For CO2 reduction, there's hope on the horizon
Putting CO2 away for good by turning it into stoneMartin Stute, Columbia University
Published Friday, June 10, 2016 SFGate
We seriously need to do something about CO2 emissions. Besides shifting to renewable energy sources and increasing energy efficiency, we need to start putting some of the CO2 away before it reaches the atmosphere. Perhaps the impacts of human-induced climate change will be so severe that we might even have to capture CO2 from the air and convert it into useful products such as plastic materials or put it someplace safe.
A group of scientists from several European countries and the United States including myself met in the middle, in Iceland, to figure out how CO2 could be put away safely – in the ground. In a recently published study, we demonstrated that two years after injecting CO2 underground at our pilot test site in Iceland, almost all of it has been converted into minerals.
Iceland is a very green country; almost all of its electricity comes from renewable sources including geothermal energy. Hot water from rocks beneath the surface is converted into steam which drives a turbine to generate electricity. However, geothermal power plants there do emit CO2 (much less than a comparable coal-fired power plant) because the hot steam from deep wells that runs the turbines also contains CO2 and sometimes hydrogen sulfide (H2S). Those gases usually just get released into the air.
Is there another place we could put these gases?