Turning CO2 to stone: world's largest carbon eating plant starts work in Iceland

The world's largest plant designed to suck carbon dioxide directly from the air and deposit it underground started operating on Wednesday, the company providing the technology said.

The Hellisheiði Geothermal Power Plant is the site of the original Carbfix project, which injected approximately 200 tons of CO2 into the subsurface and fixed it as stable carbonate minerals. © Wikimedia commons

Swiss start-up Climeworks AG, which specialises in capturing carbon dioxide directly from the air, has partnered with Icelandic carbon storage firm Carbfix ("we turn CO2 into stone") to develop a plant that sucks out up to 4,000 tons of CO2 per year.

That seems meagre: it's the equivalent of the annual emissions from about 790 cars. Last year, global CO2-emissions totalled 31.5 billion tonnes, according to the International Energy Agency. But it's a start. 

Direct air capture is one of the few technologies extracting carbon dioxide from the atmosphere and is viewed by scientists as vital to limit global warming, blamed for causing more heatwaves, wildfires, floods and rising sea levels. 

CO2 suction units created Climeworks and used in the plant in Iceland © Climeworks

Climeworks opened its first ever commercial carbon sucking plant in June 2017, a facility near Switzerland's capital Zürich, capable of dealing with 900 tons of CO2 (the equivalent of the output of some 200 cars) annually. The company then said that the plant was "a first step" in their goal to "capture 1 percent of the world's global CO2 emissions" with similar technology. To do so, there would need to be about 250,000 similar plants - but the new plant in Iceland is already four times bigger than the original installation. 

Deep underground

The Orca plant, a reference to the Icelandic word for energy, consists of eight large containers similar in looks to those used in the shipping industry, which employ high-tech filters and fans to extract carbon dioxide.

The isolated carbon is then mixed with water and pumped deep underground, where it slowly turns into rock. Both technologies are powered by renewable energy sourced from a nearby geothermal power plant.

Direct air capture is still a fledgling and costly technology, but developers hope to drive down prices by scaling up as more companies and consumers look to reduce their carbon footprint.

There are currently 15 direct air capture plants operating worldwide, capturing more than 9,000 tonnes of CO2 per year, according to the IEA. 

U.S. oil firm Occidental is parnering with Carbon Engineering to develop the largest direct-air-capture facility, to pull 1 million tonnes per year of carbon dioxide from the open air near some of its Texas oilfields.

Climeworks, which recently signed a 10-year carbon removal purchase agreement with major insurance firm Swiss Re, also offers a subscription service, which allows consumers to pay for carbon removal through monthly payments.

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(With Reuters)