Biofuels

Biofuels for transport are liquid or gas renewable energy sources that are produced from biomass and can be used as a substitute or blend for petroleum fuels. Once thought of as a viable green alternative, the debate today over biofuels provokes strong responses from people on both sides, as experts, nongovernmental organizations, and corporate actors are sharply divided concerning their sustainability.

Contrary to general belief, biofuels for transport have been in use since the late 19th century, even though large-scale industrial production is a more recent development. The first national-level program was launched in 1975 in Brazil, with ethanol being produced from sugarcane. The United States soon followed suit, using corn as the prime feedstock. Today, these two examples have been followed by the European Union, India, China, Thailand, and several others around the world. While several different varieties of biofuels are in the market, the only ones that can be currently supplied in adequate amounts are bioethanol and biodiesel. The former is based on crops that are high in either sugar (sugarcane or sugar beet) or starch (maize and corn). The latter is based on plants that contain high amounts of vegetable oil, such as soybean or oil palm.

Types of Biofuels

Promotion of biofuels has been supported worldwide for a wide range of reasons, namely, climate change mitigation, energy security concerns, and rural development stimulation. In terms of main producers, Brazil and the United States account [Page 292]for approximately two-thirds of global ethanol supply, while the European Union (mainly Germany, France, and Italy), Argentina, and the United States are topping the list with regard to biodiesel.

A technician at the U.S. Department of Energy's Argonne National Laboratory in April 2010 compares bacteria samples growing on media containing two different antibiotics. The bacteria was being studied for possible use in biofuel production.

Biofuels from food sources are collectively known as first-generation biofuels. In order to avoid competition with food production, developing second-generation biofuels has been increasingly viewed as a more attractive option, as these are produced from inedible sources, such as woody crops, energy grasses, or even agricultural and forestry residues. However, unlike the easily processed first-generation biofuels, the complex substances found in the woody or inedible tissues of plants are much more challenging to chemically process and convert to energy with currently available methods. Consequently, several technological breakthroughs are still required for second-generation biofuels to become commercially viable. The same is true of third-generation biofuels, which are based on marine algae and seaweeds. A substantive amount of further research and development is required before establishing an economical industrial-scale production of algal biofuels.