The push is on to use alternative fuel sources to power U.S. vehicles. The 2007 Energy Independence and Security Act takes up the cause -- it mandates the use of 36 billion gallons of renewable transportation fuels by 2022 (see References 1). If every cloud really has a silver lining, then the urgent need to reduce dependence on fossil fuels -- both for environmental and economic reasons -- calls upon American ingenuity to escape this predicament.
The original flex-fuel vehicle was the model T; it could run on ethanol, gas or a combination of the two. By 1917, annual U.S. ethanol production reached 50 to 60 million gallons. In 2008, it reached 7.2 billion gallons. (See References 2) Ethanol's source is plants such as corn and sugarcane. Cellulosic ethanol, rather than consuming food and animal crops for fuel, uses crop residues, including stalks, hulls and wood byproducts to power your car. According to the U.S. Department of Energy, emissions from cellulosic ethanol are up to 86 percent lower than gasoline emissions. (See References 1)
Biodiesel, made from plant oil and animal fat, powers any engine that runs on petroleum diesel, including semis, cars and trucks. Plant sources of biodiesel include soybeans, cottonseeds, sunflowers, peanuts and canola. Some resourceful drivers even use cooking oil recycled from restaurant deep-fat fryers as fuel, and current research points to algae as another source of biodiesel. In addition to being renewable, biodiesel's strong suit is carbon monoxide and hydrocarbon emissions, which are significantly lower than petroleum diesel, according to the DOE. (See References 4 links)
Hydrogen is the first element on the periodic table, and the DOE sees its potential to revolutionize transportation. As a fuel source, it is still in the research stage, but producing it with renewable energy results in virtually pollution- and emissions-free transportation. Even though there are few hydrogen-fueled vehicles on the road, as of publication, the United State's annual hydrogen production of 9 million tons could power 20 to 30 million low- to no-emission cars. (See References 5 links)
Many other alternatives to gasoline are available, several of which are fuels typically used for purposes other than powering vehicles. These include electricity, methanol, natural gas and propane. Researchers are also studying the feasibility of nontraditional fuels, such as biogas, that may increase energy security or reduce vehicle emissions. (See References 3)
- U.S. Department of Energy: Energy Efficiency & Renewable Energy: Ethanol Myths and Facts, 2011
- U.S. Energy Information Administration: Ethanol, 2008
- U.S. Department of Energy: Energy Efficiency & Renewable Energy: Alternative and Advanced Fuels
- U.S. Department of Energy: Energy Efficiency & Renewable Energy: Alternative and Advanced Fuels -- Biodiesel
- U.S. Department of Energy: Energy Efficiency & Renewable Energy: Alternative and Advanced Fuels --- Hydrogen
Suzanna Didier's work appears in online publications including the National Geographic website, SFGate and Local.com. She is an avid cook who lives on a hobby farm, direct-markets organic produce to local restaurants and has taught at the preschool, elementary and college levels. Didier holds a Master of Arts in education from the University of Oregon.
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