Biofuels will cause more harm than good to the environment unless strict controls are imposed on how they are grown, according to the Royal Society.

The fuels have the potential to help to reduce the greenhouse gas emissions driving climate change, yet habitats could be devastated, scientists said after a 15-month inquiry.

The EU is reexamining its targets for biofuels. Stavros Dimas, the Environment Commissioner, has admitted that the adverse effects on the environment and poor communities have been underestimated. Concerns are rising over forests being cut down and habitats such as savannah dug up to make room for biofuel crops. People in the areas affected may have little say in the decisions, and there is competition for land between biofuels and the need to grow food for a growing population.

Biofuels, derived from plant crops such as maize and rapeseed oil, are added to conventional fuels. The Royal Society report urges the Government to switch emphasis from the quantity of biofuels produced to the effect on greenhouse gas emissions. Professor John Pickett, of Rothamsted Research, who chaired the inquiry, said that not enough was known about the benefits and costs of each biofuel crop.

From April, the Government’s renewable transport fuels obligation will require suppliers to ensure that 5 per cent of fuel sold here comes from renewable sources. The report said that it must take account of effectiveness in reducing greenhouse gas emissions.

The entire supply chain must be assessed, from the fertilisers used to grow the biofuels to the fossil fuel they replace, Professor Pickett said. “One biofuel is not the same as another. The greenhouse gas savings of each depends on how crops are grown and converted and how the fuel is used. Indiscriminately increasing the amount we are using may not automatically lead to the best reductions in emissions.”

The Department for Transport said that within two years the impact of each biofuel on tackling climate change would be taken into account.

The green gallon

— Biofuels are just the latest form of organic material to be used for fuel
— Bioethanol and biodiesel are derived from crops. In the US, maize is the prime source; here, rapeseed oil is often used
— Forests store carbon dioxide, as do soils that contain organic matter, so when the lumberjacks and ploughmen move in there are big greenhouse gas emissions
— Wheat prices have been pushed up by the use of land for biofuels
— Rising prices of fossil fuels, and concerns over supply, make biofuels an attractive alternative

Times recommends

• Energy-saving ideas from switched-on professor
• Rooks are as clever with tools as chimpanzees
• Burping of the lambs blows roast off menu