The NYTimes is carrying a story today about a wireless charging startup called uBeam, which claims to be able to send power and data to portable devices using ultrasound.
uBeam’s promise is that portable (and by inclusion wearable) devices could have ever-smaller batteries because they would be able to suck power out of the air in rooms or facilities equipped with uBeam’s technology. We’re not physicists, but it would appear to us that power-to-ultrasound technology would be horribly inefficient in converting between sound waves and electricity. The Times piece is mute on how much power uBeam hopes to be able to move, and to how many devices at a time. Also, there must be a dreadful drop-off in transmission the further a device is from the uBeam source; if we remember high school, the decay is the square of the distance from the power source.
The company says its filed 18 patents, has $1.7 million in seed funding from some fancy names and is closing a Series A, and hopes to have a product on the market in two years. We’re skeptical; if you know the physics and can discuss, by all means leave a comment.