Igniting Cellulosic Biofuel Production

If produced in a sustainable manner, biofuels have the potential to reduce greenhouse gas emissions, diversify sources of transportation energy, and support a dynamic agricultural economy—both in the U.S. and abroad. In the wake of the ongoing global food crisis, arguments have flared over the impact of diverting some agricultural products out of the food supply and into gas tanks. Biofuel production does have an effect on food prices, though estimates vary from 2 to 30 percent of recent price increases. In order to produce biofuels that provide a net benefit for the environment and but do not compete with food crops, producers in the U.S and around the world need to scale production of cellulosic biofuels, particularly those made from abundant waste materials and crops that do not compete with food.

Cellulosic biofuels, unlike ethanol derived from corn starch, are made from the durable molecules—cellulose—that comprise the woody part of common plants. Not only does the production process result in less greenhouse gas emissions than the process for making ethanol from corn, there are hundreds of millions of tons of biomass feedstocks available every year in the U.S. for cellulosic ethanol that would otherwise be discarded as waste.

What is clear is that we need better biofuels before we need more biofuels.

Two congressional hearings this week will address U.S. production of biofuels. Today, the Rural and Urban Entrepreneurship Subcommittee of the House Small Business Committee focuses on the role of small businesses and farms in developing the second generation of biofuels. On Thursday, the Senate Natural Resources Committee will address the relationship between biofuel production and food prices.

U.S. Secretary of Agriculture Ed Schafer currently cites USDA statistics indicating that increases in biofuel production are responsible for only 2 to 3 percent of recent spikes in food prices; the International Monetary Fund estimates that the impact is 20 to 30 percent. As Jake Caldwell, Director of Agriculture and Trade at the Center for American Progress, explained in a recent “Food Price Crisis 101,” the causes of the increase in food prices around the world are myriad and complex. The soaring costs are a combination of changing global diets, climate change and droughts, steep increases in energy costs, as well as diversion of grains out of the food supply and into production of first generation biofuels.

But regardless of the impact on food, first generation biofuels do not necessarily reduce greenhouse gas emissions. Earlier this year, a pair of studies published in Science argued that changes in land use resulting from increased biofuel production on cropland can result in higher life cycle greenhouse gas emissions for biofuels, as carbon-storing wilderness is moved into cultivation to keep up with demand for food crops.

The Energy Independence and Security Act of 2007 contains a Renewable Fuels Standard stipulating that by the year 2022, the U.S. will produce 36 billion gallons of renewable biofuels. At that time, 15 billion of those gallons are to come from conventional biofuels derived from corn starch. Twenty-one billion gallons are to come from “advanced biofuels,” which achieve greenhouse gas reductions of at least 50 percent compared to a baseline for lifecycle emissions through the entire production process and on to combustion in cars and trucks. Sixteen billion gallons of those “advanced biofuels” must be “cellulosic biofuels,” which achieve lifecycle emissions reductions of at least 60 percent compared to the baseline. The legislation also stipulates that calculations of lifecycle emissions account for significant land use changes, and all biofuels must have lifecycle greenhouse gas emissions at least 20 percent less than gasoline.

To produce those billions of gallons of renewable fuel while simultaneously reducing the carbon footprint of what we burn in our tanks will require a significant amount of sustainably-produced biomass. Two primary sources include waste residue from agriculture and forestry, as well as dedicated energy crops grown on degraded land not suitable for crop production.

Estimates from David Tilman of the University of Minnesota indicate that the U.S. has abundant sources of alternative cellulosic feedstocks that do not compete with food for fertile land. He projects annual totals of 270 to 430 million tons per year of biomass from: dedicated perennial energy crops grown on the least productive or least sensitive abandoned lands; corn and wheat residues; forestry slash, thinnings, urban waste wood, and mill residues; and reclaimed paper waste. He calculates that appropriately selected and diverse crops of miscanthus, switchgrass, and mixed prairie grasses could yield 20 to 32 billion gallons of ethanol per year and achieve greenhouse gas emissions reductions of at least 50 percent.

Farmers and rural communities in the U.S. can benefit from the sustainable production of this renewable fuel. Research indicates that locally-owned production plants make an economic contribution to the community that is 56 percent higher than plants owned by absentee corporations.

But next generation biofuels can reduce dependence on foreign oil imports in the U.S. and abroad. In several, but not all developing countries, the development of a broad-based, socially responsible, and sustainable bioenergy industry has the potential to harness substantial agriculture, land, water, and labor resource advantages of those nations. The sustainable production of biofuels will require appropriate climatic and soil conditions, water resources, land availability, transportation and electrical infrastructure, and labor, but an increased emphasis on bioenergy can provide a unique economic development platform. A growing bioenergy industry has the potential to rapidly scale-up agricultural production, diversify crops, expand industrial and transportation infrastructure, and provide new sources of income and jobs in rural communities.

To ensure the growth of sustainable biofuels markets at home, the Center for American Progress also proposed a “Voluntary Renewable Fuels Certification Program,” which informed provisions of this year’s Farm Bill that provide incentives for a transparent system that certifies biofuels produced in a sustainable manner with reduced lifecycle greenhouse gas emissions. CAP has also proposed a Low-Carbon Fuel Standard, a technology-neutral policy that would mandate a 10 percent reduction in the lifecycle emissions from transportation fuels by 2020. These proposals link our nation’s agriculture with the production of renewable energy, fueling our entire economy towards a low-carbon future.

Tags: biofuels

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