Discussions at the Round Table underlined the wide range of performance of biofuels in terms of life-cycle energy and greenhouse gas emission balances. Performance differs between fuels and even for a single fuel and feedstock, performance varies greatly according to production process and farming practice. In the worst cases biofuels result in significantly higher emissions of greenhouse gases than gasoline or diesel.

In this paper, we review some of the basic energy balance and climate change impact issues associated with biofuels. For both the basic energy and greenhouse gas balances of producing and using a range of fuels, and for the increasingly debated and important issues of non-greenhouse gas impacts, such as land, fertilizer and water use, we conclude that an improved framework for the analysis and evaluation of biofuels is needed. These new methodologies and data sets are needed on both the physical and socioeconomic aspects of the life-cycle of biofuels. We detail some of the components that could be used to build this methodology and highlight key areas for future research. We look at the history and potential impacts of building the resource base for biofuel research, as well as at some of the land-use and socioeconomic impacts of different feedstock-to-fuel pathways.

Governments have influenced the development of bio-energy, particularly liquid biofuels (ethanol, biodiesel and pure plant oil used as a fuel), for several decades. This paper discusses the economics of biofuels and provides an overview of current policy measures to support their production and consumption. It discusses also how the different policies supportive of biofuels interact with broader agricultural, energy, environmental and transport policies, and the relative effectiveness of biofuels in achieving objectives in these areas. The paper concludes with several observations and recommendations.

The transport sector is almost fully dependent on oil-derived products and in both the United States and in Europe this sector contributes to about one-third of total energy consumption and about 30% of CO2 emissions. The transport sector is forecast to contribute to 90% of the increase in CO2 emissions projected for the EU in 2010. With the growing use of oil for transport in China, India and other Asian countries, the rush for oil has resulted in increasing oil prices and a push for production of oil substitutes.

The increase in oil prices and the worsening of climate change are fostering biofuels programmes around the world. Brazil has a long tradition in biofuels. The country has been a largescale producer of ethanol since the 1970s. In 2006, ethanol was responsible for 17% of all vehicle fuel supply in Brazil1. Brazil’s ethanol production from sugarcane is also recognised for its economic performance. In 2005, the Brazilian Government launched a biodiesel programme.

Bioenergy, including biofuels, could become a substantial tool for mitigating greenhouse gas emissions, locally and globally, possibly providing a large fraction of global primary energy supply by 2020. Exactly how large that share will be is not possible to predict with any precision, being dependent on a complex array of physical, social, economic, technical (innovation) and environmental factors. In addition, there will be competition for biomass resources between the different bioenergy sectors (electricity, heat, transport) and alternative uses, e.g. for chemical feedstocks and materials. There will be synergies too, particularly arising through advanced polygeneration and biorefinery supply chains that could help to raise primary productivity and raise resource-use-efficiencies.