Chinese scientists have successfully tested a ground-based system capable of wirelessly transmitting power to multiple moving targets simultaneously, marking a major breakthrough in the global race to harness solar energy from space.

The milestone was achieved by the "Sun Chasing project" research team led by Duan Baoyan, a member of the Chinese Academy of Engineering and a professor at Xidian University in Shaanxi province.

The breakthrough brings the long-envisioned concept of orbital "wireless charging stations" closer to reality.

The system successfully delivered 1,180 watts of output power over a distance of more than 100 meters to multiple moving targets. The successful demonstration of "one-to-many" dynamic wireless power transmission pushes the technology closer to practical engineering applications.

Duan compared the space solar power station to a wireless charging post positioned in a predetermined orbit.

Space-based solar power is widely regarded as a promising clean energy solution in the future. In orbit, free from atmospheric interference and the cycle of night and day, such systems can collect sunlight continuously. However, because running physical cables down to Earth from a geostationary orbit, which lies 36,000 kilometers above the planet, or between spacecraft is impossible, scientists must rely on microwave wireless power transmission. The process converts electricity into microwaves, beams them across vast distances, and then converts them back into usable direct current electricity upon arrival.

Currently, many small satellites in low-Earth orbit can generate power for only about 60 minutes during each 96-minute orbit. For the remaining time, they remain in the Earth's shadow and rely entirely on onboard batteries. A space-based charging network would reduce the dependence on individual solar panels, allowing satellites to recharge in orbit, Duan said.

To achieve this, Duan's team proposed the OMEGA design in 2014, which uses unique spherical principles to concentrate sunlight. In June 2022, the team built what it described as the world's first full-link ground validation system, successfully testing every stage of the process — from capturing sunlight and converting it into electricity, to transforming the electricity into microwaves, transmitting them before converting them back into electricity on the ground.

The team's latest iteration, dubbed Distributed OMEGA, addresses the complex engineering challenge of building and maintaining massive power grids in space. By focusing on modularity, the system uses standardized, independent components that can be assembled or replaced in orbit like building blocks.

"Unlike the previous design that utilized a complete spherical condenser to collect sunlight — where encountering space debris could render the entire system unusable — dividing it into multiple small-aperture spherical concentrators and adopting a 'formation flying' approach ensures that even if individual units are damaged, the overall performance remains almost unaffected, thereby improving system reliability," said Li Xun, a professor at Xidian University's School of Mechano-Electronic Engineering.

Li added that this also allows for reducing the voltage of each unit, improving the engineering feasibility.

Recent test data highlighted significant performance improvements over the 2022 baseline. At a distance of more than 100 meters, the system achieved a 20.8 percent direct current-to-direct current transmission efficiency, up from 15.05 percent in 2022. The beam collection efficiency reached 88 percent, ensuring that the microwave beam remained tightly focused on its target.

Li said that the performance is "world-leading", contributing to the improvement of high-precision sun tracking to guarantee energy collection at the source, a precise closed-loop control system to accurately direct the beam from the transmitter to the receiver for higher collection efficiency, and a highly integrated design to minimize link losses.

"Different from chips, there is no technology blockade among nations when it comes to building space solar power stations. Under a similar level of industrial capability, continuously raising the bar can only be achieved through technological iteration," said Duan Xuechao, deputy dean of the School of Mechano-Electronic Engineering.

Crucially, the team also solved the tracking precision challenge required to power moving objects. In a simulated trial, a drone flying at 30 km/h successfully received a stable 143 watts of power from 30 meters away. This capability is considered essential for space applications, where satellites and orbital stations are constantly moving relative to one another.

An expert panel organized by the Shaanxi Provincial Technology Transfer Center evaluated the project and concluded that the results had reached a world-leading level, with broad prospects for engineering and industrial applications.

Duan said that the team will continue to address key challenges. This includes adapting systems from ground-based validation to actual space environments, improving wireless power transmission efficiency over long distances, and achieving ultra-precise beam steering control while the satellite is moving at high orbital speeds.