Carbon capture and storage (CCS), a technique that captures carbon emissions from industrial and coal-fired plants and buries them underground, is understandably controversial. Researchers have in the past shown that the ultra-expensive technique could leak carbon into groundwater aquifers, making the water undrinkable. And there is the ever-present problem of what happens if all the pressurized carbon stored underground is disturbed and, say, gets released back into the air. But now scientists at the Lawrence Berkeley National Laboratory claim that large-scale underground storage is safer than previously thought.
According to researchers, underground pressure from injected CO2 won't be a problem at most storage sites. ScienceDaily explains:
Dr. Zhou and fellow researcher Dr. Jens Birkholzer considered three different types of storage reservoirs: closed, partially closed and open. They indicate that the storage of carbon dioxide deep underground will occur mainly in partially closed or open formations, where pressure build-up is relieved naturally by movement of native saline waters into regions far away from where carbon dioxide injection occurs.
This can partially ensure that pressure build-up is relieved—but the researchers admit that other pressure management strategies will also be needed. In any case, pressure management probably won't be an issue for a long time to come, at least in the U.S. The $1.3 billion FutureGen CCS project has been in the works for years, and has already been scaled down from a new CCS-equipped power plant to a smaller retrofitted one in Illinois. CCS, in other words, isn't even close to becoming a large-scale solution for anything.