14/01/2008 (BBC News) - Biofuels may play a role in curbing climate change, says Britain's Royal Society, but may create environmental problems unless implemented with care.

In a new report, the Society suggests current EU and UK policies are not guaranteed to reduce emissions.

It advocates more research into all aspects of biofuel production and use.

The report says the British government should use financial incentives to ensure companies adopt cutting-edge and carbon-efficient technologies.

"Biofuels could play an important role in cutting greenhouse gas emissions from transport, both in Britain and globally," said Professor John Pickett from Rothamsted Research, who chaired the Royal Society's study.

"But it would be disastrous if biofuel production made further inroads into biological diversity and natural ecosystems.

"We must not create new environmental or social problems in our efforts to deal with climate change."

Variable savings

Biofuels - principally ethanol and diesel made from plants - are one of the few viable options for replacing the liquid fuels derived from petroleum that are used in transport, the source of about one quarter of the human race's greenhouse gas emissions.

Vehicles, and the infrastructure for delivering fuel through filling stations, can be modified at marginal cost - certainly compared with the price of a large-scale switch to hydrogen or electric vehicles, even if they were to prove technologically and economically worthwhile.

Hence the adoption by Europe and the US of policies to stimulate biofuel production and use.

But a number of recent scientific studies have shown that the carbon savings from using biofuels compared with petrol and diesel vary hugely, depending on what crop is grown and where, how it is harvested and processed, and other factors.

There are also concerns that widespread planting and use of biofuel crops would threaten natural ecosystems and raise food prices.

Policymakers are increasingly aware of such concerns. Before the Royal Society launched its report, European Environment Commissioner Stavros Dimas told the BBC that the EU had not foreseen all the issues thrown up by its target of providing 10% of Europe's transport fuel from plants.

Launching the Royal Society report, Professor Pickett noted that current EU and US policies did not mandate that biofuels should achieve any carbon saving.

The report said that the UK government's Renewable Transport Fuel Obligation (RTFO), which mandates that 5% of fuel sold on filling station forecourts by 2010 must come from renewable sources, suffers from the same flaw, though changes are being discussed in Whitehall.

As a result, the report concludes, these policies "will do more for economic development and energy security than combating climate change".