Solaris: ESA Says Space-Based Solar Power Is a Real Option

But a vast fleet of super-lightweight orbiting mirrors joined up to direct sunshine onto solar farms on the ground might be made to work. (Of course their weight in orbit is zero. What matters was their weight on the launch pad.)

The mirrors are optically flat, but mass only milligrams. Very gently unfolded and joined together by thousands of mechanical spiders, they focus sunlight onto another, much smaller mirror many thousands of miles away that rotates to redirect the light to a ground-based array as it turns past. This mirror has many faces (6?) so that as it rotates and the ground target finally turns out of view, the next face picks out another farm to take its light.