U.S. Defense Research Agency Achieves Optical Power Beaming Record

The Defense Advanced Research Projects Agency (DARPA) in the U.S. has made a significant breakthrough in optical power beaming. A recent test by the agency showed that they could send over 800 watts of power over 8.6 kilometers (5.3 miles) using a laser, which is the farthest and most powerful wireless energy transfer demonstrated so far.

Before, the longest successful transfer of significant optical power was 230 watts over 1.7 kilometers for 25 seconds. The result from DARPA is much better than the previous record. DARPA’s Tactical Technology Office said that their optical power beaming demonstration exceeded all previous records for power and distance.

The achievement was part of the Persistent Optical Wireless Energy Relay (POWER) program from DARPA, which aims to create a worldwide system that can send power quickly from energy-rich areas to places that are hard to reach or dangerous, such as battlefields or disaster zones.

The test used a laser transmitter on the ground and a special optical receiver made by Teravec Technologies, with help from Packet Digital and the Rochester Institute of Technology. The laser is guided by a parabolic mirror to the photovoltaic cells, which convert the beam into electricity. At short distances, the efficiency was 20%, and the total energy transferred was over a megajoule.

DARPA explained that the test was meant to show the design could work and reach far, not to focus on making it more efficient. In the next stages of the POWER program, the team will work on integrated relays and vertical power transmission, which will give the system more flexibility and a wider range.

This progress shows that wireless power transfer technologies are gaining more attention. Other groups, such as Space Solar in the UK and Aetherfulx in the U.S., are working on space-based power beaming systems. With DARPA bringing in more research partners, the future of remote power delivery is looking brighter.