Biofuels, a double-edged sword?

The rush to switch from oil to energy derived from plants will drive deforestation, push small farmers off the land and lead to serious food shortages and increased poverty unless carefully managed, according to a United Nations survey of energy crops.

The report points to crops like palm oil, maize, sugar cane, soya and jatropha. Rich countries want to see these extensively grown for fuel as a way to reduce their own climate changing emissions. Their production could help stabilise the price of oil, open up new markets and lead to higher commodity prices for the poor. But the UN urges governments to beware their human and environmental impacts, some of which could have irreversible consequences.

Global production of energy crops is doubling every few years, and 17 countries have so far committed themselves to growing the crops on a large scale. Last year more than a third of the entire US maize crop went to ethanol for fuel and Brazil and China grew the crops on nearly 50m acres of land. The EU has said that 10% of all fuel must come from biofuels by 2020. Biofuels can be used in place of petrol and diesel and can play a part in reducing emissions from transport.

On the positive side, the crops have the potential to reduce and stabilise the price of oil, which could be very beneficial to poor countries. But forests are already being felled to provide the land to grow vast plantations of palm oil trees. Environment groups argue strongly that this is catastrophic for the climate, and potentially devastating for forest animals like orangutans in Indonesia. "Where crops are grown for energy purposes the use of large scale cropping could lead to significant biodiversity loss, soil erosion, and nutrient leaching. Even varied crops could have negative impacts if they replace wild forests or grasslands."

According to the report, the crops could transform the rural economy of rich and poor countries, attracting major new players and capital, but potentially leading to problems. "Large investments are already signalling the emergence of a new bio-economy, pointing to the possibility that still larger companies will enter the rural economy, putting the squeeze on farmers by controlling the price paid to producers and owning the rest of the value train," it says.

The crops are not guaranteed to reduce greenhouse gas emissions. Producing and using biofuels results in some reductions in emissions compared to petroleum fuels, it says, but this is provided there is no clearing of forest or peat that store centuries of carbon.

"Bioenergy provides us with an extraordinary opportunity to address climate change, energy security and rural development. [But] investments need to be planned carefully to avoid generating new environmental and social problems," said Achim Steiner, executive director of UN Environment programme yesterday.