London, Feb 8: Biofuels are one of the biggest revolutions in the energy sector , but little known is the fact that they are worsening the menace of global warming instead of curbing it. According to studies publised in the journal Science, growing crops to make biofuels results in vast amounts of carbon dioxide being released into the atmosphere and does nothing to stop global warming.

The biofuels actually make global warming worse by adding to the man-made emissions of carbon dioxide that they are supposed to curb, the studies claim. ''This research examines the conversion of land for biofuels and asks the question 'is it worth it?' Does the carbon you lose by converting forests, grasslands and peat lands outweigh the carbon you 'save' by using biofuels instead of fossil fuels?'' said Joe Fargioine of the US Nature Conservancy who was the lead scientist in one of the studies.

''And surprisingly the answer is 'no'. These natural areas store a lot of carbon, so converting them to croplands results in tonnes of carbon emitted into the atmosphere,'' he said.

The scientists carried out an analysis that has been missing in the rush to grow biofuels, encouraged by policies in the U S and Europe where proponents have been keen to extol biofuels' virtues as a green alternative to the fossil fuels used for transport.

Surprisingly, the studies show that a range of biofuel crops now being grown to produce ''green'' alternatives to oil-based fossil fuels release far more carbon dioxide into the air than can be absorbed by the growing plants, the Independent reported.

The scientists found that, in the case of some crops, it would take several centuries of growing them to pay off the ''carbon debt'' caused by their initial cultivation. Those environmental costs do not take into account any extra destruction to the environment.

UNI