Canadian Researchers Create Wireless Charger For Electric Cars

An anonymous reader writes "University of British Columbia researchers have developed a wireless charging system for electric cars. It involves a spinning magnet beneath the parked vehicle which turns another magnet in the underside of the car. Charging takes four hours and is about 90% as efficient as plugging in. From the article: '"One of the major challenges of electric vehicles is the need to connect cords and sockets in often cramped conditions and in bad weather," says David Woodson, managing director of UBC Building Operations. "Since we began testing the system, the feedback from drivers has been overwhelmingly positive." Four wireless charging stations have been installed at UBC's building operations parking lot. Tests show the system is more than 90 per cent efficient compared to a cable charge. A full charge takes four hours and enables the vehicle to run throughout an eight-hour shift.'"

Comments

Existing tech

[trout007]

This is used all of the time in pumps where you don't want a dynamic seal. You have permanent magnets spun by a motor and inside a sealed case the pump is coupled by a magnetic field.

http://www.proconpumps.com/brands/Magnetically-Coupled-Pump-(Sealless).html

Re:efficiency: 90% of cable?

[Anonymous Coward]

Let's see if you're right. A Tesla Roadster has a 50kWh battery. Charging that in 4 hours requires 12500W of power. 10% of that is lost compared to the cable charger. That's 1.25kW of heat in addition to the heat from the inefficiencies of the rest of the charging system and the battery. That's in heater territory, but not enough to significantly heat an uninsulated garage. Problems with molten ice and snow can't be much different from parking a car with a warm engine.