Iceland is geologically active, with hot rocks and steam just below the surface in many places.
A web of pipelines and silver geodesic domes in the southwestern part of the island
piggyback on these geothermal features
to create power and also to turn atmospheric carbon dioxide into rock.
Waste heat from a geothermal power plant powers filters that pull carbon dioxide out of the air.
Pipes carry CO2 and water to a geodesic dome where the mixture is
injected more than 700 meters underground.
In as little as a few months,
the basalt bedrock reacts with the injected gas and forms veins of
carbonate minerals in the rock.
The project puts away just 50 tons of carbon
each year, so it's not a cure-all for reaching negative emissions yet,
but it proves that air capture and underground storage of carbon dioxide can work.
To learn more about this technology and others,
read "Scrubbing Carbon from the Sky" by Richard Conniff
at sciam.com/lastresort.
For Scientific American, I'm Liz Tormes.