Wednesday, 13 June 2007
We live in a wireless world of portable technologies, and yet we are still 'tethered' to the battery chargers that allow us to lead this mobile lifestyle. With limited power from batteries, and the promise of commercially available fuel cells being perpetually 5 years away, a truly wireless society seems far from reality. However, a group at MIT has been working on an alternative source of wireless electricity (WiTricity) that is generated by a non-radiative electromagnetic field oscillating at a very high frequency (MHz). A portable device, such as a laptop or mobile phone, accepts this radiation through a receiver coil that resonates at the same frequency as the emitted magnetic field. Initial experiments demonstrated that 60 Watts of power could be transferred over a distance of 2 meters. Encouraged by these preliminary results, the group at MIT are now investigating ways to increase the projection distances and efficiency while reducing the size of the receiver coils.