We are starting to get questions about this. It is a wireless charging device that was just approved by the FCC. Sounds like cool space age tech, doesn’t it? Well, it is really just a repackaging of an old principle. Tesla did experiments with this long ago, which despite his accomplishments, showed a lack of understanding of power distribution. The claims then were free wireless power to the world. I worked on building a version of this when I was 13, my son did a science project on it when he was in middle school. The range is nothing like what was imagined.

Basically the power from a radio transmitter can be collected, and rectified to charge a battery, or run a small device. What the FCC just approved with the operation of the transmitter, and it really doesn’t indicate an endorsement of the effectiveness, usability or efficiency of the device. The stated range is three feet, but if you have every tried to use one of the little blister pack radios to their full stated range, you can imagine how accurate that range estimate will be.

The additional thing that is not advertised in these designs is the power loss. The transmitter sends the power out in all directions, but only part of it is recovered by the receiving device. This is why Tesla’s original design failed.

There is some irony that in a world where people are worried about global warming, exposure to power line field, and cell phone exposure that there would be such a rush to embrace a device that transmits energy in to the room just to save three feet of cable. Wireless communications technologies are great tools for mobility, but there are times to just plug the device in.
Here is a description of different Wireless power technologies