coal power: air pollution

Environmental impacts of coal power: air pollution

Coal plants are the nation’s top source of carbon dioxide (CO2) emissions, the primary cause of global warming. In 2011, utility coal plants in the United States emitted a total of 1.7 billion tons of CO21.  A typical coal plant generates 3.5 million tons of CO2 per year2.

Burning coal is also a leading cause of smog, acid rain, and toxic air pollution. Some emissions can be significantly reduced with readily available pollution controls, but most U.S. coal plants have not installed these technologies.

  • Sulfur dioxide (SO2): Coal plants are the United States’ leading source of SO2 pollution, which takes a major toll on public health, including by contributing to the formation of small acidic particulates that can penetrate into human lungs and be absorbed by the bloodstream. SO2 also causes acid rain, which damages crops, forests, and soils, and acidifies lakes and streams. A typical uncontrolled coal plant emits 14,100 tons of SO2 per year. A typical coal plant with emissions controls, including flue gas desulfurization (smokestack scrubbers), emits 7,000 tons of SO2 per year.
  • Nitrogen oxides (NOx): NOx pollution causes ground level ozone, or smog, which can burn lung tissue, exacerbate asthma, and make people more susceptible to chronic respiratory diseases. A typical uncontrolled coal plant emits 10,300 tons of NOx per year. A typical coal plant with emissions controls, including selective catalytic reduction technology, emits 3,300 tons of NOx per year.
  • Particulate matter: Particulate matter (also referred to as soot or fly ash) can cause chronic bronchitis, aggravated asthma, and premature death, as well as haze obstructing visibility. A typical uncontrolled plan emits 500 tons of small airborne particles each year. Baghouses installed inside coal plant smokestacks can capture as much as 99 percent of the particulates.
  • Mercury: Coal plants are responsible for more than half of the U.S. human-caused emissions of mercury, a toxic heavy metal that causes brain damage and heart problems. Just 1/70th of a teaspoon of mercury deposited on a 25-acre lake can make the fish unsafe to eat. A typical uncontrolled coal plants emits approximately 170 pounds of mercury each year. Activated carbon injection technology can reduce mercury emissions by up to 90 percent when combined with baghouses. ACI technology is currently found on just 8 percent of the U.S. coal fleet.

Other harmful pollutants emitted annually from a typical, uncontrolled coal plant include approximately:

  • 114 pounds of lead, 4 pounds of cadmium, other toxic heavy metals, and trace amounts of uranium. Baghouses can reduce heavy metal emissions by up to 90 percent3.
  • 720 tons of carbon monoxide, which causes headaches and places additional stress on people with heart disease.
  • 220 tons of hydrocarbons, volatile organic compounds (VOC), which form ozone.
  • 225 pounds of arsenic, which will cause cancer in one out of 100 people who drink water containing 50 parts per billion.

1 EIA Data
2 Typical plant assumptions: Capacity=600 MW; Capacity Factor=69%; Heat Rate=10,415; CO2 Emissions Rate=206 pounds of CO2/Million Btu
3 Nescaum. “Control Technologies to Reduce Conventional and Hazardous Air Pollutants from Coal-Fired Power Plants.” March 31, 2011.

Learn More about Our Coal Use

In-Depth Analysis and Reports


We Need Your Support
to Make Change Happen

We can shift our nation away from dirty fossil fuels and toward cleaner, renewable sources of power—but not without you. Your generous support helps develop science-based solutions for a healthy, safe, and sustainable future.