This hidden Icelandic carbon plant could help win the war on climate change

The world's biggest carbon capture facility has opened in Iceland.

Save 50% when you subscribe to BBC Science Focus Magazine!

Published: June 7, 2024 at 3:00 pm

Could literally pulling CO₂ from the atmosphere be one of our best weapons against climate change? Absolutely, according to Swiss company Climeworks, who have just unveiled the world’s largest direct carbon capture and storage plant.

The new plant, known as Mammoth, is based in Hellisheiði, Iceland and is nine times bigger than Orca, Climeworks’ first plant. Mammoth aims to remove 36,000 metric tons of carbon from the air each year –  roughly the same as taking 8,600 cars off the road.

Running on renewable energy, Mammoth works by capturing the carbon dioxide from the air, and then moving the gas to a facility where it’s mixed with water and pumped deep underground.

Over time this carbonated water reacts with the natural porous basalt rocks, turning into solid carbonate minerals which solidify underground within the upper mantle. The rocks remain here for thousands of years, meaning that carbon is safely removed from the atmosphere.

With 12 of its eventual 72 collector containers installed, the Mammoth plant aims to be at full capacity by the end of 2024.

People watching crane lifting building materials.
Kári Helgason, head of research and development at Carbfix and Lukas Kaufmann, project manager at Climeworks supervise the very early stages of construction at the Mammoth plant. Here, the injection well for the Carbfix storage plant is being drilled down to a depth of between 350 and 712m. Photo by Climeworks

Christoph Gebald and Jan Wurzbacher, two Swiss mechanical engineers and the founders of Climeworks, first demonstrated their ideas for a direct air capture plant in 2015. Since then their company has grown rapidly. These two operational facilities are just the start of what they hope will be a game-changer in removing carbon from the atmosphere.

Aerial view of building site.
The foundations of the maintenance floor being laid for the Mammoth plant in Hellisheiði, Iceland, in December 2022. Photo by Climeworks

They will have their work cut out. Currently, CO2 concentration in the atmosphere is approximately 427 parts per million, according to the Keeling curve – a daily measurement taken at the Scripps Institution of Oceanography at UC San Diego. This compares to pre-industrial levels of CO2 well under 300 parts per million.

Snow-covered industrial complex
An aerial view of the Mammoth Climeworks carbon capture plant as it nears operational status, December 2023. Photo by Climeworks
A dome in a snowly landscape.
Carbfix's CO2 injection site is located next to the Mammoth plant in Hellisheiði, Iceland. Here the carbon extracted from the air is mixed with water and injected into a storage formation, at a depth of between 350 and 712m underground. The Carbfix storage technology does not involve injecting gaseous CO2 into the bedrock and thus does not require a sealed caprock to ensure containment. Photo by Carbfix/Climeworks
People in industrial corridor.
Workers at the Mammoth plant monitor progress shortly after operations start, May 2024. Photo by Climeworks
Person standing under huge outdoor fans.
A worker standing next to an almost complete CO2 collector container tower in December 2023. Photo by Climeworks
undefined
Huge fans on industrial building.
CO2 collector containers on the front of the Mammoth carbon capture plant, with two banks of 12 ventilators that release air back into the atmosphere once carbon has been extracted. Photo by Climeworks
Birds-eye view of industrial buildings covered in snow.
An aerial view of the Mammoth carbon capture plant in December 2023. Photo by Climeworks
Two people in high visibility jackets walking.
Jan Wurzbacher and Christoph Gebald inside Climeworks' Mammoth plant as operations commence in May 2024. Photo by Climeworks
Aerial view of industrial fans and black volcanic soil.
An aerial view of collector containers at the Climeworks Mammoth plant in Hellisheiði, Iceland, May 2024. Photo by Climeworks

Climeworks has already started work on its third-generation direct air capture technology, which will have an even larger capacity. This larger facility will first be constructed in the USA. If it proves successful, more sites around the world will play host to new carbon capture plants.

Industrial fans outside.
Collector containers at the Climeworks Mammoth plant in Hellisheiði, Iceland, May 2024. Photo by Climeworks

The company hopes that by building more facilities such as Orca and Mammoth, they will be able to reach megaton carbon removal capacity by 2030 and gigaton scale by 2050.

Whether this will help to reduce the amount of carbon in the atmosphere remains to be seen. But whatever happens to our planet over the coming decades, technology will have a big role to play.

Aerial view of huge white industrial buildings.
Rendering of a Climeworks third-generation carbon-capture plant, planned for construction in the USA. Photo by Climeworks

Read more: