A wireless power system

Scientists at Stanford University in the U.S., have designed a charging system that uses highly efficient magnetic fields to transmit electrical currents between metal coils spaced several meters, without using a single cable.

The long term goal of the research is to apply this system to transfer power wirelessly to the roads. Thus, when electric cars circulate through the highways, your batteries will be recharged, without requiring vehicles to stop.

According to Stanford University in a statement, in the future, this technology could dramatically increase the rate of conduction of electric vehicles and transform travel by highway.

Thus, could be resolved one of the main problems with electric cars: limited autonomy. Generally, these vehicles can travel less than 160 miles after each refueling, and its batteries take to recharge several hours.

The ability to be recharged while driving exceed this limitation, it would allow a drive for an indefinite period of time, without having to stop. In fact, at the end of each trip, the batteries would be fuller than at the time of departure.

In 2007, researchers at the Massachusetts Institute of Technology (MIT) used magnetic resonance coupling to power a 60 watt bulb.

In experiments, it was shown that electricity could be transferred between two fixed coils, separated by a distance of six feet, even when standing between two obstacles.

The tests also found that the magnetic fields did not affect the people, though they be rooted in the middle of the coils, which is important in terms of security.

MIT researchers created after these findings, the company WiTricity, which is developing a charging system capable of transferring wireless about three kilowatts of electricity to a vehicle parked in a garage or street.

The researchers aim to ensure that this source of electricity will not affect drivers and passengers or electronic devices of vehicles that are responsible for controlling, among other factors, air conditioning or power steering.

Scientists have also begun to study the optimal design of electric road transmitters, and determine whether the metals used as reinforcement in the highways could reduce the electrical efficiency of the network of coils.

According to Fan: "We have an opportunity to rethink how to deliver electricity to our cars, homes and work. We are accustomed to thinking in such terms of supply cables and plugs. Imagine that instead of cables and plugs, can transfer electricity through a vacuum. Our work is a step in that direction. "The results of detailed research have appeared in the journal Applied Physics Letters (APL).