$100M donation powers decade-long moonshot to create solar satellites that beam power to Earth

It sounds like a plan concocted by a supervillain, if that villain’s dastardly end was to provide cheap, clean power all over the world: launch a set of three-kilometer-wide solar arrays that beam the sun’s energy to the surface. Even the price tag seems gleaned from pop fiction: one hundred million dollars. But this is a real project at Caltech, funded for a nearly a decade largely by a single donor.
The Space-based Solar Power Project has been underway since at least 2013, when the