Google and other big corporations have partnered with a startup called Terradot to mitigate their impact on climate change. The company uses enhanced rock weathering (ERW) technology, which involves crushing rocks and spreading them out over large areas to accelerate the natural process of carbon dioxide capture.
A Multimillion-Dollar Deal
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 deal was brokered by Frontier, a carbon removal initiative led by Stripe, Google, Shopify, and McKinsey Sustainability.
Google’s Additional Deal
Separately, Google has announced its own deal with Terradot to purchase an additional 200,000 tons of carbon removal. While Google declined to disclose the cost of this deal, if it is similar to the Frontier agreement ($300 per ton of CO2 captured), it could add up to $60 million.
Enhanced Rock Weathering: A Low-Tech Solution
Enhanced rock weathering attempts to speed up a natural process that takes thousands of years. Rainfall naturally "weathers" or breaks down rocks, releasing calcium and magnesium and triggering a chemical reaction that traps CO2 in water as bicarbonate. Groundwater carrying this bicarbonate eventually makes its way to the ocean, where it is stored.
Terradot uses basalt from quarries in southern Brazil to accelerate this process. The finely ground basalt is spread over large areas of land, increasing the surface area exposed to carbon dioxide. Farmers can use this rock to manage soil pH, and carbon removal is a bonus.
Partnership with Brazil’s Agricultural Research Agency
Terradot has partnered with Brazil’s agricultural research agency (EMBRAPA), allowing them to use their ERW strategy on over 2 million hectares of land. The hot and humid climate in Brazil also speeds up the weathering process.
Challenges Ahead: Measuring CO2 Capture
While Terradot claims that their technology can capture significant amounts of carbon dioxide, measuring this effect is a tricky task. Google admits that it’s hard to measure with precision how much CO2 is removed from the atmosphere using ERW. However, they believe that deploying this approach widely in the real world will help develop more rigorous measurement tools.
Terradot plans to take soil samples to assess how much carbon dioxide is captured based on how the rock degrades over time. But it’s harder to determine how much calcium, magnesium, and bicarbonate makes it to the ocean to permanently sequester CO2. Fertilizer in the soil can also limit how much carbon is captured through enhanced rock weathering.
The Outstanding Question: How Much Carbon is Captured?
According to Dr. Jagoutz, a geologist at Harvard University, "how much they sequester is still the outstanding question." However, he doesn’t think that uncertainty should stop trials in the real world. "I also think, why not try?" he says.
The Limitations of Carbon Removal
While carbon removal can help mitigate climate change, it’s essential to note that it’s not a substitute for emissions reductions. Google’s own data shows that their carbon footprint has grown as they build out energy-hungry AI data centers. Switching to clean energy is the only effective way to stop climate change.
Carbon removal is at best an attempt to counteract some of a company’s legacy of pollution while making that transition. Even with Google’s largest ERW deal, 200,000 tons of carbon removal is still a small fraction of their annual carbon dioxide emissions (14.3 million metric tons).
Conclusion
Google and Terradot’s partnership is a step in the right direction for mitigating climate change. However, it’s essential to remember that carbon removal should not be seen as a substitute for emissions reductions. We need both tools to combat climate change.
Terradot’s ERW technology has potential, but measuring its effectiveness will be crucial to determining its success. As Dr. Jagoutz notes, "we don’t have the luxury to overthink it right now." It’s time to try and deploy this approach widely in the real world to develop more rigorous measurement tools.
Related Articles
- Google’s future data centers will be built next to solar and wind farms
- Google inks nuclear deal for next-generation reactors
- Carbon dioxide emissions from fossil fuels are already making heatwaves, droughts, wildfires, storms, and other climate disasters more dangerous.
