Google has turned an agricultural practice into an industrial climate bet. On September 16, the company announced its largest carbon removal agreement to date with Terradot. The project will cover more than 200,000 hectares of rice fields in Rio Grande do Sul in southern Brazil. Its originality lies in a two-part promise: quickly reduce methane from flooded paddies, then permanently remove carbon dioxide with crushed volcanic rock. Google plans to buy the equivalent of one million metric tons of methane-related climate impact by 2030 and one million tons of permanent CO2 removal by 2040.
Two climate clocks in the same field
Methane and carbon dioxide operate on different time scales. Methane heats the atmosphere intensely in the near term but remains there for a shorter period. CO2 accumulates for centuries. Google and Terradot therefore want to address two clocks at once. Methane reduction should produce an immediate benefit, while enhanced rock weathering gradually gains strength and stores carbon for the long term.
This structure is more than a scientific argument. It is also a product innovation. Credits linked to methane reductions and credits representing CO2 removal will be generated and verified separately. The project therefore creates two climate assets on the same farm, each with its own schedule, measurement method and risk profile.
How a rice field becomes climate infrastructure
The first technique is Alternate Wetting and Drying. Instead of keeping rice paddies continuously flooded, farmers drain them periodically. This limits the activity of microorganisms that produce methane in oxygen-deprived soil. The practice can also reduce water use and some operating costs, provided it is adapted to local conditions and carefully managed.
The second technique involves spreading finely crushed basalt. As it dissolves under heat and water, the rock reacts with CO2 and accelerates a natural process known as mineral weathering. Carbon eventually ends up in stable chemical forms. Southern Brazil’s warm, wet climate, vast cultivated area and proximity to basalt quarries make the region particularly favorable. The project is described as the largest enhanced rock weathering deployment announced so far.
Google is buying a learning curve
The contract is not simply designed to offset future emissions. By reserving large volumes in advance, Google is financing industrialization. Terradot can organize rock logistics, compensate farmers, improve measurement protocols and spread fixed costs across an enormous area. In return, Google receives credits and, just as importantly, operational knowledge about a technology that remains young.
The mechanism resembles the power purchase agreements that once accelerated wind and solar energy. A large buyer promises demand over several years, giving a supplier enough visibility to invest. The difference is that the purchased product is not electricity recorded by a meter. It is a ton of climate impact that must be calculated, modeled and then verified. Data quality therefore becomes as important as the agricultural operation itself.
Price remains the decisive test
Google and Terradot have not disclosed the value of the agreement. Reuters notes, however, that a public 2024 contract for 90,000 tons of Terradot removals implied a price near $300 per ton. The threshold frequently cited for stimulating broader demand is around $100. Terradot chief executive James Kanoff says the new project remains above that target but represents a major step toward it.
Verification weighs heavily on the economics. According to Terradot, it can add more than $100 per ton to enhanced weathering costs. Allowing more carbon removal to accumulate before initiating independent verification could lower that unit expense. The strategy improves the business case, but it requires a balance between reducing costs and maintaining control. In a trust-based market, less frequent audits work only if the data between them remains robust and transparent.
Farmers sit at the center of the model
Success will not depend on Google and Terradot alone. It will rely on thousands of decisions made on farms: irrigation schedules, rock volumes, spreading quality, crop yields and emissions monitoring. Farmers must receive enough of the value created to accept changed practices and a higher level of traceability.
The model may provide direct gains. Alternate irrigation uses less water, while some minerals from basalt may improve soil health. Yet those benefits are neither automatic nor uniform. A protocol designed for one region must be adjusted to rice varieties, weather and water infrastructure. The project’s global promise will be credible only if replication preserves agronomic benefits and does not transfer risk to producers.
The growing shadow of data centers
The announcement comes as technology companies face growing scrutiny over their environmental footprint. Expanding data centers for artificial intelligence increases demand for electricity, equipment and sometimes water. Carbon removal purchases therefore cannot replace direct emissions cuts or clean energy procurement. They address the residual portion of a footprint that may itself continue to grow.
This is the central criticism of carbon credits: they can become permission to keep polluting. The Brazilian project will be judged not only on its certified tons, but also on the coherence of Google’s broader strategy. A high-quality credit makes sense when it complements genuine emissions reductions. It becomes far less persuasive when used to conceal uncontrolled consumption growth.
Exportable, but not a universal recipe
The partners believe the system could expand across Brazil’s 1.5 million hectares of rice cultivation and later reach other regions, including India and Vietnam. Terradot plans pilots in several countries before commercial scaling scheduled for 2028. The global ambition is logical: rice paddies produce a meaningful share of agricultural methane and are often located in climates favorable to rock weathering.
Replication will nevertheless face limits. The distance between quarries and farms determines the financial and carbon cost of transport. Rock composition affects reaction speed. Rainfall, water access and land ownership structures change the feasibility of alternate irrigation. Terradot’s real asset will not be a simple procedure, but its ability to adapt the technical combination to each territory while producing comparable data.
Climate becomes a value chain
Under this agreement, a rice field becomes a source of food, a methane reduction site, a carbon removal platform and an environmental database. Around it, a value chain brings together farmers, quarries, transporters, laboratories, certification bodies, financiers and technology buyers. That economic architecture, more than the headline volume alone, could make the project a precedent.
Google is purchasing two million tons of climate impact, but it is mainly financing an attempt to make this market measurable, cheaper and repeatable. The bet is powerful without being guaranteed. If the methods deliver, Rio Grande do Sul could provide a blueprint for global expansion. If monitoring costs remain too high or agricultural benefits disappoint, the experiment will expose the limits of a solution often presented as simple. Either way, Brazil’s rice fields are becoming a real-world test for the next climate economy.
