Underground Coal Gasification

Un-minable coal

Many coal seams are un-minable but could be partly set alight with a limited supply of oxygen and water pumped into the seam producing Syngas (CO and H2), plus methane. This can be used as fuel, or to produce liquid fuels.

C + H2O → CO  +  H2

A World Energy Council (2007) report estimated that 44 billion tonnes of coal in Australia could be suitable for underground coal gasification.
A trial in Queensland led to serious problems.

"gases released by Linc's activities at its underground coal gasification plant at Hopeland have caused the permanent acidification of the soil near the site.

Experts also found concentrations of hydrogen in the soil at explosive levels and abnormal amounts of methane, which they say is being artificially generated underground, over a wide area." ABC

Click on images for source and more information.

It would produce unacceptable amounts of CO2.

http://www.epmag.com/Production-Drilling/UCG-clean-energy-alternative_31029