Nihon Dengyo Kosaku and Volvo Technology Japan succeeded in wirelessly transmitting more than 10kW of electricity to a distance of 4m or more.
Nihon Dengyo Kosaku and Volvo Technology Japan succeeded in wirelessly transmitting more than 10kW of electricity to a distance of 4m or more.
[Click to enlarge image]
The rectenna was made by combining eight rectennas whose output is about 1.3kW each.
The rectenna was made by combining eight rectennas whose output is about 1.3kW each.
[Click to enlarge image]

Nihon Dengyo Kosaku (Dengyo) Co Ltd and Volvo Technology Japan developed a wireless power transmission system for electric vehicles (EVs).

This time, they employed a method that uses microwaves and succeeded in wirelessly transmitting more than 10kW of electricity to a distance of 4-6m.

The system was realized by developing a high-efficiency "rectenna." A rectenna is a device made by combining an antenna and a rectifier, and it converts electromagnetic waves into direct-current electricity. This time, Dengyo and Volvo Technology Japan developed a rectenna that has a high output power of 10kW and a high conversion efficiency of about 84%. The efficiency is twice as high as those of the rectennas that Dengyo developed in the past.

The output power per area is 3.2kW/m2 or higher, which Dengyo claims is the "world's highest output." The frequency of the microwave is 2.45GHz.

Volvo Technology Japan was established by Sweden-based AB Volvo in 2012 in Tokyo as its R&D base in Asia. The Volvo Group plans to apply the newly-developed wireless power transmission technology to commercial vehicles such as buses and trucks, Volvo Technology Japan said.

動画 The experiment (0:51)

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