Prospects for underground coal gasification in carbon-constrained world

Underground coal gasification (UCG) has re-emerged as an energy technology for coal conversion and utilization given its attractive economics, ability to access inaccessible coals, and versatility of use. Based on published and new cost estimates, engineering analyses, and new commercial pilots it appears that UCG can produce syngas for 1/2 to 1/4 of the cost compared to surface gasifiers. New pilots announced in India, Canada, New Zealand, Wyoming, Alberta, China, and Australia to commence in 2009-2010 are preludes to commercial projects to produce hydrogen, power, liquid fuels, and chemicals. Importantly, UCG may have special promise in combination with carbon capture and sequestration (CCS). First, there is a high degree of coincidence between coal resources and potential sequestration sites. Second, preliminary engineering and economic assessments suggest that it would be possible to fully or partially decarbonize many UCG product streams with CCS at costs at or below their surface equivalents without CCS. At present, all projects proposed for North America have CCS as a component to their carbon management strategy. (C) 2009 Elsevier Ltd. All rights reserved.