The country’s CarbFix project, developed in collaboration with researchers and engineers from the utility company Reykjavik Energy, the University of Iceland, France’s National Centre for Scientific Research (CNRS) and Columbia University in the United States, makes it possible to petrify carbon released in large quantities by Iceland’s transport sector, industry and volcanoes.
Injecting CO2 into porous basalt rock and allowing it to turn into mineral over time is a technique which mimics a natural process that achieves the same result – only thousands of years later. “With this method we have actually changed the time scale dramatically,” said geologist Sandra Osk Snaebjornsdottir.
Research on the new carbon-storage method is currently being conducted at the Hellisheidi Geothermal Power Plant – one of the biggest in the world – sitting atop the Hengill volcano in south-western Iceland.
Much of the C02 generated by the plant is captured from the steam, liquefied into condensate, dissolved in large amounts of water, and transported in high-pressure pipes into basalt rock located 1,000 metres underground.
According to Snaebjornsdottir, almost all of the CO2 is turned into rock within approximately 2 years, once the gas comes into contact with the calcium, magnesium and iron present in the basalt. And once it solidifies – it stays solid, barring a volcanic eruption or similar natural event.
“If you have a volcanic eruption… and you heat up the rock to very high temperatures, then some of the mineral will break down and maybe dissolve in water,” said University of Iceland geochemist Sigurdur Gislason, adding that it’s nonetheless the safest and most stable method of storing carbon to date.
Although the process currently requires very large quantities of desalinated water – around 25 tonnes per tonne of CO2 – the research team is already working on a fix that could allow the method to function with saltwater, thereby making it useable around the world.
The CarbFix project was initiated partly as a means to achieve the country’s goal of slashing CO2 emissions by 40 per cent by 2030 under the Paris Agreement.