https://www.ucg-gtl.com/what-is-ucg-gtl.html
UCG-GTL is the "revolutionary" successful combination of two known processes, Underground Coal Gasification (UCG) and the conversion of the resultant Gas To Liquids (GTL).
UGC: Underground Coal Gasification
Australia was leading the world's renewal of interest in the conversion of underground coal to an energy rich gas named SYNGAS. SYNGAS can be used as high quality feedstock for gas fired power stations and excitingly the production of HydroCarbon liquids as well as a range of other products.
The process has been labelled as "Underground Coal Gasification" where coal is heated creating a chemical process underground and the resultant gas (Syngas) is piped to the surface. Underground coal gasification (UCG) is an in-situ gasification process carried out in non-mined coal seams using injection and production wells drilled from the surface, which enables the coal to be converted into product gas.
There has not been much done in this area in Australia since I wrote this website in 2009