This is amazing ! An US researchers looking at ways to use wi-fi as a power source.

The battery-free camera was modified so it could scavenge power from ambient wi-fi signals, store it and then use it to take photos.

The team behind the project believes its techniques will be useful for powering the many devices expected to form the “internet of things”.

Unfortunately, because wi-fi signals are broadcast in bursts across different frequencies the required amount of energy was only available too intermittently to be useful.

To fix this, the research team modified standard wi-fi hotspots and routers to broadcast noise when a channel was not being used to send data. This meant the power of the wi-fi signals stayed constant and, though low, was high enough to power some components.

Adding the noise did little to slow data rates across hotspots, said the team.

“The ability to deliver power wirelessly to a wide range of autonomous devices and sensors is hugely significant,” said a story about the research in MIT’s Technology Review. ” Powi-fi could be the enabling technology that finally brings the internet of things to life.”

Read more at BBC