Early power beaming demonstrations took place in 1975, the first in Waltham, Massachusetts in the laboratories of Raytheon, and the second at the Goldstone Station of the Nasa Deep Space Network in California. Those were the two most important such demonstrations in history, Jaffe told his audience.

“The third one you're going to see in a few minutes,” he said.

At NRL, Jaffe has been conducting space-based solar energy research for more than a decade, focusing in part on transmitting solar energy from space to Earth. One of the biggest challenges he and others working on the problem have faced is the enormous sizes required for the transmitter and the receiver.

“Radio waves have a fairly long wavelength and in order to steer them effectively ... you need a really big antenna,” he explained. “But as the wavelength gets shorter, as it does for infrared light, which is what we're using here today, the transmitter and receiver can be much, much smaller.”

The photovoltaics of the receiver are similar to those of a typical solar panel, Jaffe said, though they are designed to be sensitive to the single color of light of the laser, rather than the broad spectrum of sunlight. They convert that particular wavelength with much greater efficiency than would a regular solar photovoltaic.

Standing beside a monitor showing a live feed from an expensive, highly specialized camera that captured the invisible laser beam as a purple light shooting across the dark expanse of the basin, Jaffe called the power beaming system a remarkable new capability. He said it could unlock all kinds of amazing possibilities for the Department of Defense and the private sector.

Imagine using it to send power to locations that are remote, hard to reach or lack infrastructure, he suggested. Another potential application of the technology would be powering electric unmanned aerial vehicles (UAVs), whose flight time is currently severely limited by their on-board battery life. The third phase of the PTROL project will involve using power beaming to send power to a flying UAV.

“If you have an electric drone that can fly more than an hour, you're doing pretty well,” Jaffe said. “If we had a way to keep those drones and UAVs flying indefinitely, that would have really far-reaching implications. With power beaming, we have a path toward being able to do that.”