The U.S. Defense Advanced Research Projects Agency (DARPA) has set a new benchmark in wireless power transmission through its Persistent Optical Wireless Energy Relay (POWER) program.
In its latest demonstration, DARPA managed to transmit 800 watts of power over a distance of 1.6 kilometers (approximately 1 mile) using a laser-based system.
This significantly exceeds previous wireless power efforts, both in scale and practical efficiency. The experiment was conducted at the U.S. Army's Blossom Point test facility in Maryland.
-- How the Technology Works --
The POWER program uses high-energy infrared lasers to beam power across distances to remote receivers.
The core technology demonstrated was the Power Transmitting Optical System (PTOS) and Power Receiver Array Demonstrator (PRAD). The PRAD is a compact spherical receiver that focuses the laser through a small aperture using a parabolic mirror.
The laser light then strikes an array of photovoltaic (PV) cells, converting it back into usable electricity. This setup enables efficient, targeted wireless energy delivery using line-of-sight laser transmission.
-- Efficiency and Current Limitations --
During the test, the system achieved 20% end-to-end efficiency—meaning that 20% of the laser’s original energy was converted back into electricity at the receiving end.
While this may seem low, it is a notable accomplishment given the challenges of long-distance, high-power laser transmission. Improving efficiency remains a major goal in future phases.
The team believes that as this technology matures, it could support higher power levels and longer distances with better conversion rates.
In its latest demonstration, DARPA managed to transmit 800 watts of power over a distance of 1.6 kilometers (approximately 1 mile) using a laser-based system.
This significantly exceeds previous wireless power efforts, both in scale and practical efficiency. The experiment was conducted at the U.S. Army's Blossom Point test facility in Maryland.
-- How the Technology Works --
The POWER program uses high-energy infrared lasers to beam power across distances to remote receivers.
The core technology demonstrated was the Power Transmitting Optical System (PTOS) and Power Receiver Array Demonstrator (PRAD). The PRAD is a compact spherical receiver that focuses the laser through a small aperture using a parabolic mirror.
The laser light then strikes an array of photovoltaic (PV) cells, converting it back into usable electricity. This setup enables efficient, targeted wireless energy delivery using line-of-sight laser transmission.
-- Efficiency and Current Limitations --
During the test, the system achieved 20% end-to-end efficiency—meaning that 20% of the laser’s original energy was converted back into electricity at the receiving end.
While this may seem low, it is a notable accomplishment given the challenges of long-distance, high-power laser transmission. Improving efficiency remains a major goal in future phases.
The team believes that as this technology matures, it could support higher power levels and longer distances with better conversion rates.
The U.S. Defense Advanced Research Projects Agency (DARPA) has set a new benchmark in wireless power transmission through its Persistent Optical Wireless Energy Relay (POWER) program.
In its latest demonstration, DARPA managed to transmit 800 watts of power over a distance of 1.6 kilometers (approximately 1 mile) using a laser-based system.
This significantly exceeds previous wireless power efforts, both in scale and practical efficiency. The experiment was conducted at the U.S. Army's Blossom Point test facility in Maryland.
-- How the Technology Works --
The POWER program uses high-energy infrared lasers to beam power across distances to remote receivers.
The core technology demonstrated was the Power Transmitting Optical System (PTOS) and Power Receiver Array Demonstrator (PRAD). The PRAD is a compact spherical receiver that focuses the laser through a small aperture using a parabolic mirror.
The laser light then strikes an array of photovoltaic (PV) cells, converting it back into usable electricity. This setup enables efficient, targeted wireless energy delivery using line-of-sight laser transmission.
-- Efficiency and Current Limitations --
During the test, the system achieved 20% end-to-end efficiency—meaning that 20% of the laser’s original energy was converted back into electricity at the receiving end.
While this may seem low, it is a notable accomplishment given the challenges of long-distance, high-power laser transmission. Improving efficiency remains a major goal in future phases.
The team believes that as this technology matures, it could support higher power levels and longer distances with better conversion rates.
