Toward more efficient wireless power delivery
In 2007, MIT researchers announced that they had discovered a novel way of transmitting electricity without the use of wires. Now, the researchers have demonstrated that the system’s efficiency at transmitting energy improves significantly when it is used to charge multiple devices at the same time.The new work, reported in a paper in Applied Physics Letters earlier this year, has also demonstrated a system much closer to one that could be used to power typical consumer electronic devices. In the original proof-of-concept in 2007, both the transmitter and receiver consisted of coils that were about two feet across. These two units were placed more than six feet apart and were used to light a 60-watt bulb — even with people sitting in between. But the new system uses a slightly larger transmitter, with receivers that are only about a foot across – moving closer to a size that could eventually...