> Prototypes of the device are claimed to be 10 - 30 times more efficient than small wind turbines. One prototype has powered two LEDs, a radio, and a clock (separately) using wind generated from a household fan. The cost of the materials was well under US$10. $2–$5 for 40 mW is a cost of $50–$125 per watt.
https://en.wikipedia.org/wiki/Windbelt
> Prototypes of the device are claimed to be 10 - 30 times more efficient than small wind turbines. One prototype has powered two LEDs, a radio, and a clock (separately) using wind generated from a household fan. The cost of the materials was well under US$10. $2–$5 for 40 mW is a cost of $50–$125 per watt.