Global Warming
Increasing industrial activity and population growth has resulted in a rising concentration of 'greenhouse gases' in the atmosphere that contribute to the 'Greenhouse Effect'. These gases include carbon dioxide, methane, and nitrous oxide. The term 'Greenhouse Effect' refers to the Earth's trapping of the sun's incoming solar radiation, causing warming of the Earth's atmosphere. This offsets the Earth's natural climatic equilibrium, and results in a net increase in global temperatures. 'Global Warming' is a term used to describe the increasing average global temperature.

The term 'Climate Change' refers to a wide range of changes in weather patterns that result from global warming. A substantial increase in the Earth's average temperature could result in a change in agricultural patterns and melting of polar ice caps, raising sea levels and causing flooding of low-lying coastal areas. The Earth's climate is already adjusting to past greenhouse gas emissions, and the average global temperature is expected to rise by 1°C to 3.5°C by the year 2100 (This increase in average temperature is larger than that which has been experienced over the last 10,000 years!). By 2100, the Earth's average sea level is predicted to rise by approximately 50 cm. These phenomena could have serious repercussions on the natural and physical environment, as well as on human health.

Under the Kyoto Protocol, the Government of Canada has committed to reducing its emissions of greenhouse gases by 6% from 1990 levels from 2008-2012. As the difference between the target reductions and business-as-usual scenario is approximately 25% (with the largest proportion of emissions coming from transportation), meeting this target will require a concerted effort on the part of all Canadian citizens and the implementation of many new technologies. Ethanol blends have the potential to substantially contribute to these emissions reductions.

Greenhouse Gases
Under current conditions, use of ethanol-blended fuels as E85 (85% ethanol and 15% gasoline) can reduce the net emissions of greenhouse gases by as much as 37.1%. Ethanol-blended fuel as E10 (10% ethanol and 90% gasoline) reduces greenhouse gases by up to 3.9%. These blends are available at 1,000 retail stations across Canada. By the year 2010, the reductions for E85 and E10 are projected to be 44.5% and 4.6%, respectively. This represents about 1% of the total greenhouse gas reduction required to meet Canada's commitment to the Kyoto Protocol (Levelton Engineering Ltd. and (S&T)2 Consulting Inc., 1999). It is expected that once ethanol is made from cellulose, the greenhouse gas emissions reductions will further improve.

Carbon Dioxide (CO2)
Carbon dioxide from the burning of fossil fuels is the largest single source of greenhouse gases from human activities, representing about half of all greenhouse gas emissions. Use of 10% ethanol-blended fuels results in a 6-10% CO2 reduction and higher levels of ethanol can further reduce the net quantity of CO2 emitted into the atmosphere. The carbon dioxide released from ethanol production and use is less than that absorbed by the plants and soil organic matter used to produce ethanol. The carbon dioxide produced during ethanol production and gasoline combustion is extracted from the atmosphere by plants for starch and sugar formation during photosynthesis. It is assimilated by the crop in its roots, stalks and leaves, which usually return to the soil to maintain organic matter, or to the grain, the portion currently used to produce ethanol. Although the soil organic matter breaks down to CO2 over time, conservation measures, such as reduced tillage, can slow this conversion. Therefore, by increasing organic matter content, the soil is a significant sink for carbon dioxide.

Nitrous Oxide (N2O)
Agricultural grain production for ethanol may generate a slight increase in nitrous oxide (N2O) emissions resulting from heavy fertilizer use. However, research and advances in agricultural technology in grain production are resulting in a reduction of these emissions, often to levels below other common crops. The net effect of ethanol use still results in an overall decrease in greenhouse gas formation.

Where to Get More Information
Canadian Renewable Fuels Association
90 Woodlawn Rd. W.
Guelph, Ontario N1H 1B2
Telephone: (519)-767-0431
Fax: (519)-837-1674
E-mail:
publicinfo@greenfuels.org

References


Rev. 1/12/2000