(First published 17/12/2017)
As we try to slow our carbon emissions, we also need to get carbon out of the air. A new industry is springing up to meet the challenge, but can it scale fast enough?
If humans stopped emitting greenhouse gases tomorrow, we’d still have a problem: Since the industrial revolution, fossil fuels and industry have already emitted more than 1.5 trillion tons of carbon dioxide; another 600 billion tons have come from changing land use. In April, the concentration of CO2 in the air went over 410 parts per million. The last time the concentration was this high–likely during the Pliocene era, when mastodons roamed North America–humans didn’t exist.
As the heat-trapping gases in the atmosphere have grown, so has the global temperature, triggering droughts, wildfires, flooding, and other extreme weather. To have any chance of avoiding catastrophic climate change, some climate researchers say, we’ll need to continue shifting to solar power and electric cars–but we’ll also likely need to use technology to begin sucking large quantities of carbon dioxide directly from the air. Trees alone probably can’t do the job. It poses a question: Can the fledgling “direct air capture” industry scale up quickly enough?
The first commercial plant to pull carbon dioxide from the air opened in Switzerland in May 2017, collecting CO2 that it currently sells to a nearby greenhouse to help plants grow faster. The same startup, Climeworks, opened a second plant in Iceland in October, injecting the CO2 underground, where it can be permanently stored in rocks. Global Thermostat, based in New York, is currently building its first commercial units, which will begin pulling carbon dioxide from the air in 2018. In December, Canada-based Carbon Engineering demonstrated that it could use CO2 pulled from the air to make carbon-neutral fuel; the company is currently raising funds for a larger demonstration plant that it will test for a few years before it begins selling or licensing its technology.
[Photo: Carbon Engineering]