Air quality

Completed projects

As part of AES Indiana's commitment to the environment, the company implemented a $600 million multi-emission environmental initiative several years ago to deliver power with as little impact on the environment as possible and maintain compliance with all environmental regulations. AES Indiana works to ensure that its power plants are in compliance with the Clean Air Act and associated regulations regarding the emission of acid rain, ozone, mercury, particulates and haze. The Clean Air Act establishes numerous programs to reduce air pollution and protect public health. 

AES Indiana’s multi-pollutant plan involves several projects targeted to reduce specific types of emissions, including the installation of flue gas desulfurization units (scrubbers) and selective catalytic reduction units (SCRs) on power generation units.

  • AES Indiana installed selective catalytic reduction (SCR) systems to reduce nitrogen oxide (NOX) emissions on three units at its Petersburg and one unit at its Harding Street Station in 2004 and 2005. Additionally, selective non-catalytic reduction (SNCR) were installed on two units at Harding Street Station.
  • AES Indiana completed upgrades to scrubbers at Petersburg Generating Station in 2006 and 2011 to further decrease sulfur dioxide (SO2) emissions.
  • In 2015, AES Indiana completed the conversion of Harding Street Station units 5 and 6 to natural gas.
  • In 2016, the conversion of Harding Street Station unit 7 to natural gas was completed, which eliminated the use of coal at that location.
  • In 2017, AES Indiana completed construction of a new Combined Cycle Gas Turbine (CCGT) plant in Martinsville that replaced previous coal-fired generation units.
  • AES Indiana invested in new emission controls at its Petersburg Generating Station in 2016, including a pulse air fabric filter system (also called a “bag house”), flue gas desulfurization (FGD) system upgrades and continuous emissions monitoring systems. 

Current projects

AES Indiana continues to invest to improve its power plants' performance and to keep rates low. To further reduce emissions, AES Indiana has announced the retirement of some of its older, coal-fired generating units to be decommissioned within the next few years.

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