China makes a breakthrough in space-based solar power generation

Xi’an, China — Chinese scientists have taken a major step toward developing space-based solar power plants that could one day beam energy back to Earth or to spacecraft. A research team from Xidian University in Shaanxi Province, northwestern China, made significant progress in the Sun Chasing project, or Zhuri in Mandarin. The team has developed a ground-based test system for wireless power transmission capable of charging several moving targets simultaneously. In recent tests, the system achieved a wireless power transmission efficiency of 20.8 percent from direct current (DC) to DC at a distance of 100 metres, delivering 1,180 watts of power. The researchers have also built a wireless charging system for drones. In one test, a drone flying at 30 kilometres per hour was able to receive a stable 143 watts from a distance of 30 metres. Space-based solar power plants operate as the name suggests: an enormous array of solar panels placed in outer space. The plant would collect sunlight in space, where the Sun is constantly shining, and then convert that energy into microwaves or lasers to be beamed back to Earth or directly to satellites and space vehicles. This method could address two major challenges: supplying uninterrupted power for space missions and addressing the energy crisis on Earth. Previously, in 2018, the research team launched the first phase of the Sun Chasing project to build a ground test facility. Then in June 2022, they completed a ground validation system with full link and the world’s first end-to-end system for space-based solar power. Now the team has moved to the second phase. The current aim is to tackle the challenges of generating high power in space and transmitting it efficiently over long distances. According to Duan Baoyan, a specialist at Xidian University and an academician of the Chinese Academy of Engineering, the latest breakthroughs include improvements in the efficiency of solar energy collection and conversion, higher precision in microwave beam control to reduce energy losses, and the manufacture of lighter transmitter and receiver antennas, which are crucial for space applications. The team has also solved the problem of supplying power to multiple moving targets simultaneously using a single transmitter. This means that in the future, a single space-based power plant could supply electricity to several satellites or vehicles on Earth at once, Duan added. Duan noted that there is still a long way to go before space-based solar power becomes commercially viable. The next step, he said, is orbital testing. He hopes to contribute China’s knowledge and solutions to support the global energy transition and sustainable development.