Why U.S.-Chinese Cooperation on CO2 Capture and Storage Makes Sense
By Eric Larson
The U.S. House of Representatives passed climate legislation last year that called for an 83 percent reduction in greenhouse gas emissions by 2050. Scientists agree that industrialized countries as a whole need to reduce emissions by about this much in order to limit warming of the earth to within a “safe” level. One way such a large reduction could be achieved is by phasing out fossil fuel use to zero by 2050. The daunting nature of this task is a key reason why scientists and engineers are working hard to find ways to enable continued burning of some fossil fuels while still reducing emissions.
One approach is to capture the carbon dioxide (CO2) from fossil fuel combustion and bury it permanently deep underground. If CO2 capture and storage (CCS) technology works, it will buy valuable time for the transition to a non-fossil fuel world.
Commercial-scale demonstrations of CCS are now ongoing in a few places worldwide, including one project that has been in operation since 1996. Encouragingly, none of the projects have shown any leakage of CO2, but many more such facilities are needed to provide confidence that CCS can work in a wide range of underground geologies. Leaders of the Group of Eight industrialized nations have called for 20 large-scale CCS projects to be deployed during the next decade, and the U.S. intends to launch five to ten such projects by 2016.
A research paper I co-authored with Chinese and American colleagues, which was recently published online by the journal Energy and Environmental Science, suggests that there would be mutual benefits for the U.S. to cosponsor large-scale CCS demonstration projects in China.
Why China? For two reasons. First, China is the world’s largest emitter of CO2, due largely to its high dependence on carbon-intensive coal. Coal meets about 70 percent of China’s energy demands, and coal use is currently growing at nearly ten percent per year, corresponding to a doubling in use every seven years. In 2009, China used more than three times as much coal as the U.S. did.
Second, China is unique in the world in having a large industry converting coal into chemicals like ammonia and methanol. There are hundreds of these facilities, as identified by pins on the map below. What makes such facilities of special interest for CCS is that they produce a nearly pure stream of CO2 as an intrinsic byproduct, so that capturing it for underground storage is relatively inexpensive.
Map showing potential for CCS demonstration projects in China. Coal-to-chemicals/fuels facilities are marked by pins. Large pins indicate coal-to-chemicals/fuels facilities located near prospective CO2 underground storage sites. Credit: Climate Central/Remik Ziemlinski
Why U.S.-China collaboration on CCS in China? The U.S. is a close second to China in CO2 emissions, with more than 400 coal power plants accounting for nearly half of our electricity. CCS is thus a key technology if the U.S. hopes to continue relying on coal power in a carbon-constrained world. But the pace of CCS development in the U.S. is lethargic in large part because the costs of carrying out large-scale CCS demonstration projects there is high: it is costly to capture and concentrate the CO2 from coal-fired power plants in order to inject it underground. This is in contrast to capturing CO2 from coal-to-chemicals plants, but there are less than a handful of these in the U.S.
With its roughly 400 coal-to-chemicals facilities, China has much more “cheap” CO2 that can be used in CO2 demonstration projects. By sharing the costs and the learning from such projects, America and China could each spend less money developing CCS technology while also speeding up the date by which each of them will be able to deploy it commercially.
Our paper identifies 27 large coal-to-chemicals/fuels facilities in China (big pins on the map) that are also near prospective underground CO2 storage sites (light green shading on the map). We estimate costs for CCS projects that might involve these facilities and conclude that the costs are modest, leading to our suggestion that there would be mutual value for the U.S. (and other countries) to help support CCS demonstration projects in China.