Scientists at Japan’s space agency successfully transmitted energy over a distance wirelessly, in what officials called a key step in space exploration that could make solar power generation in space a possibility, Japan Aerospace Exploration Agency (JAXA) said Thursday.

Researchers used microwaves to transmit 1.8 kilowatts of power accurately to a receiver 55 meters (170 feet) away. A JAXA spokesman said the distance and power were small, but the technology could one day be used to tap the prodigious solar energy available in space, Agence France-Presse reported.

"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," he said.

He added that JAXA had been working on space solar power for years, but the technology remained highly experimental and it "maybe in the 2040s or later" before its practical application is seen. "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," the spokesman said.

In an interview on the JAXA website, Yasuyuki Fukumuro, space solar power systems researcher at the agency, said the ultimate goal is to use a microwave transmitting satellite to hit a radar dish 3 kilometers (1.9 miles) in diameter from an altitude of 36,000 kilometers (22,369 miles). “In my opinion, Japan currently has the most advanced technology to do this,” he said.