With Bill Gates retreating from his high-profile climate crusade, the stage has opened for more unconventional actors to step into the planetary arena. Enter Elon Musk, the chief executive of SpaceX and self-styled architect of humanity’s future in space.
This week, Musk floated an audacious vision: a vast swarm of orbiting satellites, not merely to beam internet or data, but to harvest solar energy and regulate how much sunlight reaches Earth. On Monday, he wrote on his platform X:
A large solar-powered AI satellite constellation would be able to prevent global warming by making tiny adjustments in how much solar energy reached Earth.
It is not an isolated musing. Musk already commands more than 8,000 satellites in orbit, making SpaceX the single largest operator in low Earth orbit. His company is also deeply integrated with the U.S. defense and intelligence establishment, providing secure communications and reconnaissance support. And as one of Donald Trump’s biggest donors and technology contractors, Musk stands at the intersection of private ambition and state power.
The announcement reignited debate over geoengineering — also known as solar radiation modification (SRM) — a highly controversial concept to cool the planet by deflecting sunlight. Many observers, weary of climate-doomsday narratives and wary of billionaire “saviors,” have urged Musk to refrain from “playing God.”
The Technical Blueprint
Musk’s posts were brief, but behind them lie two vast engineering ambitions — one focused on solar power, the other on climate control. To most readers, it may sound like science fiction, yet the ideas are grounded in real, if speculative, physics.
Satellites to Capture the Sun
The first part of Musk’s plan involves satellites that would collect solar energy directly in space. He mentioned harnessing 100 gigawatts per year through an array of orbiting satellites launched by SpaceX’s upcoming Starship rocket. For perspective, one gigawatt equals the output of a large nuclear power plant.
Space-based solar power isn’t new, but it has never advanced beyond early experiments. The principle is simple: Sunlight in space is stronger because it’s unfiltered by Earth’s atmosphere. In orbit, solar panels could generate power 24 hours a day, unaffected by clouds or night.
The challenge is transmitting that energy back to Earth. Musk’s vision likely involves converting solar power into microwave or laser beams, then directing them to ground-based receivers. In theory, it could supply clean electricity to power grids or floating data centers. In practice, it would require precise targeting and vast safety controls to prevent energy loss or harm.
Musk also hinted at an even grander future — moon-based factories building AI satellites directly on the lunar surface. At that scale, he suggested, new satellites could generate hundreds of terawatts of power. That would surpass humanity’s current total energy use of about 17-20 terawatts.
Hellbound and Down 