Chapter 25. Chapter 25: Biofuels

What are the tradeoffs of using biofuels as an energy source?

Why You Should Care

If you pay taxes in the United States, you have helped pay for the federal incentives used to encourage the production of ethanol, predominantly from corn. Ethanol is the same alcohol found in alcoholic beverages and can be used in place of gasoline in vehicles with properly modified engines. Production of ethanol and ethanol-friendly vehicles in the United States expanded in the 2000s through a series of governmental initiatives aimed at reducing the country’s dependence on imported petroleum. On the face, using ethanol seems like a good solution to the energy crisis, but there are trade-offs that some believe make ethanol production as it is done now as environmentally damaging as fossil fuels. The big issue is that most ethanol produced now in the United States comes from corn. Large amounts of land that could be used to produce human food are instead being used to grow corn that no one will eat. Furthermore, growing and transporting corn requires machinery and vehicles that run on petroleum-based fuels, and fermenting corn requires heating it with electricity that is usually produced by coal-burning power plants. The cooking and processing steps required to ferment corn into ethanol require more electricity than most of the other crops used for producing ethanol. Other crops and methods can be used for producing ethanol more sustainably, but current policies favor the growing of corn.

The story of ethanol and corn isn’t unique. Most biofuels have some drawbacks that limit their usefulness: Their production requires as much or more energy as is produced;producing them on a large scale would be too costly or require too much arable land; or they are simply unsavory (such as the current companies proposing to convert human sewer sludge into ethanol). Does this mean that we should abandon our efforts to develop biofuels? No. Just as with the renewable/sustainable energy sources described in the last chapter, it will probably take a variety of biofuels to meet our energy needs.

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