Environmental Aspects

Approximately two-thirds of the electricity generated in Maryland comes from combustion of fossil fuels (coal, oil, and natural gas). The process of burning fossil fuels produces many different air polluants including nitrogen oxides, sulfur oxides, mercury, volatile organic compounds, and particulates. Air pollutants eventually return to the earth’s surface and are deposited directly on the landscape and in bodies of water – or can be carried into streams, rivers, and larger water bodies, such as the Chesapeake Bay (the largest estuary in the United States), thus affecting a broad array of animal and plant life.

Reducing Environmental Impacts

Nationwide, power plants contribute about one-fifth of all NOx, roughly two-thirds of SO2, nearly one-half of mercury, and close to 40 percent of CO2 emissions. In 2006, the Maryland Legislature passed the Healthy Air Act, which establishes caps for NOx, SO2, and mercury for most of Maryland’s coal-fired power plants. This law requires those coal-fired plants that were grandfathered under the Federal Clean Air Act of 1970 to install modern pollution control equipment.

The act also requires Maryland to become a full participant in the Regional Greenhouse Gas Initiative (RGGI) by 30 June 2007, joining the Northeastern states of Connecticut, Delaware, Maine, New Hampshire, New Jersey, New York, and Vermont. The RGGI is developing a plan to cap carbon dioxide emissions from power plants at 1990 levels beginning in 2009, and to reduce emissions by 10 percent from those levels by 2018.

Besides emission reductions from clean coal technology and emission controls, power plant operators are utilizing various methods to minimize environmental impacts other than just those related to air quality. For instance, more than 700,000 tons of combustion products generated in Maryland, such as fly ash, are beneficially used each year. Also, in order to minimize impacts on other water users and on aquatic life, recently constructed and proposed power plants are incorporating innovative techniques into their water management designs – techniques such as dry cooling, hybrid dry cooling, or the use of collected stormwater or treated wastewater instead of withdrawing surface and/or groundwater.

For more information on any of these environmental topics, please refer to the PPRP report entitled “Maryland Power Plants and the Environment (CEIR-13),” dated January 2006. To download the report, visit our website at: www.dnr.state.md.us/bay/prrp