Not long ago, six Massachusetts Institute of Technology (MIT) researchers stood between two large copper coils, about one and half feet in diameter each. One of these coils was connected to a power source, the other coil connected to a 60 watt light bulb.

When the power switch was turned on, the bulb glowed.

The bulb was six feet from the coil connected to the power source.

“What is so remarkable about this?” you may be thinking.

There was only “air” in those six feet that the electricity traveled through to light the bulb. No wires, no cords, no smoke and no mirrors.

Are you stunned, amazed and wondering what this week’s column is going to cover?

Hang on faithful readers, as we take a look at “wireless electricity.”

Today we have wireless phones and our notebook computers can access the Internet wirelessly. We have wireless home networking, wireless mice, keyboards and even those indispensable wireless garage door openers too.

And now. . . get ready for the next hot wireless technology we will soon find ourselves using.

Portable wireless charging pads.

Imagine wirelessly recharging your computer laptop, cell phone, iPod, iPhone, PDA, toys, toothbrushes or electric shaver simply by placing them on the “charging pad surface.”

The idea of using “wireless energy” to provide our power needs is not something new.

In fact, it was being experimented with over 100 years ago.

Nikola Tesla was a famed inventor, physicist and electrical engineer.

Tesla created a “coreless transformer” for high-frequency currents, which is known as the “Tesla Transformer.”

Nikola Tesla’s notes on the experiments stated that “. . .stationary waves spread through the Earth. . .so this effect could be used for [the] “wireless transmission of energy.” Tesla was granted patents in the area of “wireless transmission of energy” from 1900 to 1902.

From 1901 to 1905, Tesla was determined to realize his “World-Wireless-System.” He was occupied with the construction of a great experimental station, a power plant and an aerial tower on Long Island near New York city. However, this project was never fully completed.

Back to 2007.

I found six companies that are working to provide wireless electrical charging devices, including Apple Computer. Apple applied for a patent application for a wireless docking station that would allow wireless charging for several Apple handheld devices.

I visited one of the companies called “WildCharge” online and viewed a photograph that shows a heavy plastic pad less than a foot square, (which plugged into an AC outlet). Several “wirelessly-chargeable” compatible devices (cell phones, digital recorders) were placed upon it.

This “base” is actually the charging pad for the devices being re-charged. The “charging-power” was fed wirelessly from this electronically modified plastic base into the devices lying on the pad.

You can see this amazing photo on the bottom of their webpage at: http://www.wildcharge.com/.

I looked for an explanation that would satisfy my lack of understanding on how you can charge a device’s battery without it being in direct metallic contact with the charging source. This goes against everything I learned in the Wadena Vo-Tech electronics lab.

I found there are three basic technologies for wireless electricity (power) charging: radio charging, resonance charging, and induction charging.

Radio charging is compatible for charging low-power devices at long distances of around 30 feet away. This technology is perfect for “trickle-charging” those small RFID’s (Radio Frequency Identification devices) or “tags” that are attached to products in a company’s warehouse.

Resonance charging makes sense for devices that require a lot power over a close distance like vacuum cleaners, kitchen appliances, shop power tools and other similar devices. They essentially make contact with the plastic, but not the metal.

Soon we will see toothbrushes, electric shavers and other similar “portable-devices” use induction charging. This technology uses a coil to create an electromagnetic field across a charging station surface (like the heavy plastic charging surface pad mentioned earlier). The particular device then converts power from the field back into usable electricity, which then charges the battery inside the device.

Oh sure, I know there are more scientific and detailed explanations. . .sprinkled with an assortment of electrical jargon, schematics and algorithms – but I just write around 800 words every week.

Meanwhile, those researchers at MIT have also come up with a way to wirelessly supply power that could lead to the development of devices – that don’t require batteries at all.

What will the “Energizer Bunny” do for fun then?

These new wireless charger adapters may not appear until the second half of this year. . . or later.

Until then, we’ll just have to keep recharging our stuff the old fashioned way.

You can visit the Nikola Tesla online museum at http://www.tesla-museum.org/.