Governments and private companies are racing to master the art of space-based refueling, whether the goal is recharging satellites or reloading spacecraft with a full tank of fresh chemical propellant. U.S. Space Force, to cite just one example, has awarded tens of millions of dollars to private contractors promising orbital fueling stations capable of delivering hydrazine to its space-based platforms. Now, researchers with China’s Xidian University have announced progress in their plan to develop a far cleaner and more sustainable alternative: a space-based solar power plant capable of remotely recharging drones while these uncrewed aerial platforms are still in flight. According to an announcement Monday by China’s official state news site, Xinhuanet, scientists and engineers with the university’s “Sun Chasing” project managed to deliver 143 watts of stable power from their prototype solar platform to a drone flying at roughly 19 miles per hour (30 kilometers per hour) from 98 feet (30 meters) away. And the device apparently fared even better delivering wireless electricity to stationary targets, Xinhuanet reported. “In recent tests, the system achieved a wireless power transmission efficiency of 20.8% from direct current to direct current over a distance of [328 feet] 100 meters,” the news agency said. “It delivered 1,180 watts of power.”