The Technology Review website reports that an American biotech-driven energy company, Luca Technologies, is investing US$ 76 million to scale up a process which utilizes coal-digesting microorganism to convert coal in underground beds to methane gas in industrial quantities. Methane is said to be a “greener fuel” because its burning releases only half the carbon dioxide emissions, relative to coal. The technology essentially harnesses the consortia of anaerobic microorganisms that naturally reside beneath the earth. By proper nutrient supplementation and “changing the chemistry of the microbes' living environment”, the microorganisms can be stimulated to produce large quantities of methane. In effect, the underground coal beds are converted in giant biogenic methane “geobioreactors”. The potential of the technology is said to be in the harnessing of buried hydrocarbon reserves “which cannot be extracted in an economical or environmentally benign fashion with current technologies and practices. These include deeply buried coal beds, organic-rich shales”..