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What Place in Our Energy Future?

(Released April 2009)

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  by Ethan Goffman  


Key Citations




Food Versus fuel? Life Cycle and Indirect Costs of Ethanol


Biofuels have been touted as using what nature has given us to solve our energy problems in a local, environmentally friendly way. Phil New, the president of biofuels at BP, exclaims, "It's only biofuels that can really respond powerfully to both greenhouse gas (GHG) issues and concerns around energy security'" (Bryner).

Yet critics complain that biofuels create a number of problems, requiring energy input to produce and trading off agricultural and environmental assets for fuel. The United Nations decries how "Rapid growth in liquid biofuel production will make substantial demands on the world's land and water resources" (UN 5), a trend that is already happening. Indirect land use, the amount of land displaced from other uses by ethanol production, is a key measure of the efficacy of ethanol, and one very difficult to calculate. It includes not just displaced food, but forest and other natural land that may be cut down to make way for new agricultural land demanded by ethanol production. Argues one scientific paper, "Growing crops for fuel squanders land, water and energy resources vital for the production of food for human consumption" (Pimentel et al).

protester holding corn
A protest against rising tortilla prices, Mexico City, January 2007.
Ethanol use is seen as critical to the recent surge in food prices that was felt around the globe, particularly in poor countries: "Food riots erupted in 18 countries, from Bangladesh to Haiti. About 75,000 Mexicans marched in their capital, accusing the government of 'stealing tortillas'" (Max). A World Bank paper explains that "From January 2005 until June 2008, maize prices almost tripled, wheat prices increased 127 percent and rice prices increased 170 percent" (Mitchell). While the paper blames higher energy prices and other factors for some of this, it concludes that the main trigger "was the large increase in biofuels production in the U.S. and the EU" and cites other studies with similar conclusions (Mitchell). Much of the impact is of biofuel production in crops displaced; that is, fields previously used to grow food crops are now being used to grow corn and other biofuel crops. Local food shortages decrease exports. Government mandates for ethanol in specific parts of the world thus lead to food shortages globally. Still, this situation may be temporary as technology and conservation practices advance: "Agricultural research aimed at improving productivity, conserving water, and building soil fertility can lessen the tension between food, feed, and fuel production by increasing overall agricultural output in a sustainable manner" (UN 34).

In a world worried about impending water shortages, water use is another critical aspect of biofuel impact, one not discussed enough. Crops consume huge amounts of water; indeed "Agriculture currently uses 70 percent of the world's (and 85 percent of the developing world's) available fresh water" (UN 45). Rising global demand for meat, which takes far more water per unit of food produced than do grains, is adding to the pressure. Although the UN foresees no global water crisis for "irrigated agriculture at the global level by 2030," at the local level water shortage is an increasing problem (UN 45). The food versus fuel debate thus extends to the impact on our water resources and must be factored into any analysis of biofuel's costs and benefits. And water is a factor that encompasses both agricultural and environmental issues.

In the media it is GHG emissions that stand at the forefront of environmental worries. Assessing the overall impact of biofuels on these emissions is extremely complicated, and more research is needed. Land use changes, fertilizer content, and beneficial by-products are only some of the factors. For transportation, biofuel production probably has a helpful effect on GHG emissions. Most "studies have found that, even when all fossil inputs throughout the lifecycle are accounted for, producing and using biofuels from current feedstock results in some reductions in GHG emissions" (UN 48), although indirect land use changes the equation. According to the UN, "even the planting and harvesting of 'sustainable' energy crops can have a negative impact if these replace primary forests, resulting in large releases of carbon from the soil and forest biomass" (48). This is already happening; "a February 2007 study in Science showed that corn ethanol could result in nearly twice the greenhouse gas emissions as the gasoline it would replace. As grasslands and forests are converted to agricultural lands, CO2 that had been locked in the soil for millennia is released into the atmosphere" (Boyd).

These negative effects vary greatly between different biofuels; great care must be taken, then, in what kind of ethanol is produced and how it is produced. And the costs are almost certain to decrease; "In the long term, the relative economics of bioenergy will likely improve as agricultural productivity and agro-industrial efficiency improve" and as infrastructure and policies develop (UN 12). Biofuels may only be at the infancy of their use; with better technology and more sophisticated understanding of life cycle and indirect land use, they may still provide the benefits once touted.

ethanol pump
Ethanol Pump
One environmental benefit ethanol does have is in improving local air quality. Such emissions "as carbon monoxide and hydrocarbons are . . . reduced by increasing the ethanol content of transportation fuel" (UN 37). In the United States, currently ethanol is blended into gasoline at a rate of up to 10%, benefiting air quality. An earlier additive, MBTE, was banned in 2000 as a suspected cancer agent. With its clean burning nature, ethanol is now mandated.

However, transportation may not be the best use for biofuels. According to the United Nations, "In the case of electricity generation, biomass combustion to displace coal can reduce GHG emissions even further than using biomass for transport fuels" (UN 48). Thus biomass might be best used to replace coal rather than oil. This is one of many possibilities to consider as biofuel use evolves.

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