'Fantasy' technology pulls carbon dioxide out of air, stores it
NEW YORK — On a field ringed by rolling green hills in Iceland, fans attached to metal structures that look like an industrial-sized Lego project are spinning. Their mission is to scrub the atmosphere by sucking carbon dioxide from the air and storing it safely underground.
Just a few years ago, this technology, known as “direct air capture,” was seen by many as a fantasy. But the technology has evolved to where people consider it a serious tool in fighting climate change.
The Iceland plant, called Orca, is the largest such facility in the world, capturing about 4,000 metric tons of carbon dioxide per year. Experts say 10 billion tons of carbon dioxide must be removed annually by mid-century.
“Effectively, in 30 years’ time, we need a worldwide enterprise that is twice as big as the oil and gas industry, and that works in reverse,” said Julio Friedmann, senior research scholar at the Center on Global Energy Policy at Columbia University.
Leading scientific agencies including the United Nations Intergovernmental Panel on Climate Change say that even if the world manages to stop producing harmful emissions, that still won’t be enough to avert a climate catastrophe. They say we need to suck massive amounts of carbon dioxide out of the air and put it back underground — yielding what some call “negative emissions.”
“We have already failed on climate to the extent to which direct air capture is one of the many things we must do,” Friedmann said. “We have already emitted so many greenhouse gases at such an incredible volume and rate that CO2 removal at enormous scales is required, as well as reduction of emissions.”
As dire warnings have accelerated, technology to vacuum carbon dioxide from the air has advanced. Currently, a handful of companies operate such plants on a commercial scale, including Climeworks, which built the Orca plant in Iceland, and Carbon Engineering, which built a different type of direct air capture plant in British Columbia. And now that the technology has been proven, both companies have ambitions for major expansion.
Direct capture at work
At Climeworks’ Orca plant near Reykjavik, fans suck air into big, black collection boxes where the carbon dioxide accumulates on a filter. Then it’s heated with geothermal energy, combined with water and pumped deep underground into basalt rock formations. Within a few years, Climeworks says, the carbon dioxide turns into stone.
It takes energy to build and run Climeworks’ plants. Throughout the life cycle of the Orca plant, including construction, 10 tons of carbon dioxide are emitted for every 100 tons of carbon dioxide removed from the air. Carbon Engineering’s plants can run on renewable energy or natural gas, and when natural gas is used, the carbon dioxide generated during combustion is captured.
Carbon dioxide can also be injected into geological reservoirs such as depleted oil and gas fields. Carbon Engineering is taking that approach in partnership with Occidental Petroleum to build what’s expected to be the world’s largest direct air capture facility in the Southwest’s Permian Basin — the most productive U.S. oil field.
Direct air capture plants globally are removing about 9,000 tons of carbon dioxide from the air annually, according to the International Energy Agency.
Climeworks built its first direct air capture plant in 2017 in Hinwil, Switzerland, which captured 900 metric tons of carbon dioxide annually that was sold to companies for use in fizzy beverages and fertilizer. The company built another plant, called Artic Fox, in Iceland that same year; it captured up to 50 metric tons of carbon dioxide annually that was injected underground.
Big plans, challenges
Their plans call for scaling up to remove several million metric tons of carbon dioxide annually by 2030. Daniel Eggers, chief commercial officer at Climeworks, said that would mean increasing capacity by a factor of 10 almost every three years.
Estimates vary, but it currently costs about $500 to $600 per ton to remove carbon dioxide using direct air capture, said Colin McCormick, chief innovation officer at Carbon Direct, which invests in carbon removal projects and advises businesses on buying such services.
Within the next decade, experts say, the cost of direct air capture could fall to $200 per ton or less.
For years, companies bought carbon offsets by doing things like investing in reforestation projects. But recent studies have shown many offsets don’t deliver the promised environmental benefits.
The Department of Energy announced Friday a goal to reduce the cost of carbon removal and storage to $100 per metric ton, saying it would collaborate with communities, industry and academia to spur technological innovation.
Oil companies such as Occidental and Exxon have been practicing a different form of carbon capture for decades. For the most part, they are taking carbon dioxide emissions from production facilities and injecting it underground to shake loose more oil and gas from between rocks.
Some question the environmental benefits of using captured CO2 to produce more fossil fuels that are eventually burned, producing greenhouse gases.
