The conversion of coal into liquid fuel could prove to be one of the cleanest and most environmentally friendly ways to power jets, trucks and trains, according to a Commentary published online this week in Nature Geoscience.

Reducing carbon emissions to a level that will prevent the worst consequences of climate change will not be easy. Daniel Schrag suggests that an old technology used for converting coal into liquid fuel ― known as the Fischer-Tropsch process ― could be made to produce diesel and jet fuel with a low carbon footprint. The carbon dioxide emitted during this process is removed, because it is toxic to the catalysts that convert coal into fuel. If this waste carbon dioxide is stored in geological repositories, carbon emissions arising from the production and use of coal-derived fuels will be lower than those from petroleum.

The author suggests that the substitution of some of the coal with biomass could reduce carbon dioxide emissions further.