The Oil Drum

Underground coal gasification (UCG) is a technology that could be very useful for UK, given that UK has a lot of coal reserves that cannot be easily reached by conventional mining. CCS would be a necessary adjunct to such a technology, and UCG and CCS could have useful synergies.

More information can be found on www.ucgp.com. From the site:

“…..UCG in combination with CCS is recognised as a potential route to carbon abatement from coal. Reports suggest that UCG in combination with CO2 injection into adjacent coal seams to enhance coal bed methane (ECBM) is a potentially attractive option, particularly under river estuaries near-shore and eventually offshore coal.

UCG has synergies which may be important to CCS. First and foremost it is a gasification technology with all the benefits that accrue in terms of CO2 capture from pre-combustion gas. These include smaller more efficient separation plant, lower capture costs and the ability to produce hydrogen in bulk quantities. Furthermore, the composition of UCG clean gas, and the high pressure available, suggests that a range of CO2 capture options could be considered.

The scope for optimising the capture process is considerable and emissions already low for coal can be reduced by partial CO2 capture, to those of natural gas combined cycle (CCGT) or taken to a level approaching renewable energy. The process is particularly well suited to the production of low carbon gas mixtures of hydrogen and methane. These have higher energy densities and are safer to handle than pure hydrogen. Such mixtures may be suitable for existing gas transmission lines and could make an effective transport fuel for some vehicles…..”