Many commentators believe that a continued global commitment to the use of coal to generate electricity at current or near current levels virtually ensures temperature increases of 2-3C above pre-industrial levels. In recent years, carbon capture and sequestration (CCS) has been touted as a technological “fix” that potentially would allow coal usage to continue virtually unabated, or at least would facilitate much less radical cuts than might otherwise be required. A new piece in the journal International Journal of Greenhouse Gas Control (subscription required) assesses the potential for geological storage of carbon dioxide in terrestrial and ocean saline aquifers, one of the three main options for geological storage of carbon dioxide, and the option that has the greatest storage capacity globally. The piece also discusses some of the threats that CCS may pose.
Among the take-aways from the article:
- Beyond the first commercial-scale project dedicated to disposing of carbon dioxide (the Sleipner natural gas project in the North Sea), there are a number of pilot operations that have been developed in recent years or are planned;
- While monitoring technologies for shallow groundwater, soil and the atmosphere have been developed for carbon dioxide storage, high natural fluctuations in these environments complicate detection of leaks from reservoirs. Technologies exist to detect and locate leaks at a site in Montana, but it could not quantify carbon dioxide leakage;
- An integral part of major industrialized States is to enable broad deployment of CCS by 2020.
There are a number of critiques of CCS that highlight some other substantial concerns about the viability of CCS, including potential costs, the speed at which the technology will be available on a commercial scale, and potential public resistance to the siting of pipelines and other critical infrastructure. However, some of the greatest concerns involve potential leakage of carbon dioxide, both as a potential health threat, and because even minimal leaks (approximately 1% annually) could obviate most of the benefits of CCS in terms of avoiding substantial temperature increases.