The green tech that could help Iceland become carbon neutral by 2040

Inside a small, geodesic dome near Iceland’s Hellisheiði geothermal power station, water full of carbon dioxide is being pumped hundreds of metres down into the porous basalt. At least, I am assured it is: the water is so clear that the pipe looks empty when I peer through a viewing window at it. The CO2 will react with metals in the rock and turn into carbonates, locking it away safely for millennia.