ON Hellisheiði geothermal power plant
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Climeworks utilizes DAC technology to extract CO₂ from the air, then stores it underground to mineralize and solidify.

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This project supports a form of direct air capture and storage - a carbon dioxide removal method that uses large fans to extract the CO₂ from air, before pumping it underground into special rock formations to be turned into stone.

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Negative Emissions

Direct air capture combined with storage is a form of carbon dioxide removal. Our partner Climeworks develops, builds and operates direct air capture machines that are powered solely by renewable energy or energy-from-waste.

Their CO₂ collectors selectively capture carbon dioxide in a two-step process. First, air is drawn into the collector with a fan, capturing carbon dioxide on the surface of a highly selective filter material that sits inside the collectors. After the filter material is full with carbon dioxide - the collector is closed and the temperature increased to between 80 and 100 °C releasing the CO₂. This high-purity, high-concentration carbon dioxide can be collected and stored, removing it from the atmosphere.

Life cycle analysis

There are many options around the world to store carbon dioxide after it has been captured from the air. Climeworks has joined forces with the Icelandic company Carbfix - one of the world experts in rapid underground mineralisation of carbon dioxide (which means turning carbon dioxide into stone). Iceland is one of several locations around the world that provide ideal conditions for this pioneering process. The setup for this project is located around the Hellisheiði geothermal power plant, which provides the renewable energy needed to run the Climeworks machines.

The carbon dioxide is removed from the air with Climeworks' direct air capture machines. Carbfix then mixes the carbon dioxide 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. This machine-based solution allows to exactly measure how much carbon dioxide has been removed and turned into stone.

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.


At Carbon Removed we love direct air capture as it is one of the most accurate and efficient (in terms of water and land area required) removal methods. Relatively small units can be placed at suitable locations (such as the geothermal power plant mentioned above) and continuously extract and store huge amounts of carbon dioxide.

Unfortunately a huge disadvantage of this project is the cost. As with all technologies in their infancy, direct air capture is currently one of the most expensive methods to remove CO₂ from the atmosphere but with enough support, we know this will change. We choose to fund this method as over time it will get cheaper and more cost effective.

This project is one of many we support - minimising the damage done to the environment and maximising the impact we can all have on climate change. It is important that everyone chooses to reduce their footprint and slow the emissions of dangerous greenhouse gases but combined with carbon removal projects such as this one, it is possible for us to fight and undo the climate crisis.

If you’re interested in supporting carbon removal projects like direct air capture, please start a subscription today and turn your emissions into trees and stone.