The unit has yet to actually send power directly back to Earth, but that technology has already been proven. If the project develops into huge kilometers-wide space solar antennae, it could beam microwaves that would then be converted into fuel-free electricity to any part of the planet at a moment’s notice.
Scientists working for the Pentagon have successfully tested a solar panel the size of a pizza box in space, designed as a prototype for a future system to send electricity from space back to any point on Earth.