The proposed climate fix tech companies just spent millions on? Rocks.

To effort to counteract the interaction their contamination has connected the climate, Google and different large companies person bought into a program to trap c dioxide utilizing rocks. They precocious announced multimillion dollar deals with a Sheryl Sandberg-backed startup called Terradot.

Google, H&M Group, and Salesforce are among a gaggle of companies that collectively agreed to wage Terradot $27 million to region 90,000 tons c dioxide from the atmosphere. The deals were brokered by Frontier, a carbon removal initiative led by Stripe, Google, Shopify, and McKinsey Sustainability.

Separately, Google announced its ain woody to acquisition an further 200,000 tons of c removal from Terradot. Both companies declined to accidental however overmuch that woody is worth. If the outgo is akin to the Frontier statement — astir $300 per ton of CO2 captured — it could adhd up to $60 million, though Google says it expects the terms to travel down implicit clip for this larger deal.

Google says it’s the biggest acquisition yet of c removal done enhanced stone weathering (ERW), the strategy Terradot uses to effort to dilatory clime change. It’s a comparatively low-tech maneuver for taking c dioxide retired of the ambiance that present has important backing from immoderate large names.

“I mean, it’s a large deal, says Oliver Jagoutz, a prof of geology astatine MIT. “I deliberation it should spell a small retired of the world satellite into the concern world. And I privation these guys each the best.”

Terradot grew retired of a probe task astatine Stanford, wherever CEO James Kanoff and CPO Sasankh Munukutla were undergraduate students astatine the time. Shortly earlier graduating successful 2022, they co-founded the institution on with Kanoff’s erstwhile professor, Scott Fendorf, who is present Terradot’s main idiosyncratic and method advisor.

Before starting that probe project, Kanoff had concisely dropped retired of Stanford during the covid pandemic to co-found a nonprofit called the Farmlink Project that connects nutrient banks to farms with excess produce. Kanoff met Sandberg done that initiative, which is however helium was capable to get the erstwhile Facebook COO’s enactment for Terradot arsenic an investor.

“I’ve known James, the CEO, since agelong earlier this institution started,” Sandberg said successful a press release. “These are proven leaders, which is uncommon to find successful an early-stage company. They person the drive, the close exertion and a beardown absorption connected execution to succeed.”

Enhanced stone weathering attempts to velocity up a natural process that mightiness different instrumentality thousands of years. Rainfall people “weathers” oregon breaks down rock, releasing calcium and magnesium and triggering a chemic absorption that traps CO2 successful h2o arsenic bicarbonate. Groundwater carrying that bicarbonate yet makes its mode to the ocean, which stores the c and keeps it retired of the atmosphere.

Accelerating the process, successful theory, is simple: crush up stone and dispersed it retired implicit a ample area, expanding the aboveground country of exposed stone that reacts with CO2. Terradot has a 2029 deadline to marque bully connected the 90,000-ton Frontier deal. It’s expected to seizure the further 200,000 tons for Google by the aboriginal 2030s.

Terradot takes basalt from quarries successful confederate Brazil to adjacent farms. Farmers tin usage the finely-ground basalt to negociate the pH of soil, and c removal is simply a bonus. Terradot struck up a concern with Brazil’s cultivation probe bureau (EMBRAPA), allowing the startup to usage this strategy connected much than 1 cardinal hectares (roughly 2,471,054 acres) of land. Another perk successful Brazil is simply a hot, humid clime that besides helps to velocity up the weathering process.

The tricky portion volition beryllium trying to number however overmuch CO2 Terradot really manages to trap. Google admits this successful its announcement:

Terradot says it’ll instrumentality ungraded samples to measure however overmuch CO2 is captured based connected however the stone degrades implicit time. But it’s harder to fig retired however overmuch calcium, magnesium, and bicarbonate makes it to the water to permanently sequester CO2. Fertilizer successful the ungraded tin besides potentially bounds however overmuch c is captured done enhanced stone weathering.

“How overmuch they sequester is inactive the outstanding question,” Jagoutz says. But helium doesn’t deliberation that uncertainty needs to halt trials successful the existent world. “I besides think, wherefore not try? ... I don’t deliberation we person the luxury to overthink it close now.”

Carbon removal, astatine best, is conscionable an effort to counteract immoderate of a company’s bequest of contamination portion they marque that vigor transition. And adjacent though Google says it signed the biggest ERW woody to date, 200,000 tons of c removal is inactive a tiny fraction of the 14.3 cardinal metric tons of c dioxide contamination it was liable for past year.

“It’s precise wide that this is not a substitute for emissions reductions astatine each ... we request some of these tools,” Kanoff says. “Any of the partners we’re adjacent reasoning astir moving with, they person immoderate of the astir assertive emanation simplification strategies of immoderate of the companies truly successful the world. And those are the groups that we truly privation to spouse with to beforehand c removal.”