China plans to build and launch small to medium-sized solar power stations into the stratosphere to generate electricity between 2021 and 2025. The next step will be a Megawatt-level space solar power station in 2030.
China is considering space-based construction using robots and 3D printing technology.
The International Space Station has four sets of solar arrays that generate 84 to 120 kilowatts of electricity.
No space-based solar power has been beamed to earth.
Alliant Technical Systems, ATK, was selected in 2012 by NASA's Space Technology Program under a Game Changing Technology competition for development of a promising lightweight and compact solar array structure. The MegaFlex™ engineering development unit, EDU, was tested at NASA GRC Plumbrook facility this year.
Use of high-power solar arrays, at power levels ranging from ~500 KW to several megawatts, has been proposed for a solar-electric propulsion (SEP) demonstration mission, using a photovoltaic array to provide energy to a high-power xenon-fueled engine. One of the proposed applications of the high-power SEP technology is a mission to rendezvous with an asteroid and move it into lunar orbit for human exploration (the Asteroid Retrieval mission). NASA is also exploring options for future power systems for extreme environments, including near-sun environments, solar electric propulsion, and operation on the Venus surface