Episode 152: How do coal-fired power plants use water?
Meagan Mauter, a professor at Carnegie Mellon University, discusses the role of water in the energy industry as well as the various technologies being developed to treat wastewater to minimize energy and environmental impacts.
Quantity, Quality, and Availability of Waste Heat from United States Thermal Power Generation from the American Chemical Society
Water Treatment Capacity of Forward-Osmosis Systems Utilizing Power-Plant Waste Heat from the American Chemical Society
Effluent Guidelines from the Environmental Protection Agency
MODERATOR: Have you wondered why coal-fired power plants are often near water? On this week’s Energy Bite, Megan Mauter, a professor at Carnegie Mellon University, has some answers.
MEAGAN: In previous Energy Bite episodes, we’ve talked about the water-energy nexus – how water is often essential to energy production. Coal-fired power plants use water for a number of in-plant operations including cooling, boiler make up water, and sometimes for removal air pollution like sulfur dioxide. As the water is used for these operations, it can gather salts and metals naturally present in coal, including mercury, arsenic, boron, selenium, and chlorides.
Until recently, much of this water was discharged to the environment without treatment. Upcoming US Environmental Protection Agency regulations, called Effluent Limitation Guidelines or ELGs, will require that the water is treated prior to discharge.
MODERATOR: Are there any disadvantages to treating this water?
MEAGAN: Water treatment processes consume both energy and chemicals. So treating this water may reduce the efficiency of electricity generation and increase air pollution emissions associated with auxiliary power consumption and chemical manufacturing. At Carnegie Mellon, we are working to develop water treatment technologies that use waste heat available at coal fired power plants to minimize this potential adverse environmental and energy impacts.
MODERATOR: Are you concerned about the wastewater discharged from coal power plants? Take our poll, see the results, and ask your energy questions at Energy Bite dot org.