Decarbonisation Technology May 2026 Issue

Africa’s Rift Valley: ideal location for DAC projects

A DAC project harnessing Kenya’s abundant geothermal energy sources significantly reduces operating costs while ensuring carbon-negative operations

A s a powerful greenhouse gas, carbon to reducing emissions, many countries are looking for ways to capture CO 2 efficiently. Direct air capture (DAC) offers an opportunity to lower atmospheric CO 2 levels, but concerns remain around process costs, particularly energy costs. A DAC project in Kenya is garnering high levels of interest because of its ability to harness an almost free and limitless supply of renewable energy – geothermal power. dioxide (CO 2 ) levels in the atmosphere are driving climate change. So, in addition Geothermal power in the Rift Valley Tectonic plate movements around 25 million years ago allowed water to percolate into contact with hot rocks 1-3 km beneath the surface, creating a mix of superheated, high- pressure water and steam – perfect conditions for generating geothermal energy. As a consequence, Kenya’s grid is now powered by nearly 90% renewable sources, with geothermal contributing 47%. However, this barely scratches the surface of the Rift Valley’s vast, untapped energy potential. This supply of clean, constant baseload power represents a significant opportunity to support a diverse ecosystem of green industries far beyond electricity generation. Crucially, this potential extends to the direct utilisation of geothermal heat – a valuable byproduct that is often wasted. For energy-intensive processes like DAC, this thermal energy is a game- changer. DAC machines can tap into residual heat to power sorbent regeneration, which is the critical process of releasing captured CO₂ from filters. This allows industries to decouple Khamis Mwalwati Muniru Octavia Carbon Antti Heikkilä and Samy Oumaziz Vaisala

their thermal needs from their electrical load, significantly lowering costs. When combined with the region’s ‘basalt synergy’ or the geological capacity to permanently mineralise captured CO₂ underground, this triad of renewable electricity, direct industrial heat, and secure storage potentially makes Kenya the world’s most competitive location for direct air carbon capture. Octavia Carbon As the Global South’s first DAC company, Octavia Carbon has commissioned the world’s second DAC and geological storage plant. Harnessing geothermal energy to capture CO 2 from the air for secure storage underground, it has developed a scalable process that offers significant potential for the future. After capturing CO 2 directly from ambient air, the company liquefies the gas and transfers it to a partner for permanent underground geological storage. Founded in 2022, Octavia Carbon now employs more than 60 people on its mission to reduce the costs of DAC technology while increasing its impact. The company’s goal is to provide an effective solution for durable carbon removal and to act as a catalyst for green industrial growth and climate justice in the Global South. In September 2025, the Second Africa Climate Summit concluded with a clear call to position Africa, not as a victim of climate change, but as a driver of solutions in the global climate economy. Octavia Carbon was established to become one of these solutions.