Clean Energy - If not now, When?

Nitrogen Oxides Pollution from Power Plants

Nitrogen Oxides (NOx) is the generic term for a group of reactive gases, all of which contain varying amounts of nitrogen and oxygen. NOx is formed when fossil fuels, like coal and oil, are burned at high temperatures. NOx contributes to the formation of fine particulate matter pollution, which aggravates respiratory illness and causes premature death in the elderly and infants. 1 NOx also plays a major role in the formation of ground-level ozone (smog) pollution, which causes wide-ranging damage to human health and the environment.

Coal-Burning Power Plants are the Largest Stationary Source of NOx Pollution
Power plants are responsible for over 26% of the NOx emitted in the US each year. Their share of our nation's NOx pollution is exceeded only by the combined total of all highway vehicles. 2

Among power plants, older, dirtier coal-fired plants produce the most pollution. Less than 56% of power plant boilers in the US are fueled by coal. However, these coal-fired boilers generate more than 93% of the power industry's NOx pollution. 3

Loophole Allows Oldest, Dirtiest Power Plants Emit More NOx
When the Clean Air Act was amended in 1970 and 1977, the power industry argued that their oldest, dirtiest, power plants would soon be replaced by new, cleaner, power plants, and therefore should be exempt from new emission regulations. Almost 30 years later, only a handful of the grandfathered power plants have been retired, yet they are still largely exempt from modern, state-of-the-art pollution control requirements.

As a result of this "pollution subsidy," the electric industry is relying on its oldest, dirtiest plants more than ever . For instance, between 1992 and 1998, the amount of electricity generated from dirty and old "grandfathered" coal-fired power plants increased by almost 16%. 4

NOx Pollution From Power Plants Threatens Our Health

Smog (also known as ground-level ozone) is formed when NOx and volatile organic compounds (VOC) combine in the presence of heat and sunlight. Without NOx emissions from sources like power plants, it is likely that dangerous levels of smog would not form in the lower atmosphere. Smog is transported by wind currents and frequently causes health and environmental damage hundreds of miles from where it originates. 5

The EPA provides animated ozone maps that track this harmful pollutant. To see an ozone level map of the US check to EPA's Ozone Map at: www.epa.gov/airnow

The EPA estimates that over 120 million Americans (more than one in three) live in areas with unhealthy air. Ground-level ozone pollution is one of the primary causes of unhealthy air.

• During 1998 alone, the health standard for ground-level ozone was exceeded more than 7,694 times. 6
• On high ozone days there is a marked increase in hospital admissions and ER visits for asthma and other respiratory illness. 7
• Exposure to ozone can make people more susceptible to respiratory infection and lung inflammation. 8
• Long-term exposures to ozone can cause irreversible damage to the lungs that can lead to premature aging of the lungs and chronic respiratory illness. 9
• Fourteen Americans die every day from asthma , a rate three times greater than just 20 years ago.

NOx itself can directly harm health. It reacts with moisture and other compounds to form nitric acid vapor and other harmful particles that are breathed deep into the lungs. NOx particles cause and worsen respiratory disease, such as emphysema and bronchitis, aggravate existing heart disease and can even cause premature death. 10

NOx Pollution From Power Plants Damages the Environment
NOx combines with sulfur dioxide to form acids in the atmosphere that fall to earth as rain, fog, snow or dry particles. This acid precipitation (known as "acid rain") is often carried hundreds of miles by the wind. Acid rain damages forests, causes lakes and streams to become acidic and kill fish, and damages buildings, historical monuments and even cars.

Some of the worst NOx acid damage occurs during the late winter and early spring when accumulated snow begins to melt. These brief bursts of intense acidification during spring downpours and snowmelt cause large scale "fish kills" and are often more deadly to fish populations than longer-term chronic surface water acidity. 11

Too much nitrogen over-fertilizes water and causes algae blooms. When the algae die, they settle to the bottom where the decay process consumes oxygen and kills marine life. This overabundance of algae not only robs oxygen, it also blocks light that fish, shellfish and aquatic vegetation need to survive.

Unfortunately, this problem of over-fertilizing waterways also extends to the ocean. A recent study by the North Carolina Sea Grant found that 46-57% of new nitrogen deposits in the North Atlantic resulted from air pollution. 12 Solving the problem of excessive nitrogen loading of surface waters starts with reducing NOx emissions from power plants.

Regional Haze and Global Warming
NOx emissions from power plants also cause visibility impairment, known as regional haze . Nitrate particles and nitrogen dioxide block the transmission of light and remain suspended in the atmosphere for long periods of time as they are carried by the wind. These light scattering particles degrade visibility on a regional scale in our national parks and other scenic areas. In the Great Smoky Mountains National Park, for example, average visibility is 22 miles; under natural conditions visibility exceeds 93 miles. 13

Another member of the NOx family, nitrous oxide, is a potent greenhouse gas that accumulates in the atmosphere with other greenhouse gases from power plants, such as carbon dioxide (CO2), causing a gradual rise in the earth's temperature. Eventually this warming trend will lead to increased risks to human health, a rise in sea level, and other negative changes to human, plant and animal habitat.

Dirty Old Grandfathered Power Plants Must be Forced to Redce NOx Emissions
The serious damage to our health and environment caused by NOx pollution can be meaningfully reduced only when the loophole for dirty old power plants is closed. Dirty coal-fired power plants must be made to comply with modern pollution control standards. Closing the loophole and capping power plant emissions at reasonable levels will dramatically reduce NOx pollution so we can all breathe easier.

Footnotes:

1) US EPA, "National Air Quality and Emission Trends Report, 1997" (December 1998), p. 20. Available online at http://www.epa.gov/oar .

2) Ibid.

3) US EPA, Acid Rain Program, "National Summary Percent Contribution by Unit Fuel Type." Available online at http://www.epa.gov/acidrain/emissions/us_sum.htm .

6) US PIRG and Environmental Working Group, "Up In Smoke," (Compiled from US Department of Energy (DOE) and USEPA data).

5) US EPA, "NOx, How nitrogen oxides affect the way we live and breathe," EPA 456/F 98-005 (1998).

6) US EPA, AIRS Data. Available at http://www.epa.gov/aqspubl1/annual_summary.html .

7) Abt Associates, Inc., " Out Of Breath, Adverse Health Effects Associated with Ozone in the Eastern United States ," (September 1999).

8) US EPA, "National Air Quality and Emission Trends Report, 1997" (December 1998), p. 25 Available online at http://www.epa.gov/oar

9) US EPA, AIRS Data. Available at http://www.epa.gov/aqspubl1/annual_summary.html .

10) Abt Associates, Inc., "Out Of Breath, Adverse Health Effects Associated with Ozone in the Eastern United States," (September 1999).

11) US EPA, "Health and Environmental Effects of Ground-Level Ozone Fact Sheet," (1997).

12) US EPA, "National Air Quality and Emission Trends Report, 1997" (December 1998), p. 25 Available online at http://www.epa.gov/oar .

13 ) Ibid., p. 37.