Coal clarification

From Harry Bradbury, Dermot Roddy and Paul Younger,  Five-Quarter Fred Pearce’s article on underground coal gasification  (15 February, p 36) misrepresents both the science and the words  of explanation given by three of the directors of UK energy firm Five-Quarter on its method of obtaining unconventional gas from rocks. Five-Quarter’s process – called “deep gas winning” – involves different chemical processes from the endless references to “burning coal” – namely partial-oxidation and pyrolysis, gasifying both coal and the kerogen in the surrounding rock within a carefully-created finite chamber, with all gases captured and none released to the atmosphere. Pearce quotes Bradbury on  the subject of underground coal, saying: “We want to burn it where it sits to revive industry.” We did not use and would never use the term “burn”. Burning coal would be a wasteful, dangerous and pointless use of this complex and valuable energy source, as was clearly pointed out. Newcastle upon Tyne, UK