Friday, January 28, 2011

Switchgrass as a Biofuel

“Virginians are interested in seeing how we can create new markets for agricultural products and become less dependent on foreign sources of oil,” observes John Ignosh, an agricultural byproducts utilization specialist for Extension’s Northwest District. “Developing a bioenergy industry in rural Virginia could serve as a means to reach both of these goals while fostering rural economic development.”

Fossil fuels, the current main source for gasoline, originate from ancient decomposed plants and animals contained in the Earth’s crust. Biofuels, however, are made from plants grown today.

Biofuels are a renewable source as harvested crops can be replanted. They also promise new markets for farm products and potential economic sustenance for rural communities.

Biofuels are increasing in popularity because of oil price spikes, an increased need for energy security, and concern over greenhouse gas emissions from fossil fuels.

The Call for Renewable Biofuels
In 2007 the United States government mandated the annual production of 36 billion gallons of renewable biofuels by the year 2022 in the Energy Security and Independence Act. Of these 36 billion gallons, 16 billion must be cellulosic. Sheila Christopher, a research scientist with the Virginia Water Resources Research Center, explained, "Cellulosic biofuels are made from stems, leaves, stalks, and trunks of plants, none of which are used for food."

Switchgrass is a perennial tall grass. Using switchgrass as a biofuel could reduce erosion and would not affect the world's food market, among other benefits, scientists say.

Corn-based biofuels, or ethanol derived from the fermented sugars in corn, are the most prevalent biofuels today. Corn-based products are more competitive within the food market, causing an increase in food prices. Corn-based ethanol production also can have negative impacts on the environment.

Corn production requires large amounts of nitrogen fertilizer, which can pollute into groundwater. Excess levels of dissolved nutrients such as nitrogen and phosphorus can cause over-productivity in bodies of water when aquatic plants decay and lead to oxygen shortages. Another side effect of corn-based ethanol is the high amount of water required for corn production, straining an already-limited resource.

Cellulosic biofuels have less impact on the environment. Switching from intensive row-crop agriculture to cellulosic biofuels may require less water, reduce erosion, and decrease nutrient leaching, scientists say. Also, cellulosic biofuels, such as switchgrass, would not compete with the food market.

More information:
» 2008: New Technology for Converting Biomass into Hydrogen Fuel
» 2008: Biofuels Feature in Virginia Tech Magazine
» 2008: Scientific American: Grass Makes Better Fuel than Corn

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