Dartmouth Engineer - The Magazine of Thayer School of EngineeringDartmouth Engineer - The Magazine of Thayer School of Engineering

Answers to the Growing Fuel Debate

Biofuels don’t have to compete with food.

By Nathanael Green and Professor Lee Lynd Th’84

Biofuels were riding a wave of popularity only a few months ago, but now suddenly they’re being roundly condemned in light of rising food prices and recent studies showing that biofuel production can exacerbate climate change. While these concerns should motivate greater efforts to do biofuels right, we must not throw the biofuels baby out with the bathwater — especially given the dearth of viable alternatives to power a sustainable and secure transportation sector. Rather than retreating from current policies, which do more for smart biofuels than many realize, the nation should follow California and Massachusetts in building on this foundation.

Switchgrass The current rise in food prices is causing a humanitarian crisis that we must address. But if we want to fix the problem, we first need to understand what’s behind it. Biofuels are a modest part of the food price picture, consuming only four percent of world grain, and there is little evidence that food prices would be much lower if we did not produce biofuels. The primary reasons for skyrocketing food prices include our rising energy costs, increased demand for meat in developing countries, drought, and misguided national and international agricultural policies.

Global warming is also a crisis, and two recent papers in Science identify issues that we must pay attention to if biofuels are going to contribute to lowering global warming pollution. The papers point out that if the demand for biofuels causes unmanaged forests or grasslands to be converted to row crops, we must account for the global warming pollution released during that conversion, and that these emissions can overwhelm the benefits of displaced gasoline or diesel consumption. There are solutions, however.

We can make biofuels from non-food biomass (woody material, grasses, stalks, and stems), while also producing this “cellulosic” biomass in ways that neither compete with food production nor cause increased global warming pollution that comes from converting wild landscapes to row crops. In other words, using the right part of plants and producing them in the right ways take biofuels out of the food price equation and makes them part of the solution to global warming.

Such cellulosic biomass is available from a greater diversity of sources than row crops, including wastes, land that cannot grow food crops or is not needed for food production, and new approaches that coproduce food and biofuel feedstocks. Several studies have shown that wastes from the forest-products industry, crop residues, and winter cover crops could provide hundreds of millions of tons of biomass annually — and certainly enough to comply with the recently adopted 21-billion-gallon federal renewable fuel standard for “advanced biofuels.”

The renewable fuel standard, signed into law in December 2007 as part of the Energy Independence and Security Act (EISA), is the first biofuels policy to mandate a shift in our production practices in a way that directly addresses global warming pollution. And by promoting sustainable cellulosic biofuels, it will indirectly address the food production challenge. EISA establishes minimum global warming pollution standards for biofuels and critical land-use safeguards. New biofuels projects that increase global warming emissions — including emissions from land conversion — are not permitted. Most of the mandated 15 billion gallons of corn ethanol production capacity required by the act is already in place or under construction. As expansion beyond this level is unlikely to be favored by either market forces or regulation, the ceiling of corn ethanol production appears to be in sight.

The low-carbon fuel standard, first embraced by California and recently by Massachusetts, goes beyond setting a minimum standard and rewards the best solutions. This approach requires that oil companies reduce the average global warming pollution of their fuels, but lets the market decide the best mix of options. Biofuels that provide the most reductions will certainly play a big role, but so can other technologies, such as vehicles that use electricity or natural gas.

But along with reducing demand for liquid fuels, we need to find new ways to sustainably produce them. A major focus of the renewable fuel standard is expanded production of cellulosic biofuels. Farmers and producers involved in the existing biofuel industry are generally open to such an expansion, as long as they are not left holding the bag.

Building on the renewable fuel standard and state-level leadership, the nation should establish a federal low-carbon fuel standard as part of comprehensive climate legislation. We also need to realize that better biofuels policies are no excuse for not addressing world hunger head on through better agriculture and food aid policies. More generally, we should go beyond all-or-nothing headlines and pursue a transition to biofuel strategies that realize the compatible objectives of replacing oil, expanding opportunities for existing producers, and securing both food supplies and a sustainable future.

Nathanael Greene is a senior policy analyst for the Natural Resources Defense Council. Thayer Professor Lee Lynd is co-founder and chief scientific officer of Mascoma Corp., a start up that is working to produce cellulosic ethanol efficiently and cost-effectively.

A shorter version of this article was published in the May 11, 2008 Minneapolis Star-Tribune.

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Categories: Features

Tags: climate change, energy, entrepreneurship, faculty, research

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