The study, which set out to provide 'a comprehensive and objective, science-based analysis of the effects of biofuels on the environment', originates from a committee of the International Council for Science. Its findings conflict with certain aspects of EU legislation on biofuels, notably Europe's target for transport fuels to have a 10% share by 2020 and the EU's reluctance to recognise that growing biofuel crops can have indirect effects caused by changes in land use.
The study 'Rapid Assessment on Biofuels and the Environment' says current crops grown for biofuels are 'problematic', and others proposed for future biofuels, which are supposed to avoid harming food security or the environment, require land, water, nutrients, and other inputs, and therefore compete with food crops and lead to deforestation.
It casts doubt on the idea of using land that cannot be used for growing food, saying there is no evidence that non-food crops can be grown efficiently for energy production on land that could not also grow crops for food. And while it says opportunities for biofuel production exist that maximise social benefits while minimising environmental impacts, it says the extent of these win-win situations is limited and their contribution to society's energy budget will be very small.
T&E policy officer Nusa Urbancic said: 'This is 75 scientists from 21 countries expressing all the doubts about biofuels that environmental groups have been raising over the past few years. It reiterates the point that we should be encouraging good biofuels, not just any biofuels.'
The scientists look for benefits from biofuels and do highlight some. They say fuels made from organic waste are generally more benign environmentally than those from energy crops, low-input cultivation of perennial plants may provide cellulosic biomass with environmental benefits, and new liquid hydrocarbon fuels produced from cellulosic biomass currently being developed seem likely to offer several advantages over producing ethanol from cellulose.
But they warn that any guidelines for sustainable biofuel production cannot be based only on product life-cycle and farming standards 'as these cannot address the difficult issue of indirect land use resulting from growing demand'.
Another conclusion says the distribution of wealth is very uneven in many countries, and a high potential exists for the benefits of biofuels to fall largely to those with wealth.
And in a message relevant to the EU, the report says: 'In light of the potential adverse environmental consequences, potential displacement or competition with food crops, and difficulty of meeting these goals without large-scale land conversion, Current mandates and targets for liquid biofuels should be reconsidered'.