US Military Funds Laser Power Beaming to Keep Drones Flying Indefinitely

What is laser power beaming for drones?

Laser power beaming is a wireless energy transfer method that uses directed lasers to charge a drone's battery while it is in flight. PowerLight's Aerial ReCharge (ARC) system employs a ground-based transmitter that tracks the drone and beams power to a receiver mounted on the aircraft, enabling continuous operation without landing.

Unlike inductive charging used in smartphones, which relies on electromagnetic fields over short distances, optical power beaming uses laser light to transmit energy over much greater ranges. This allows the ARC system to recharge drones even when they are moving, as the transmitter autonomously follows the UAV.

The technology is designed to work with various drone classes, including Group 2 fixed-wing platforms and larger aircraft carrying heavy sensor or effects payloads. PowerLight says the system can also recharge a drone's payload if needed.

How does the Aerial ReCharge system work?

The Aerial ReCharge system consists of a ground-based power beaming transmitter and a receiver on the drone. The transmitter directs a laser beam at the receiver, which converts the light into electrical energy to charge the drone's battery. The transmitter autonomously tracks the drone to maintain a continuous power link.

PowerLight's ARC is capable of delivering kilowatt-class power to drones at distances up to 5,000 feet. This allows drones to remain on station for extended periods without returning to base for battery swaps, which saves time and reduces risk in contested environments.

The system was demonstrated with a Kraus Hamdani Aerospace K1000ULE drone equipped with a power beaming receiver. The US Department of War's Operational Energy - Innovation Directorate awarded the contract for further development at Shaw Air Force Base in South Carolina.

1. A ground-based transmitter emits a laser beam.
2. A receiver on the drone captures the laser light.
3. The receiver converts light into electrical energy.
4. The energy charges the drone's battery or payload.
5. The transmitter tracks the drone to maintain power delivery.

Why does the US military want laser-powered drones?

The US military aims to extend drone mission endurance and reduce operational downtime. By recharging drones in flight, the need to land and swap batteries is eliminated, allowing for continuous surveillance or combat support. This is particularly valuable in contested environments where landing poses risks.

Chris DePuma, OE-I Combat Power Portfolio Lead, stated that power beaming means 'more time on mission and less time on the ground.' The ARC system reduces the logistical burden of battery management and allows drones to stay airborne almost indefinitely.

The technology also has potential beyond military use. PowerLight CEO Tim Jenks noted that power beaming can be applied from ground-to-ground, ground-to-air, air-to-air, and space-to-space, indicating broad future applications.

What are the challenges and limitations of laser power beaming?

Laser power beaming faces challenges such as atmospheric interference, safety concerns, and efficiency losses over distance. While the ARC system can deliver kilowatt-class power at 5,000 feet, factors like weather and obstacles can affect beam quality. Safety protocols are essential to prevent eye damage or interference with other aircraft.

PowerLight has not disclosed specific efficiency rates or safety measures, but the technology is being developed under military oversight, which likely addresses these issues. The system's autonomy helps maintain alignment, but adverse conditions may still limit effectiveness.

As with any emerging technology, cost and scalability remain open questions. The DOW contract suggests confidence in the approach, but widespread deployment will depend on further testing and refinement.

Bottom line

The US military's investment in PowerLight's laser power beaming marks a significant step toward drones that can stay airborne almost indefinitely. While challenges remain, the potential to reduce downtime and risk is substantial. Keep an eye on further tests and possible civilian applications that could reshape drone operations.