Touted by many as the answer to air pollution, greenhouse gas emissions (GHG), and dependence on foreign oil, production of ethanol from plant biomass is rapidly gaining momentum.
Almost every country, it seems, is on the ethanol bandwagon. China, South American and African countries are eagerly following Brazil, the world leader in ethanol production.
Prime Minister Stephen Harper announced that by 2010, 45% of all gasoline sold in Canada will contain 10% ethanol and the rest should contain 5%. For some, the government should have gone even further. The Saskatchewan government, for example, was lobbying for at least a 10% ethanol blend for all gasoline by 2010.
Canada is a minor player in terms of ethanol production. Brazil produces 45.2% of the world’s total (16.5 billion litres according to 2005 figures) from sugar cane, and the United States produces 44.5% (16.2 billion litres) from corn. Ethanol supporters complain that Canada is lagging behind many countries when it comes to legislating the use of ethanol.1
Yet, despite the hype about ethanol, is it all it is cracked up to be? The production of ethanol has become a topic of much debate with its proponents claiming it to be key in solving the energy crisis while critics point to its negative environmental, economic and social impacts.
Ethanol’s supporters often cite the potential for ethanol-blended gasoline to reduce greenhouse gas (GHG) emissions from transportation. The argument is that most currently produced biofuels generally have a positive GHG balance because energy crops can sequester (bind) soil carbon as they grow, thereby taking carbon dioxide out of the atmosphere.
Biofuel production has the added appeal of creating jobs and keeping money within the national economy rather than spending it on imported oil. Brazil can attest to this with savings of about $120-billion over a thirty-year period due to reduced oil imports and avoided interest that would have been paid on foreign debt. And then there are carbon credits which would put ethanol production in good economic stead.
The energy balance
The debate over the energy balance of biofuel production is heated. Critics suggest that for most energy crops, particularly corn, more energy is required to produce ethanol than the energy it can supply. Dr. Pimentel and his colleagues from Cornell University suggest that the production of ethanol from corn is highly inefficient requiring nearly four units of energy per unit of energy used.2
Researchers for the United States National Corn Growers Association see Pimentel’s research as fearmongering and claim that he used old and/or irrevelant data. One study from Minnesota showed that ethanol from corn produced 25% more energy than it consumed.
Ultimately, the energy balance depends on the feedstock used (e.g. corn vs. poplar), the transportation costs, and the energy required for processing.
Food into fuel?
For a whole host of environmental, ecological and social reasons, ethanol production from plant biomass is not the panacea it appears to be. Some critics are cautious about growing crops for fuel rather than for food. Others believe industrial-scale ethanol production (requiring vast acreages of agricultural land) poses a major threat to food production and could lead to mass starvation.
Will we see corn, sugar cane, soybeans, canola and palm oil at the gas pump rather than on grocery store shelves? We could, when food and feed crop prices are low and oil prices are high. Those commodities will go to the highest bidder. Consider this: in 2004, the US used 32 million tons of corn to produce ethanol and although this represented a mere 12% of the country’s corn crop, it would have fed 100 million people. In many developing countries, biofuel production is perceived as an opportunity to provide an income for farmers. Biofuels are one way to decrease imports and foreign debt.
However, countries need to look at the balance between food and feed production, and the benefit from lower oil imports through the production of biofuel. If, for example, the European Union wanted to provide 10% of its energy needs with biofuel, it would have to convert 70% of its agricultural land into energy crop production.1 The US, Brazil and Canada would have to convert about 30%, 3% and 0.3% of agricultural land, respectively.1
As technology is refined, cellulose-based feedstocks could be used, such as corn stalks, woody residues, wood from fast-growing plantations and even leaves. This would reduce the cost of ethanol production and reduce the market impact on food and feed commodities. Still this technology is in its infancy, leaving the real threat of agricultural land conversion to biomass crops.
Biofuel production threatens more than our food supply. Expanding sugar cane production in Brazil into the Amazon basin for biofuel production puts plant and animal diversity at risk. The same could be said for the huge acreage of mono-cultivated corn for fuel in Iowa and harvesting wood from tropical rainforests to use as biofuel.
Corn, the principal feedstock for ethanol in North America, is hardly environmentally benign. It requires intensive inputs of pesticides and fertilizers (which in turn require the use of fossil fuels in their production). Also, conventional corn cultivation is associated with significant releases of nitrogen, phosphorus and pesticides in its runoff. These compounds can make their way into drinking water. There is also increased potential for soil erosion and eventual loss in site productivity. It is easy to see how ethanol produced from corn makes little economic or environmental sense.
The increased demand for wood for ethanol could result in pressure on forests and lead to increased cutting and greater land degradation. Wood biofuel should come from existing wood residues, such as precommercial thinning, harvesting and processing residues, and dedicated woody crops.
Greenhouse gases (GHG) are emitted when fossil fuels are used in the ethanol production process, be it for the production of fertilizers and pesticides used in growing the corn, or for fueling the ethanol production process (e.g. coal or nuclear). Furthermore, when forests are converted to biofuel, the carbon that was stored is released both in terms of the wood that is cut and the increased decomposition that follows in soils.
