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Nihon Dengyo Kosaku and Volvo Technology Japan wirelessly transmit 10kW of electricity 4 meters using rectification of microwave signals

Tech-On. Nihon Dengyo Kosaku and Volvo Technology Japan have demonstrated the wireless transmission of 10kW of electricity a distance of 4 meters using a prototype high-efficiency rectenna—a microwave rectifying antenna that converts microwave energy into direct-current electricity.

The 10 kW rectenna was made by combining eight rectennas the output of which is about 1.3 kW each; overall efficiency of the conversion is about 84%. Dengyo announced its first rectenna product last year.

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.

The rectification of microwave signals for DC power has been researched and developed for decades for a wide range of applications, especially for satellites. (Japan is exploring the possibility of developing a Space Solar Power Station/Satellite (SPS) that would use rectennas for power transmission to Earth. Earlier post.)

The basic rectenna was patented in 1969 by William Brown.



It may cook a few birds on the way?


They've done with 10 kW over 4 meters what W.C. Brown did with 34 kW over 1 mile in 1975.


E..P - Interesting link, perhaps higher efficiency(lower cost?) and new EV/mobile recharging needs bring new attention.


I don't think microwaves are the option; from the various things demonstrated so far, I like Hanazawa's capacitive-coupled system the best (metallic car bodies shield against electric fields).  However, I'm willing to change my mind based on new data.


2.45 GHz, that's awfully close to where wifi is. I'm not sure if that's going to make people happy.

Henry Gibson

A few dozen big space parabolic antennas could allow electric airplanes to fly from Los Angeles CA to Las Vegas NV and back. The roasted birds would supply meat to the endangered eagles that survived. ..HG..


what does the 16% loss is power buy you?


16% power loss buy you is does mumbly-mumbly-bum...

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