The Tech Companies Spent Millions On To Fix Climate Change Are Actually Just Rocks
Google and Other Companies Bet Big on a Low-Tech Carbon Removal Strategy
Google, H&M Group, and Salesforce have collectively agreed to pay Terradot $27 million to remove 90,000 tons of carbon dioxide from the atmosphere. The deals were brokered by Frontier, a carbon removal initiative led by Stripe, Google, Shopify, and McKinsey Sustainability.
A Breakthrough in Carbon Removal
Enhanced rock weathering (ERW) is a strategy that Terradot uses to try to slow climate change. It’s a relatively low-tech tactic for taking carbon dioxide out of the atmosphere that now has significant backing from some big names. ERW attempts to speed up a natural process that might otherwise take thousands of years.
The Science Behind Enhanced Rock Weathering
Rainfall naturally "weathers" or breaks down rock, releasing calcium and magnesium and triggering a chemical reaction that traps CO2 in water as bicarbonate. Groundwater carrying that bicarbonate eventually makes its way to the ocean, which stores the carbon and keeps it out of the atmosphere.
Accelerating the Process
Crushing up rock and spreading it out over a large area increases the surface area of exposed rock that reacts with CO2. Terradot has a 2029 deadline to make good on the 90,000-ton Frontier deal. It’s supposed to capture the additional 200,000 tons for Google by the early 2030s.
A Partnership in Brazil
Terradot takes basalt from quarries in southern Brazil to nearby farms. Farmers can use the finely-ground basalt to manage the pH of soil, and carbon removal is a bonus. Terradot struck up a partnership with Brazil’s agricultural research agency (EMBRAPA), allowing the startup to use this strategy on more than one million hectares (roughly 2,471,054 acres) of land.
A Hot Climate Helps
The hot, humid climate in Brazil also helps to speed up the weathering process. However, the tricky part will be trying to count how much CO2 Terradot actually manages to trap.
Measuring Success
Google admits it’s hard to measure with precision how much CO2 this process removes from the atmosphere. But the only way to develop highly rigorous measurement tools is to deploy this approach widely in the real world. That’s why Google’s support aims to help Terradot’s solution get out of the lab more quickly.
Assessing Carbon Capture
Terradot says it’ll take soil samples to assess how much CO2 is captured based on how the rock degrades over time. However, it’s harder to figure out how much calcium, magnesium, and bicarbonate makes it to the ocean to permanently sequester CO2.
Challenges Ahead
Fertilizer in the soil can potentially limit how much carbon is captured through enhanced rock weathering. How much they sequester is still the outstanding question.
A Glimmer of Hope
However, some experts think that uncertainty shouldn’t stop trials in the real world. "I also think, why not try?" says Dr. Jagoutz. "I don’t think we have the luxury to overthink it right now."
A Small Step Forward
Google’s carbon footprints has grown as it builds out energy-hungry AI data centers. The company has recently announced plans to help develop advanced nuclear reactors and new solar and wind farms to power its data centers with carbon pollution-free electricity.
The Limitations of Carbon Removal
At best, carbon removal is just an attempt to counteract some of a company’s legacy of pollution while they make that energy transition. And even though Google says it signed the biggest ERW deal to date, 200,000 tons of carbon removal is still a small fraction of the 14.3 million metric tons of carbon dioxide pollution it was responsible for last year.
A Combination Approach
Google’s CEO says that any company looking to partner with Terradot will need to have an aggressive emission reduction strategy in place. "Any of the partners we’re even thinking about working with, they have some of the most aggressive emission reduction strategies of any of the companies really in the world," he says.
The Future of Carbon Removal
As the world continues to grapple with climate change, it’s clear that both emissions reductions and carbon removal will be necessary. But for now, Terradot’s ERW strategy is a small but promising step forward in the fight against climate change.
