Calculating the difference in net emissions between using land to produce biofuel and the alternative: fuelling cars with gasoline and replanting forests on the land instead, revealed, that biofuel production was not a "green process" anyway.
Production of biofuel required tractors and fertilisers and land, all of which meant burning fossil fuels to make "green" fuel.
In the case of bioethanol produced from corn - an alternative to oil - "it's essentially a zero-sums game," said Ghislaine Kieffer, programme manager for Latin America at the International Energy Agency in Paris, France.
Environmentalists have also expressed concern over the growing political backing that biofuel is enjoying, which essentially means chopping down forests to make room for biofuel crops such as maize and sugarcane.
"When you do this, you immediately release between 100 and 200 tonnes of carbon [per hectare]," said Renton Righelato of the World Land Trust, UK, a conservation agency that seeks to preserve rainforests.
Righelato said findings further revealed that reforestation would sequester between two and nine times as much carbon over 30 years than would be saved by burning biofuels instead of gasoline.
"You get far more carbon sequestered by planting forests than you avoid emissions by producing biofuels on the same land," said Righelato.
He said, as such, governments should steer away from biofuel and focus on reforestation and maximising the efficiency of fossil fuels, if they are really concerned over controlling emissions.
"If the point of biofuels policies is to limit global warming, policy makers may be better advised in the short term to focus on increasing the efficiency of fossil fuel use, to conserve existing forests and savannahs, and to restore natural forest and grassland habitats on cropland that is not needed for food," Righelato said.
The study appears in the journal Science, reports New Scientist.