Burning questions about biofuels

Biofuel enthusiasts, including the new US president, say food crops can provide a cleaner, greener source of energy than fossil fuels. Yang Fangyi urges caution.

The new president of the United States, Barack Obama, has planned a range of measures to deal with climate change. These include the expansion of the use and production of biofuels. But while biofuels can replace some fossil fuels, the main focus of climate-change mitigation should be reducing fuel consumption and increasing energy efficiency. Biofuels cannot be a major part of the solution – and they may have a negative impact on the climate and the global economy.

Simply put, any organic substance converted into fuel is a biofuel. “First generation” biofuels are already widely available. These include ethanol produced from food crops such as maize, sugarcane and sorghum, and biodiesel from oil-bearing crops like soybeans, oil palms or rapeseed. Tung-oil trees have also been planted for use as biofuel feedstock. Research into “second generation” biofuel technology is also underway. This would mean converting wood cellulose directly into fuel, but the manufacturing processes have not yet advanced to the point where this is possible.

In 2007, 53 billion litres of ethanol and 10 billion litres of biodiesel were produced. However, the cost of planting crops for feedstock is high, and production is rarely profitable or able to compete with oil. In July 2008, with oil prices at a record high, a litre of unleaded petrol cost US$1.08 in the US. At the same time, a litre of maize ethanol still cost almost US$1 to produce. The current downturn has seen the cost of petrol drop to around US$0.44 a litre, meaning biofuel alternatives are even less competitive. The high costs of biofuel production mean that governments are forced to provide subsidies. Currently the only profitable biofuel is the sugarcane ethanol produced in Brazil.

Of most concern is the impact of biofuels on global food security and agriculture. Large areas of farmland are being used for biofuel feedstock production instead of food crops, which raises the price of staple foods. Biofuel expansion is not the only factor behind recent price rises, but it is a major one. Many developing countries are unable to buy enough food – and there is a real threat of starvation for the poor. This has led some to describe the use of food crops for fuel when people are going hungry as a “crime against humanity”.

In theory, biofuels are carbon neutral: burning crops emits the same carbon dioxide that the plants took from the atmosphere during photosynthesis. But in practice, the situation is not so simple, because planting feedstock, processing biofuels and transporting them all require additional energy inputs. A 2008 report from the Organisation for Economic Cooperation and Development (OECD) found that production of sugarcane ethanol in Brazil did reduce emissions by 80% when compared with fossil fuels. However, maize ethanol production in the United States cut emissions by less than 30%. The environmental impact of this first-generation technology was overestimated.

It is also incorrect to assume that planting biofuel feedstock does not cause greenhouse-gas emissions. Tropical forests – crucial carbon sinks – are being devastated as land is cleared for biofuel production. The creation of fields for the planting of soybeans and sugarcane is a cause of deforestation in the Amazon rain forest. Rain forests in Indonesia are being cut down and replaced with oil palm plantations. A paper published last year in the journal Nature described how a “carbon debt” is created, as the destruction of forests often releases more carbon dioxide than is saved by replacing fossil fuels. Environmentalists are also worried by the deforestation occurring in biodiversity hot spots in the Amazon and southeast Asian rain forests. 

Planting biofuel feedstock results in soil loss and water pollution. Soil degradation caused by large-scale fertiliser use is also a prominent issue, and the nitrous oxide released by fertiliser use is a greenhouse gas many times more powerful than carbon dioxide.

First-generation biofuel technology has not provided the environmental benefits its proponents hoped. On the contrary, it has brought its own environmental risks. The European Union has started to make changes to its biofuel policy, and members of the European Parliament voted to reduce the target for biofuel use from 10% of transport fuels down to 6%, and establish a system of certification for sustainable biofuel production. The new US president is starting to take biofuel development seriously: Obama says he hopes to harness the power of second-generation biofuels technology. But it is not yet clear if this technology will be profitable, and biofuels cannot be relied on to reduce greenhouse-gas emissions. The key to achieving that aim will be increasing energy efficiency and expanding environmentally friendly energy sources, such as wind and solar power.

Yang Fangyi is a masters student at the Tropical and International Forestry Institute, University of Gottingen, Germany. Between 2004 and 2008, Yang worked on biodiversity preservation projects for Conservation International in China. He also worked for the Shan Shui Conservation Centre.

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