Climeworks, a Swiss startup, opened its third plant in the world to remove carbon dioxide (CO2) from the air. Because we have been delaying zero emissions, it’s likely that the upcoming report from Intergovernmental Panel on Climate Change (IPCC) will emphasize the need for techniques to remove carbon dioxide from the atmosphere. Without ‘negative emissions’, it’s likely that that global average temperature would rise above the 2-degree Celsius goal set under the Paris climate agreement.
Trees can remove CO2 from the air, but we continue to release so much of it into the atmosphere, that we have to rely on other technologies also such as “direct air capture” (DAC). This technology involves using a fan to pass air over a surface containing a chemical agent that only reacts with carbon dioxide, then exposing the newly formed compound to heat. The energy breaks the bond, reversing the reaction and releasing the carbon dioxide, which can be stored or put to some use.
The Three Climework Plants
Climeworks has built and operated two such DAC plants for more than a year. In May 2017, it launched its first one, capable of capturing 900 metric tons annually, in Zurich Switzerland. The captured carbon dioxide was fed to a greenhouse, boosting the growth of the plants inside.
Last year, the company started operating the second, capturing 50 metric tons each year near a geothermal power plant in Hellisheidi, Iceland. The captured gas is injected underground along with water, where it reacts with rocks and turns into rock in less than two years.
The third plant is in Troia, Italty and will capture 150 metric tons of carbon dioxide, which will be converted to methane – a major component of natural gas – and will be used to power vehicles. The plant is funded largely through a research grant provided by the European Union.
The cost to capture one metric ton of carbon dioxide is $600 to $800, but the price should come down as the startup installs more of these units. Another startup, Carbon Engineering in Canada, claims to have already brought the cost down to $250 per metric ton of carbon dioxide.