Research Highlights

Nature Reports Climate Change
Published online: 10 July 2008 | doi:10.1038/climate.2008.70

Fuelling the future

Olive Heffernan

Env. Sci. Tech. doi:10.1021/es800052w (2008)

GGPHOTOWORLD, ISTOCKPHOTO

Biofuels could be part of a sustainable energy solution if grown on abandoned agricultural lands, suggests a new study. Once hailed as a magic bullet for producing clean energy, biofuels, such as ethanol made from corn, have recently had their green credentials attacked by critics who say the production of plant-based fuels can contribute to world food shortages and to climate change.

Combining historical and satellite data with ecosystem modelling, Elliott Campbell of the Carnegie Institution of Washington and colleagues estimated that over a billion acres of once productive land now lies fallow throughout the world. Their new global inventory of abandoned agricultural lands equates to 66–110 per cent of previous estimates and about one-quarter of the global land area currently in use for growing crops.

Though this land has been discarded by conventional food crop producers, it could still be suitable for low-input crops such as switchgrass. Planting all of the available area with biofuel crops would meet up to eight per cent of current energy needs in countries such as the United States, say the authors, meeting a small but meaningful fraction of the global energy demand.