Biofuels

A biofuel is a solid, liquid, or gaseous fuel made from crops or trees and their residues, human and animal wastes, and algae. In many parts of the world, biofuels are the primary or only source of fuel. Concerns about global climate change, high oil and gas prices, and energy security have increased interest in biofuels over the past decade. Consequently, key questions have been raised regarding biofuels utilization:

• To what extent are biofuels economical? Because the market for biofuels is still emerging, and long-term oil prices are unknown, it is difficult to calculate the true cost of biofuels. Further complicating the situation is the wide mix of subsidies and taxes for both biofuels and petroleum products.
• What are the impacts of biofuels on food prices? While it is clear that not all biofuels compete with foodstuffs, there is concern that agricultural crop-based feedstocks such as corn do.
• What are the environmental impacts of increased biofuel production? Current biofuel production practices typically require extensive inputs, such as fertilizers and water, which have damaging environmental and ecological side effects. Two other key issues that must be considered are the impacts stemming from land use changes that often occur with increased biofuel production and the ratio of energy return on investment in biofuel production.
• How carbon neutral are biofuels? While biofuels allow for a closed-carbon cycle, initial land use change (e.g., turning forests into agricultural land) can emit significant amounts of carbon dioxide into the atmosphere. Another concern is the quantity of petroleum products required to harvest and process some biomass feedstocks.

Current technological and economical research is primarily focused on the creation of alcohol (especially ethanol) and biodiesel as fuel for vehicles. Ethanol and other alcohols can be used as substitutes in gasoline engines, although some engines require modification. Biodiesel is used in diesel engines. Pure ethanol (biodiesel) is [Page 202]commonly referred to as E100 (B100), and a blend of 20% ethanol (biodiesel) and 80% gasoline (diesel) is E20 (B20). In 2006, global ethanol production was 10.6 billion gallons, 90% of which was produced in Brazil and the United States. One billion gallons of biodiesel were produced in 2006—75% by the European Union (EU) and 13% by the United States. However, Malaysia and Indonesia have begun investing in biodiesel production and will likely become much larger producers in the next decade. Case studies of Brazil, the United States, Germany, and Malaysia are presented below.