Sizing up carbon capture and storage
Considered by some a silver bullet and by others a hopeless dream, the idea that we can simply capture our carbon dioxide emissions and store them safely away is nothing if not compelling. After all, it lends an air of practicality to the notion that human ingenuity can somehow continue the unabated use of fossil fuels over the coming decades without dangerously warming the climate.
This week’s Science (subscription) looks at how close we are to being able to capture carbon dioxide, both from the point of emission at coal- or gas-burning power plants, and directly from air. A series of news, opinion and review articles shows that while many obstacles need to be overcome before carbon capture and storage (CCS) is implemented effectively, there are also abundant reasons to hope that it will happen.
But the scale of the challenge is palpable. In a review, Stuart Hazeldine of the University of Edinburgh, UK, says that the construction of many tens to hundreds of large CCS plants worldwide would be needed to reduce future worldwide emissions from energy by 20%. And in order for the technology to make a substantial contribution to climate mitigation, a viable CCS industry needs to be in place between 2020 and 2030. Construction would have to start now if plants fitted with CCS technology are to be operational by 2014, giving enough time to demonstrate commercial credibility by 2020.
Last year, G8 leaders called for upwards of 20 demonstration CCS projects around the globe. A recent report from
the U.S. National Research Council reiterated this statement, calling for a suite of 15 to 20 power plants with CCS to be built before 2020. Today, a few such projects are in development, each of which is shown on a map accompanying the Science news feature. Most of these projects will take CO2 from natural gas reservoirs and bury it or pump into oil reservoirs to force more oil to the surface, thus making the whole process commercially viable. One such project is China’s first large-scale CCS effort, which is due to launch at a site on the plains of Inner Mongolia in the coming weeks.
But many more such plants are needed, and despite a recent boost in available money for CCS, Hazeldine notes that there is still a “lamentable lack of financial commitment to real construction”. His take home message? Technology isn’t the bottleneck in getting CCS off the ground. On the 10 year timescale, it’s legal permission, business development, and public opinion that could prevent CCS from being up and running by 2020.
Also featured in the Science special issue is a perspective by David Keith on the potential for direct capture of CO2 emissions from air, which Nicola Jones covered in a news feature for Nature (subscription) back in May. The special also has a number of perspectives on the technological aspects of CCS, from capturing CO2 to storing it onshore in geological formations or offshore in deep-sea sediments.
Olive Heffernan
Image credit: Carbon storage at Sleipner field, North Sea. Alligator film /BUG / StatoilHydro
