What Could Possibly Go Wrong? Private Companies Are Doing Small-Scale Solar Engineering w/o Regulation [View all]

[hatrack]

For as little as $1, you can dim the sun — just a tiny bit — to save the world from climate change. At least, that’s the promise sold by a California start-up called Make Sunsets. Your dollar will pay for founder Luke Iseman to drive a Winnebago RV into the hills half an hour outside Saratoga, California, to release a balloon loaded with sulfur dioxide, an air pollutant normally spewed by volcanic eruptions. He and his 1,000 paying customers hope the balloon will burst in the stratosphere, releasing particles that will block sunlight and cool the planet.

Iseman’s sun-blocking activities — which aren’t officially approved by any government on Earth, but aren’t illegal under California law — are an example of a controversial tactic called “solar geoengineering.” It has been the subject of many science fiction stories, conspiracy theories and at least one U.S. spy report warning that it could spark real-world wars. And now it’s becoming a private industry. Make Sunsets has raised more than $1 million from investors and sold more than $100,000 worth of “cooling credits” to customers this year. A better-funded competitor, Stardust, has raised $75 million to develop a more sophisticated geoengineering method it says will be ready to launch by the end of the decade — although its founders vow they won’t deploy their technology unless a government hires them to do so.

The companies have sparked debate about the role private firms should play in tinkering with the global climate. Proponents say start-ups can develop a potentially world-changing technology faster than plodding university scientists; in recent years, academics studying geoengineering have tried to do basic outdoor equipment tests in Sweden and California only to face pushback and cancel their plans. “They stop. They give up,” said Maex Ament, a venture capitalist and Stardust investor. “If I’m an entrepreneur at heart, no, there is no ‘I’ll give up. Next topic.’ I’ll solve this problem, without compromising safety. There’s a different mindset.”

Opponents say profit-seeking companies have no business developing a technology designed to affect everyone on Earth, which may have unintended consequences for global weather patterns and could kill people by raising air pollution and cancer rates. “I do not trust the private sector to make good decisions for people,” said Shuchi Talati, founder of the nonprofit Alliance for Just Deliberation on Solar Geoengineering. “The whole move-fast-and-break-things ethos — I’ve seen it, and it hasn’t gone particularly well for society.”

EDIT

https://www.washingtonpost.com/climate-solutions/2025/12/03/stardust-make-sunsets-geoengineering-startups/

https://wapo.st/3MeKCkf