Climeworks

In the battle against climate change, few technologies are as ambitious — or as fiercely debated — as Direct Air Capture, the process of pulling CO₂ directly from the atmosphere. Climeworks, founded in Zurich in 2009 by Christoph Gebald and Jan Wurzbacher, two mechatronic engineers trained at ETH Zurich, has done more than any other company to transform this technology from an academic experiment into real industrial infrastructure. The mechanism Climeworks developed is elegant in its logic: high-efficiency filters adsorb CO₂ from ambient air. When saturated, the filters are heated, releasing concentrated gas that is then injected underground, where it mineralizes into basaltic rock within a few years, thanks to a partnership with Icelandic company Carbfix. This is not carbon offsetting or tree planting — it is permanent, verifiable, geolocated removal. Clieworks' most advanced project is called Mammoth, the world's largest commercial DAC plant, located in Iceland and powered entirely by geothermal energy. Designed to capture 36,000 tonnes of CO₂ per year at full capacity, the plant has faced significant technical challenges during its ramp-up phase: in 2024 it captured a total of 105 tonnes, with only 12 of its 72 planned collector units fully operational. These figures reflect the hurdles typical of first-of-a-kind industrial projects, but do not undermine the validity of the underlying chemical process. The financial response from the market has nonetheless been substantial. Climeworks has raised over one billion dollars in total funding, including a $650 million round in 2022 — the largest in the history of the carbon removal sector — and a further $162 million round in July 2025. Investors include Partners Group, Swiss Re, GIC, and Baillie Gifford. The current cost of removal stands at around $1,000 per tonne, but the co-CEOs aim to drive it down sharply through economies of scale: Gebald has stated that the company has already halved its internal cost to approximately $500 per tonne. On the commercial side, Climeworks has built a portfolio of corporate clients signing multi-year carbon removal contracts: Microsoft — the largest by volume, with agreements extended over time — alongside Stripe, Shopify, SAP, and Swiss Re. These long-term contracts serve a dual purpose: they guarantee future demand and act as leverage for financing new infrastructure. The path is not without obstacles. In 2025, in response to regulatory uncertainty and shifting macroeconomic conditions — particularly the rollback of US federal climate funding under the Trump administration — Climeworks announced a workforce reduction affecting more than 20% of its approximately 500 employees. The co-CEOs described it as a necessary «right-sizing» to ensure long-term sustainability. The climate and technological stakes could not be higher. The IPCC estimates that keeping global warming within 1.5°C will require removing between 100 and 1,000 billion tonnes of CO₂ by 2100. Direct Air Capture cannot do this alone, but for many experts it is an indispensable component of the solution portfolio. Climeworks bet on it when almost no one believed in it, and today — despite the operational challenges — it remains the global benchmark for a sector that could be worth hundreds of billions in the decades ahead.