CEC compares data on emissions from 1,000 North American power plants
A report comparing emissions data from more than 1,000 fossil-fueled power plants in Canada, the U.S. and Mexico is a first step toward the possible development of a shared emissions inventory for North America. The report, North American Power Plant Air Emissions, was released last week by the Commission for Environmental Co-operation (CEC) in Montreal.
The study is based on data from 2002, the first year for which comparable, facility-specific pollutant information from all three countries could be compiled. The results indicate that a small percentage of facilities release much of the electricity sector's sulfur dioxide (SO2), nitrogen oxides (NOX), mercury and carbon dioxide (CO2) emissions in North America.
In the U.S., for example, some 242 facilities (out of 899 in the database) accounted for 90% of power plant SO2 emissions, with individual facility emissions ranging from a high of nearly 146,000 tonnes to approximately 11,000 tonnes per year. In Canada 90% of SO2 emissions came from 17 out of 38 facilities, with annual emissions ranging from nearly 87,000 tonnes to 13,000 tonnes. Sixteen out of 82 facilities produced 90% of Mexico's SO2 emissions. In Canada, the U.S. and Mexico, the highest NOX-emitting facilities, representing 10% of the total number of facilities in each country, produced 51%, 65% and 52% of total NOX emissions, respectively.
While coal combustion accounts for only 44% of electricity on the continent, it is responsible for 86% of total SO2 emissions from electricity and 90% of NOX. The vast majority of mercury emissions from electricity generation in each country also come from coal combustion.
"This report shows that, site by site, coal-fired power plants are the dominant source of harmful air emissions from the electricity sector in North America," said CEC executive director William Kennedy.
The report also notes that each nation uses its own unique mix of fuels and technologies to produce electricity. The U.S., for example, generates half of its electricity from coal, while Mexico obtains more than two-thirds of its power from oil and natural gas, using coal to produce only gets about 8% of its electricity. By contrast, Canada produces the largest share of its electricity from hydropower.
The data reveal wide variations in the emissions performance of individual fossil-fuel power plants throughout North America. The biggest sources of air pollution are generally clustered in the midwestern and southeastern United States, along with some large oil and coal plants in Mexico.
"Only a relatively few big power plants use modern pollution control equipment for some of these pollutants," said Paul Miller, the report's co-author and the CEC's program co-ordinator for air quality. "For example, there is tremendous potential to use technology to make further reductions in sulfur dioxide emissions, linked to fine particulate matter, and nitrogen oxides, linked to smog."
Miller further pointed out that fossil fuel power plants in Canada, Mexico and the United States contribute 23%, 30% and 39%, respectively, of the three countries' national emissions of CO2, an important greenhouse gas.
"The report is a snapshot of the air pollution and power generation relationship in North America, but we should recognize that many companies have already acted to reduce their environmental footprint," said Kennedy. "In fact, a number of power plants are currently installing new technologies to reduce pollution, and this report helps set a North American benchmark with which we can show their environmental achievements over time."
The report may be viewed on the CEC Web site, www.cec.org More information is also available from Spencer Tripp at 514/350-4331.