updated 03:45 pm EDT, Fri July 6, 2012
Japanese researchers show electricity transmission through 10cm of concrete, tires, axle
Researchers at the Toyohashi University of Technology have successfully demonstrated that they've sent electricity through a layer of 4-inch thick concrete. The demonstration took place at the Wireless Technology Park (WTP) 2012, and the transmission also went through the car tires, rims, and the axles. The idea is that eventually, electric roads could power electric cars, without the cars needing to carry expensive and heavy batteries.
The inductive coupling method allowed between 50 and 60W of energy, with an efficiency of greater than 80 percent, Tech-On reported. The kind of concrete used was the same one as is used for public roads in Japan. The demo involved a simple light bulb coming on attached between the car's tires and axles.
The researchers, headed up by Takashi Ohira, the professor at the university's Department of Electrical and Electronic Information Engineering, said they believe they can eventually send the power through 20cm or even thicker concrete. To achieve this, however, electrical power needs to be increased by a factor of 100. The hardware needed for this is relatively inexpensive, however, and there are no other major obstacles.