Space-based solar power, once for science fiction, is gaining interest.

Space-Based Solar Power enables wireless energy transfer from orbital solar arrays, using microwave beaming to rectennas on Earth, delivering clean baseload power beyond weather and night limits, as demonstrated by Caltech and NASA.

Ali Hajimiri thinks there’s a better way to power the planet — one that’s not getting the attention it deserves. The Caltech professor of electrical engineering envisages thousands of solar panels floating in space, unobstructed by clouds and unhindered by day-night cycles, effectively generating electricity from the night sky for continuous delivery, wirelessly transmitting massive amounts of energy to receivers on Earth.

This year, that vision moved closer to reality when Mr. Hajimiri, together with a team of Caltech researchers, proved that wireless power transfer in space was possible: Solar panels they had attached to a Caltech prototype in space successfully converted electricity into microwaves and beamed those microwaves to receivers, as a demonstration of beaming power from space to devices about a foot away, lighting up two LEDs.

The prototype also beamed a tiny but detectable amount of energy to a receiver on top of their lab’s building in Pasadena, Calif. The demonstration marks a first step in the wireless transfer of usable power from space to Earth, and advances in low-cost solar batteries could help store and smooth that power flow — a power source that Mr. Hajimiri believes will be safer than direct sun rays. “The beam intensity is to be kept less than solar intensity on earth,” he said.

Finding alternative energy sources is one of the topics that will be discussed by leaders in business, science and public policy, including wave energy, during The New York Times Climate Forward event on Thursday. The Caltech demonstration was a significant moment in the quest to realize space-based solar power, amid policy moves such as a proposed tenfold increase in U.S. solar that would remake the U.S. electricity system — a clean energy technology that has long been overshadowed by other long-shot clean energy ideas, such as nuclear fusion and low-cost clean hydrogen.

If space-based solar can be made to work on a commercial scale, said Nikolai Joseph, a NASA Goddard Space Flight Center senior technology analyst, and integrate with peer-to-peer energy sharing networks, such stations could contribute as much as 10 percent of global power by 2050.

The idea of space-based solar energy has been around since at least 1941, when the science-fiction writer Isaac Asimov set one of his short stories, “Reason,” on a solar station that beamed energy by microwaves to Earth and other planets.

In the 1970s, when a fivefold increase in oil prices sparked interest in alternative energy, NASA and the Department of Energy conducted the first significant study on the topic. In 1995, under the direction of the physicist John C. Mankins, NASA took another look and concluded that investments in space-launch technology were needed to lower the cost and move closer to cheap abundant electricity before space-based solar power could be realized.

“There was never any doubt about it being technically feasible,” said Mr. Mankins, now president of Artemis Innovation Management Solutions, a technology consulting group. “The cost was too prohibitive.”

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