The goal of society should be to have no or very low emissions, rather than just a small reduction in GHG emissions over the current rate. The increased use of inputs for growing energy crops, the conversion of forested land and the use of fossil fuels for the production of biofuel do not present a likely scenario for achieving this.
The question of genetically-engineered (GE) organisms also arises. For example, Brazil plans to use GE soybeans for biofuel. The use of GE crops has the potential to contaminate non-GE crops. Hybrid poplar or other fast-growing trees can also be genetically modified and thus have consequences in terms of forest ecology.
With increased concentrations of ethanol in gasoline, the production of smog-producing substances will further endanger the health of humans, particularly children, the elderly and the immuno-compromised. Ethanol increases emissions of known carcinogens acetaldehyde and formaldehyde up to 70%. Increased use of ethanol may also increase atmospheric levels of peroxyacetyl-nitrate, a substance that is genotoxic (causes damage to genetic material).
Increased exposure to ethanol may contribute to other health effects including developmental toxicity, central nervous system dysfunction, teratogenicity (birth defects), reproductive disorders and cancer. While data is still lacking, some studies suggest that these impacts on human health may occur at low ethanol exposure.
Researchers in Denmark have suggested that organic farming in that country has considerable potential to provide national bioenergy.3 Biogas, for example, could be derived from livestock manures and from grass/clover production. Some canola oil for biodiesel is already being manufactured but acreage could be increased and alders could be planted. According to their models, organic biofuel crops could lead to a 20% reduction in oil consumption and a 25% reduction in energy consumption for housing and machinery.
Ecologically sound biofuel production should aim, as organic agriculture has done or has tried to do, for a relatively closed energy cycle. At the same time, it should ensure lower energy consumption per unit energy produced, protected water quality, recycling of nutrients, reduced nitrous oxide emissions and increased soil carbon storage.
The Danish study points to the possibility of integrating ethanol production at the small, local scale into existing farms without threatening agricultural land but possibly contributing to a reduction in oil use.
The bigger picture
Even proponents of ethanol generally agree that it is only a small part of the solution. Surely driving less, using mass transport more, and driving smaller, lesspolluting vehicles are key ingredients to a healthier planet and its inhabitants. Redesigning cities to facilitate cycling, walking to work and amenities, and discouraging vehicular traffic is essential to a solution. Sprawling suburbia is not. Perhaps electric and/or solar powered vehicles are part of the answer too. All of these potential solutions require social change which is always more difficult and long-term (i.e. less politically appealing) than a quick-fix solution like a seemingly ‘green’ fuel.
1. Worldwatch Institute and the German Agencies of Technical Cooperation (GTZ) and Renewable Resources (FNR), Biofuels for Transportation: Global Potential and Implications for Sustainable Agriculture and Energy in the 21st Century. 2005. www.oee.nrcan.gc.ca/transportation/personal/vehicle_fuels.cfm?attr=8#ethanol (June 2006)
2. Pimentel, D. 2003. “Ethanol fuels: energy balance, economics and environmental impacts are negative.” Natural Resources Research. 12(2):127–134.
3. Dalgaard,T., U. Jorgensen and I. Kristensen. 2006. “Visions for organic bioenergy production in Denmark.” http://orgprints.org/7633/01/Bioenergy_paper_DARCOFconference2006_0303.pdf
4. Ostertag J. 2006. Local and global biodiesel production: A Carleton County, New Brunswick Perspective. Falls Brook Centre.
Gernstein, S. 1999. “Gasoline Additives Fuel High Prices and Environmental Problems Hearing on The National Sustainable Fuels and Chemicals Act of 1999 Before The Committee on Agriculture, Nutrition and Forestry.”
Grobowski M.S. and J. McClelland. 2003. “A rebuttal to ethanol fuels: energy balance, economics and environmental impacts are negative.” Natural Resources Research 14(3): 120.
Hebert, H. J. 2006. “Ethanol won’t solve energy crisis.” Associated Press, July 11, 2006. www.enn.com/ today.html?id=10839
Pimentel, D. and T.W. Patzek. 2005. “Ethanol production using corn, switchgrass and wood; biodiesel production using soybean and sunflower.” Natural Resources Research 14:65–76.
Other sources of information:
Vehicle Fuels. Natural Res. Can. www.oee.nrcan.gc.ca/transportation/personal/vehicle_fuels.cfm?attr=8#ethanol
Canada’s Biofuels Future. Globe-net (source). www.globe-net.ca/search/display.cfm?NID=2041&CID=2 (July 2006)
Ethanol Production: Facts about ethanol production. Agri-Gate. www.agfinity.com
Biofuels for Transportation: Selected trends and facts. Worldwatch Institute. www.worldwatch.org/node/4081
Food and fuel compete for land. www.peopleandplanet.net/ doc.php?id=2573&PHPSESSID=3e6d06e38b8fe5587340d1f535714031
Food Outlook. The rise in crude oil prices stimulates ethanol-related demand for agricultural commodities.
Alternative Fuels. www.cleanenergy.gc.ca/tech_dict/index_e.asp?ac=95&sc=179&sc_i=0&ac_i=0