Here's an idea for dealing with carbon dioxide: Turn it into stone. Scientists in Iceland say they have managed the feat at the world's largest geothermal power plant, an accomplishment the Guardian says could have big implications for climate change. As they explain in Science, researchers with the CarbFix Project figured out how to capture CO2, then pump it into porous volcanic rocks deep in the Earth. There, the gas combined with minerals in the basaltic rocks and turned into limestone. Scientists actually sped up that natural process and were amazed at the results: 95% of the CO2 had turned to stone within two years, reports Wired. When this process occurs naturally, it can take hundreds of thousands of years. "It was a huge surprise to all the scientists involved in the project," lead author Juerg Matter tells the BBC.
By burying the emissions so deeply into such a stable form, the carbon dioxide is trapped in such a way that it cannot warm the planet, say the researchers. "In the future, we could think of using this for power plants in places where there’s a lot of basalt and there are many such places," says team member Martin Stute at Columbia University. Testing is already under way in the Columbia River Basalts in the Pacific Northwest, while India, home to many dirty coal plants, also boasts enormous basalt deposits in the Deccan Traps. Researchers are also hoping to find an even better reaction in a rock type found in Oman. The idea of burying CO2 under some kind of carbon capture and storage (CCS) method has been experimented with successfully for decades, but one major concern has revolved around the gas leaking back out. The Iceland method seems to solve that. (See what one company wants to turn carbon pellets into.)