Have you ever imagine that you can get rid of power supply cable and make your laptop or mobile phones truly portable while you are on the move? It seems like a dream that you can charge up your laptop, mobile phone or home appliances from the air without even plugged into the power socket. But now, the invention looks set to be a great breakthrough with a demonstration of a 60W light bulb powered up from a power source located two meters away wirelessly by a group of MIT researchers.
WiTricity is based on the simple physics principal that energy can be transferred wirelessly by utilizing magnetically coupled resonance. It involved a pair of copper coils for the energy transmission. One coil, acts as the transmitter, generates a magnetic field oscillating in MHz range and on the other end, another coil act as the receiver resonates with the generated magnetic field and convert the energy back to electricity which then be used to power up the laptop continuously.
The advantage of using this method of transferring energy is it is more efficient, ~40-45% efficient and less hazardous to human body as compared to electromagnetic radiation. Furthermore, there is no line-of-sight requirement which tend to degrade the efficiency significantly with obstacles. Take a look on how the team demonstrating the setup while obstructing the line of sight between both transmit and receive coils in proof of concept stage and feature about WiTricity in BCC.