How could space-based solar power stations beam energy to Earth?

The answer

Space-based solar power (SBSP) would collect solar energy in geostationary orbit, where sunlight is available 99% of the time at roughly 1,366 watts per square meter - about 5-10 times more intense than on Earth's surface. The energy would be converted to microwaves and beamed to terrestrial rectennas (rectifying antennas). In 2023, Caltech's MAPLE experiment on the Space Solar Power Demonstrator successfully transmitted solar energy wirelessly from orbit to a rooftop receiver for the first time. The UK Space Energy Initiative published a roadmap for a 2-GW orbital solar farm by the 2040s. China plans to build a megawatt-level test station by 2035. The main challenges include the massive cost of launching thousands of tonnes of hardware to orbit and building kilometer-scale structures in space. However, Starship's projected cost reductions could make SBSP economically competitive with terrestrial renewables within decades.