10 Things to Know About Wireless Power

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The hype cycle around wireless power has been gathering a charge ever since Intel (s intc) wowed folks at its IDF conference last year with a demo of wireless charging. Then over the summer, a TED video surfaced with a similar demo, starring the CEO of WiTricity. And this week we saw Dell (s dell) launch a notebook with wireless charging and Nokia (s NOK) join a new industry consortium dedicated to wireless power. But like other aspects of the wireless world, there are a lot of differences, issues and things that average outlet-avoiding consumer needs to know. Here they are:

1. Wireless power is an old idea (Tesla demoed it in 1891), but there are currently two camps trying to use magnetic induction to charge things, one offering a charging pad, and the other trying for over-the-air power.

2. The Wireless Power Consortium, an industry group formed to create standards around wireless power, argues that a charging pad is the only way to charge things efficiently. Members of the Wireless Power Consortium so far include Texas Instruments, Nokia, (which joined this week), Phillips, Samsung and Duracell.

3. The first WPC standard specification, called Qi, was released in August.

4. The goal is to use two magnetic coils, with one inside a charging pad and one (which can be added to devices for less than $1) inside a gadget that allow it to charge while sitting on the pad.

5. Efficiency rates range from 50 to 70 percent using this method, and can transfer 5 watts of power, according to Menno Treffers, chairman of the Wireless Power Consortium, and Dell, which says its laptop is 70 percent efficient.

6. A popular use of wireless power may be sitting in your bathroom. Phillips Sonicare toothbrush uses magnetic induction to charge the toothbrush. Yes, you still have to plug in the base charger.

7. Treffers expects wireless power to be in consumer devices like phones by 2011.

8. However, there’s another effort to make wireless power even sexier. Intel and WiTricity are trying to use magnetic induction to charge devices over the air. It’s pretty sweet, but so far efficiency is governed by how large the magnetic coils are and by how far apart they are from the device that needs power. The demos are using really big magnets or ones close together, and aren’t offering a lot of charging efficiency.

9. Plus, some people are worried about the effects of all that electromagnetic radiation flowing through the air.

10. So in the short term, charging pads and compatible devices are the closest we’re going to get to wireless power, unless we want to attach solar panels to our phones. But then we’re looking at a pretty long time to charge a device.