A research team led by Duan Baoyan of the Chinese Academy of Engineering reported major progress on Zhuri, the country’s space based solar power program, whose name translates roughly to Chasing the Sun. The headline number is 1,180 watts delivered wirelessly to multiple moving targets at a range of more than 100 meters.
The numbers that matter
20.8 percent DC to DC efficiency across a distance over 100 meters. That is electricity in on one end and electricity out on the other, with the microwave conversion, transmission, capture and rectification losses all counted. The same program measured 15.05 percent in 2022, so this is a 38 percent relative improvement in four years.
88 percent beam collection. Nearly nine tenths of the transmitted energy landed inside the receiving aperture. This is the safety number as much as the efficiency number. A beam that stays where you aimed it is a beam you can regulate.
143 watts to a drone at 30 meters, while the drone was flying at 30 kilometers per hour. Tracking a moving receiver and holding a stable delivery is meaningfully harder than hitting a fixed panel, and it is the capability that turns this from a lab curiosity into something deployable.
Why the efficiency figure is the whole story
Twenty percent sounds unimpressive until you compare it against what it is replacing. For a satellite that currently cannot generate enough power to run its own payload, 20 percent of a beam is infinitely better than 100 percent of nothing.
For grid power it is a different story. Transmission losses on a conventional line run around 5 percent. Nobody replaces a wire with something four times worse. That is why every credible near-term application is somewhere a wire cannot go: orbit, a moving aircraft, a remote sensor, the lunar surface.
Tesla proposed this in 1901
The specific mechanism is different. Tesla’s Wardenclyffe design used earth conduction and resonant coupling, not focused microwave beams, and on that point he was simply mistaken about how the planet behaves.
The premise holds up perfectly. Generate power where generating it is easy, move it through open space, collect it where it is needed, skip the copper entirely. That was the pitch to J.P. Morgan. It took 125 years, solid state amplifiers and phased array beam steering, but the pitch was sound.
China is targeting an orbital demonstration before the end of the decade. Western commercial programs are on a similar timeline, and for once the constraint is not physics. It is launch cost and robotic assembly.