Carbon removal through Enhanced Rock Weathering in the UK

Why this project?

This project addresses climate change by spreading crushed basalt rock on farmland across the UK to accelerate the natural process of CO₂ absorption. This process transforms CO₂ into stable mineral forms, locking it away for over 100,000 years. Enhanced Rock Weathering (ERW) has the potential to remove up to 4 billion tonnes of CO₂ annually – a staggering 40% of global climate targets. Using conventional farming equipment to distribute rocks, the project stands out for its efficiency and potential to boost agricultural crop productivity by up to 19%. In this way, it not only offers a sustainable pathway for long-term carbon sequestration but also demonstrates how current agricultural practices can be leveraged for environmental benefits.

Removing carbon naturally

Enhanced Rock Weathering (ERW) is a cutting-edge, nature-based carbon removal technology that speeds up the earth’s natural ability to capture and permanently store atmospheric CO₂. It mimics the process of geological weathering, where rainwater and air interact with rocks to trap CO₂ in stable minerals. This process has naturally removed CO₂ from the atmosphere for millions of years.

The concept is simple yet powerful. By spreading finely crushed basalt rock on farmland, the project increases the rock's surface area, speeding up this process from millions of years to just a few decades. The CO₂ combines with rainwater, forms a mild acid, and reacts with the rock to create solid carbonate minerals that store carbon safely and for over 100,000 years.

The scale of the project is already impressive. So far, UNDO has spread 399,210 tonnes of basalt over 27,000 hectares across the UK, removing at least 63,800 tonnes of CO₂. The approach integrates seamlessly with farming operations, creating a practical, scalable solution to climate change. ERW stands out for its dual benefits: capturing carbon for the long term and supporting sustainable agriculture. This innovation not only reduces emissions but also strengthens the agricultural sector, setting a new standard for climate action.

Enriching soils for farming

Enhanced rock weathering provides numerous benefits for farmers, communities, and the environment that extend far beyond carbon removal.

For farmers, applying crushed basalt enriches the soil, improves crop yields, and reduces the need for costly fertilizers. Basalt acts as a natural soil conditioner, gradually stabilizing soil pH through a slow-release process. This reduces the need for lime and helps prevent yield losses caused by soil acidity. Over time, the rock replenishes the soil with essential nutrients like potassium, calcium, and magnesium, addressing hidden crop deficiencies and making plants more resilient to stress. These improvements enhance soil fertility and ecosystem stability, fostering healthier growing conditions.

Farmers also benefit economically, as the process lowers input costs, results in better yields, and simplifies soil management. The project handles logistics, from sourcing and spreading the rock to providing detailed soil analyses, ensuring an easy and impactful adoption process. So far, 339 farms have been enriched with ERW practices.

The benefits extend to local communities as well. Quarry partners play a crucial role by supplying and hauling basalt, creating jobs, and supporting local economies. The project also promotes collaboration with academic institutions, regulatory bodies, and community stakeholders, ensuring transparency and shared progress.

Enhanced rock weathering thus helps farmers and communities thrive and demonstrates how local efforts can contribute to a global solution for climate change. In the upcoming years, the project will further scale up its efforts in the UK and start new activities in the United States and Canada.