Milestone wireless energy transfer brings us one step closer to beaming solar energy from space

In what is being heralded as a major success in wireless power transfer, Tokyo-based scientists from Japan’s NASA-equivalent — the Japan Aerospace Exploration Agency (JAXA) — have successfully transferred 1.8 kilowatts of energy across a distance of 170 feet (55 meters), enough to run an electric kettle. 

The scientists performed this feat by converting electrons into microwaves before beaming them across the designated distance to a receiver which then recreated the electrons from the microwaves. Unlike previous experiments in this domain, no other group has been able to maintain the pinpoint accuracy achieved by the JAXA group.

“This was the first time anyone has managed to send a high output of nearly two kilowatts of electric power via microwaves to a small target, using a delicate directivity control device,” explained a JAXA spokesman, adding that JAXA has been working on this experiment as part of its SSPS effort, Space Solar Power System solution for years.

Although the distance transmitted is relatively short-ranged, scientists hope that the technology will be up-scaled in the future to harness solar power from space, where it is inexhaustible, and beam in to mankind below. The primary advantage to a space-based solar energy generation system is that energy is readily available, and unaffected by the time of day or weather, in the traditional sense of the word. 

Present day orbital satellites, such as the International Space Station, have long harnessed solar energy to power their enterprise, but none are capable of transmitting this energy down to earth; JAXA hopes microwave transmissions hold the key to the sustainable energy model of the future. 

But let’s not get a head of ourselves, given that the longest, most accurate distance on record for transmitting energy is 170 feet (55 meters), it’ll take decades before technology advances enough to transmit over a distance of 22,300 miles (36,000 km) or the distance between geostationary satellites and Earth. 

JAXA estimates this won’t be possible until at least 2040. “There are a number of challenges to overcome, such as how to send huge structures into space, how to construct them and how to maintain them,” he explains. 

Source: Phys.org