The European and global potential of carbon dioxide sequestration in tackling climate change

Although, it has received relatively little attention as a potential method of combating climate change in comparison to energy reduction measures and development of carbon-free energy technologies, sequestration of carbon dioxide in geologic or biospheric sinks has enormous potential. This paper reviews the potential for sequestration using geological and ocean storage as a means of reducing carbon dioxide emissions. Considerable quantities of carbon dioxide separated from natural gas deposits and from hydrogen production from steam reforming of methane are already used in enhanced oil recovery and in extraction of coalbed methane, the carbon dioxide remaining sequestered at the end of the process. A number of barriers lie in the way of its implementation on a large scale. There are concerns about possible environmental effects of large-scale injection of carbon dioxide especially into the oceans. Available technologies, especially of separating and capturing the carbon dioxide from waste stream, have high costs at present, perhaps representing an additional 40-100% onto the costs of generating electricity. In most of the world there are no mechanisms to encourage firms to consider sequestration. Considerable R&D is required to bring down the costs of the process, to elucidate the environmental effects of storage and to ensure that carbon dioxide will not escape from stores in unacceptably short timescales. However, the potential of sequestration should not be underestimated as a contribution to global climate change mitigation measures.