New Bioenergy Crops for Biofuels
“Using ethanol increases global warming emissions over the use of straight gasoline,” journalist Ed Wallace wrote in 2009 in an article for Bloomberg Businessweek. Seven years later, ethanol is still a hot topic (literally) in the search for alternative energy sources and the struggle against global warming. Ethanol, an alcohol synthesized from corn and other plant materials, is the primary component of current standard biofuels. Biofuels, which are fuels synthesized from plant matter or microorganisms, are a promising source of clean energy, but current methods of synthesizing them are difficult. Ethanol, for example, is predominantly made from corn, which requires large amounts of land and water for proper cultivation. The Renewable Fuel Standard, also known as the ethanol mandate, has required refiners to blend an increasing amount of biofuels into the U.S. gasoline supply since 2005. In the Iowa caucus in January, presidential candidate Ted Cruz ’92 criticized the ethanol mandate for making farms across the United States dependent on subsidies for growing the corn required to produce the ethanol. According to Cruz, the subsidy should be phased out because “businesses can continue to compete, can continue to do well without having to go on bended knee to Washington asking for subsidies, asking for special favors.” Besides the economic disadvantages, ethanol can be even more inefficient than gasoline alone.
Perhaps it’s time to branch out from ethanol to bioenergy crops, which could be more sustainable and efficient in the long-run. According to a University of Illinois Urbana-Champaign research team led by Yang Song, bioenergy crops are low-cost and low-maintenance grasses that are densely-planted and high-yield. The crops are used predominantly to extract certain compounds that aid in the synthesis of biofuels. The researchers have found more efficient bioenergy crops, including grasses called Miscanthus, Alamo, and Cave-in-Rock, all of which pose fewer environmental and logistical risks than ethanol. These grasses have been observed to “leach” less nitrogen than corn. Leaching is the process by which rain or large amounts of water remove compounds like nitrogen from the soil, depriving crops of an important nutrient.
What does this mean from an environmental standpoint? Nitrogen is utilized as a natural fertilizer and nourishes crops, but when it is washed away, it ends up in rivers, lakes, and, ultimately, the ocean. Aqueous nitrogen can lead to the poisoning and possible death of aquatic life, which in turn can hurt industries like fishing, which rely on a healthy aquatic ecosystem. Corn retains nitrogen less tightly, contributing to higher levels of contamination of waterways and greater expenses for farmers. Another advantage of the bioenergy crops over corn is their longer roots. This feature enables the crops to extract more water and nutrients from the ground, meaning that farmers don’t need to water and fertilize the crops as often. Growers would thus save on water, labor, and machinery by transitioning from corn to bioenergy crops.
Growing bioenergy crops could also emit less carbon dioxide than growing conventional crops. Researchers from the University of Southampton in the United Kingdom planted coppice willow, another bioenergy crop, over a large area in Sussex and measured the amount of greenhouse gases produced by the crops. The researchers found that compared to regular grassland, the coppice willow emitted fewer greenhouse gases. These results are encouraging, since they demonstrate another tool countries can use to counter rising emissions, and in some cases, even actively reduce them.
Bioenergy crops are not without significant disadvantages – the ones we’ve addressed can only grow in certain environments. They grow better in climates that are reasonably wet, including the Midwest, but fail in historically dry areas, like the Great Plains. Song found that the optimal locations to grow these bioenergy crops would be eastern Ohio, Tennessee, Kentucky, and the Northern Atlantic states. This information is encouraging because it means these crops could grow alongside corn, which is primarily farmed farmed in the Midwest. However, the crops would deal a blow to agricultural workers in the Great Plains, since these areas prove unsuitable to their production. The crops also have yet to be grown in mass quantities, so cost-efficiency will be an important factor in determining viability.
Regardless of the challenges, bioenergy crops could represent the future of sustainable farming and energy. If the cost of growing these crops proves low enough, we could start to see more biofuels at gas stations around the country. On a global scale, bioenergy crops have the potential to put countries on the path to a low carbon economy.