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Biofuel Examples

The growing problem of carbon dioxide emissions and the difficulties of relying on foreign oil for power and transportation have sparked renewed interest in biofuels, which are viewed as more environmentally-friendly fuel sources. Biofuels are derived from organic matter that is still living or was living in the recent past. Over time, these fuel sources could become viable for both producing electricity and powering vehicles, but so far, no biofuel has managed to replace significant amounts of traditional fuels, either in the transportation sector or in electricity generation.

Biofuel Background
- Since the origins of automobiles, people have been aware of the possibility for using vegetable matter or biomass as a fuel source. Even the first Model-T from Henry Ford could run on corn-based fuel. By raising energy-dense crops like sugar or corn, then allowing it to undergo fermentation, it is possible to derive a fuel that won't produce as much carbon emissions as fossil fuels do, whether they are used for transportation or for generating electricity.
Ethanol
- Ethanol is a biofuel derived from corn. All cars are capable of running on ordinary gasoline mixed with ethanol, at mixtures of up to 10 percent ethanol. Using ethanol would significantly reduce carbon emissions. However, ethanol is not a very efficient fuel source. Growing corn requires substantial amounts of energy and land. Government subsidies for corn lead to overproduction of corn by distorting market price signals, flooding the international food market with cheap corn. Brazil covers 40 percent of its transportation needs with sugar-based ethanol, but the subsidies and resources spent on sugar production have significant negative environmental effects. In 2005, the United States produced 4 billion barrels of ethanol.
Biodiesel
- Biodiesel is a vegetable oil-based replacement for ordinary diesel. In the United States, biodiesel is mainly derived from soybeans, although other sources, such as animal fat, algae, and even kitchen grease can produce biodiesel. Biodiesel burns much more cleanly than diesel, reducing emissions of carbon and other toxic gases. Biodiesel has many of the same problems as ethanol, in terms of efficiency and reliance on a single crop. Currently, the biodiesel industry in the United States is small, even compared to the ethanol industry. In April 2013, the industry produced 106 million barrels.
Other Biofuels
- There are many other biofuels that can potentially replace gasoline, but have not yet reached full development or production. Examples include oil produced by specially-engineered algae, which produce extractable oil as a natural part of their metabolism. However, an algae-derived oil process that produces more energy than it consumes has not reached the market. It is also possible to produce wood diesel and ethanol from the biomass in cellulose, the substance that encases plant cells. Current research for this process focuses on accelerating the growth cycle of plants that are rich in cellulose. For example, one recent study from the University of Maryland and Bowie State University examined the potential for using nitrogen fertilizer and genetics to make poplar trees grow faster and produce more usable cellulose.

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