Direct air capture to help reverse climate change

How is carbon dioxide removed from the atmosphere? One of the key ways to stop global warming is through direct air capture technology

Climeworks develops, builds and operates direct air capture machines

With our technology, we capture carbon dioxide directly from the air; removing unavoidable and historic CO₂ emissions. The air-captured carbon dioxide can either be recycled and used as a raw material, or completely removed from the air by safely storing it. Direct air capture, therefore, is one of the key ways to stop global warming by reducing the amount of potentially harmful CO₂ in the Earth’s atmosphere.

Our machines consist of modular CO₂ collectors that can be stacked to build machines of any size. Climeworks' direct air capture machines are powered solely by renewable energy or energy-from-waste. An independent life cycle assessment has shown that the grey emissions of our machines are below 10%, which means that out of 100 tons of carbon dioxide that are captured from the air, at least 90 tons are permanently removed and only up to 10 tons are re-emitted.

The fans of Climeworks' Orca plant

How does direct air capture remove carbon dioxide from the atmosphere?

Our CO₂ collectors selectively capture carbon dioxide in a two-step process. First, air is drawn into the collector with a fan. Carbon dioxide is captured on the surface of a highly selective filter material that sits inside the collectors. Second, after the filter material is full with carbon dioxide, the collector is closed and we increase the temperature to between 80 and 100 °C - this releases the carbon dioxide. Finally, we can collect this high-purity, high-concentration carbon dioxide.

Leading scientific studies indicate that by mid-century 10 billion tons of carbon dioxide will need to be removed from the air every year (source). Direct air capture is one solution that can help achieve this goal. In order to scale direct air capture up to the levels required, we need to start today and #actnow.

Video thumbnail

See all the Climeworks plants in the roadmap.

Direct air capture and storage: a way to stop global warming

From air to earth, removing harmful amounts of carbon dioxide

Direct air capture is a form of carbon dioxide removal if it is combined with storage. Carbon dioxide removal is a term used to describe approaches that remove carbon dioxide from the air permanently. This means that historic emissions are physically removed from the air. There are many options around the world to store carbon dioxide after it has been captured from the air. We focus on natural sinks, such as the underground mineralization of carbon dioxide.

Other approaches for carbon removal include afforestation and reforestation (trees capture carbon dioxide when they grow), bioenergy combined with carbon capture and storage (short: BECCS), or enhanced weathering. The global capacity to store carbon dioxide is vast and lies between 5 and 30 trillion tons (source). What makes direct air capture a unique approach is that it has the smallest land and water usage of all carbon dioxide removal approaches.

Our collaboration with Carbfix ensures that air-captured CO₂ is permanently removed from the Earth's atmosphere and a healthy balance is restored

For our flagship facility Orca, the world's largest direct air capture and storage plant, we have joined forces with the Icelandic company Carbfix. Carbfix has a strong scientific backbone and is one of the world's experts in rapid underground mineralization of carbon dioxide.

Located near the Hellisheiði geothermal power plant, which provides the renewable energy we need to run the Climeworks machines, Orca removes 4'000 tons of carbon dioxide per year. Carbfix mixes the carbon dioxide that Orca captures with water and pumps it deep underground. Through natural mineralization, the carbon dioxide reacts with the basalt rock and turns into stone within a few years.

The carbon dioxide is thus removed from the air and returned to earth, permanently and safely. With our machine-based solution, we can exactly measure how much carbon dioxide has been removed and turned into stone. Even though Iceland provides ideal conditions for direct air capture and storage, this process can also be applied in other areas around the world where renewable energy and geological storage options are available.

Climeworks direct air capture technology combined with the storage process developed by Icelandic company Carbfix removes carbon dioxide from the air and stores it permanently underground.

Direct air capture also means CO₂ can be used as a raw material in many useful applications

Maintaining a healthy balance

Direct air capture also provides a sustainable source of carbon dioxide. We capture the carbon dioxide in its pure form, meaning it can be re-used for several applications. In other words: the gas is recycled from air as a useful raw material. Thereby we maintain a healthy balance of carbon dioxide in the air because no additional carbon dioxide is produced.

The pure carbon dioxide can be used to produce renewable, carbon-neutral fuels and materials. Climeworks is involved in several projects and partnerships within this field, such as:

Learn about our solutions