Generation Resources
We provide 61 communities with a wholesale power supply that is low-cost, reliable, and environmentally responsible.
IMPA’s portfolio of resources includes a mixture of coal, natural gas, renewables, and purchased power. Additionally, IMPA is a joint owner of the Joint Transmission System (JTS), which provides transmission access to approximately two-thirds of the state of Indiana.
Solar
IMPA has developed solar parks throughout the state of Indiana ranging in size from 0.25 MW to 9.9 MW. Most of the parks feature single axis tracking systems, allowing the panels to move and track the sun throughout the day, while other parks rely on fixed tilt panels.
Visit our Resources map to see our current solar parks, and check out our solar parks page to learn more about solar and the energy we produce.
Gibson Station
Gibson Unit 5 is a 625 MW coal-fired baseload generating facility located in southwestern Indiana. The unit was placed in service in 1982 and relies on coal supplied predominantly from southern Indiana. Coal for Gibson Unit 5 purchased from multiple suppliers and delivered to the plant by rail and truck.
Gibson Unit 5 is equipped with particulate, sulfur dioxide (SO2) and nitrogen oxide (NOX) removal facilities. Installation of a Selective Catalytic Reduction (SCR) system for NOX control was completed in 2004, and in 2008, Gibson Unit 5 upgraded its flue gas desulfurization system to increase SO2 removal efficiency.
IMPA has a 24.95% ownership interest, or approximately 156 MW, in Gibson Unit 5, which it jointly owns with Duke Energy and the Wabash Valley Power Alliance.
Prairie State Energy Campus
The Prairie State Energy Campus includes a pulverized coal-fired generating station and associated mine, a rail loop, and water and coal combustion waste storage facilities located in Washington and Randolph Counties in Southwest Illinois. The generating station consists of two supercritical units with a nominal net output capacity of 800 MW each. IMPA’s 12.64% undivided ownership interest in Prairie State is approximately 200 MW.
The Prairie State Energy Campus is situated adjacent to underground coal reserves owned by the Prairie State participants. The coal mine is expected to supply all the fuel for Prairie State for approximately 30 years. Prairie State is among the cleanest coal burning plants in the United States. The plant utilizes state-of-the-art control technologies including low NOx burner controls, SCR for NOx removal, dry electrostatic precipitators, wet flue gas desulfurization and wet electrostatic precipitators.
Trimble County Station
Trimble County Unit 1 is a 514 MW coal-fired electric generating unit located in Kentucky along the Ohio River approximately 20 miles southwest of Madison, Indiana. Trimble County Unit 1 was placed in service in 1990. IMPA has a 12.88% undivided ownership interest in Trimble County Unit 1, which is jointly owned by Louisville Gas & Electric Company (LG&E) and the Illinois Municipal Electric Agency (IMEA). Trimble County Unit 1 is equipped with particulate, SO2, and NOX removal equipment. Installation of an SCR for NOX control was completed in 2003. The SO2 removal facilities were upgraded in 2005 to increase removal efficiency, and a baghouse was installed in 2015.
Trimble County Unit 2 is a nominal 750 MW, supercritical steam unit constructed at the same site as Trimble County Unit 1. Trimble County Unit 2 was placed in service in 2011. IMPA has a 12.88% ownership interest in Trimble County Unit 2, which is approximately 100 MW. LG&E, Kentucky Utilities, and IMEA also hold ownership interests in the unit. Trimble County Unit 2 includes state-of-the-art emissions control, including a SCR, a dry electrostatic precipitator, a bag house, wet flue gas desulfurization, and a wet electrostatic precipitator. The plant is designed to comply with all current emissions regulations and permit conditions and is well prepared to comply with upcoming federal regulations.
Whitewater Valley Station
IMPA assumed operational control of the Whitewater Valley Station (WWVS) located in Richmond, Indiana in 2014. Since then, the station has been utilized by IMPA during peak load periods during the hot summer and cold winter months. WWVS consists of two coal-fired units. Unit 1 has a generating capacity of 35 MW and Unit 2 has a capacity of 65 MW.
IMPA Combustion Turbines
IMPA has seven wholly owned combustion turbines and associated facilities aggregating 419 MW. The combustion turbines include two 41 MW units, placed in service in 1992 and one 85 MW unit placed in service in 2004 located in Anderson, Indiana; two 41 MW units, placed in service in 1992 located near Richmond, Indiana; and two 85 MW units, acquired by IMPA in 2004, located in Indianapolis, Indiana. IMPA employees operate and maintain the combustion turbines located in Anderson and Richmond, while the combustion turbines in Indianapolis are operated and maintained by AES Indiana for IMPA.
All of IMPA’s combustion turbines operate primarily on natural gas. However, the Anderson and Richmond locations also maintain an inventory of No. 2 fuel oil as an alternative fuel in the event of interruptions in natural gas supply, or as an economic option.
Transmission
IMPA, Duke Energy Indiana, and the Wabash Valley Power Alliance are all joint owners of the Joint Transmission Sytem (JTS), which provides transmission access to approximately two-thirds of the State of Indiana.
The JTS includes approximately 1,274 miles of 345-kilovolt (kV) transmission line, 777 miles of 230 kV line, 2,163 miles of 138 kV line, and 3,351 miles of 69 kV line. The JTS also includes 115 transmission substations and 424 distribution substations, which are classified as local facilities. The JTS arrangements include all rights to the use, output, and capacity of these transmission and local facilities.
The JTS Owners are transmission-owning members of the Midcontinent Independent System Operator, Inc. (MISO). The JTS Owners retain ownership of the JTS, but MISO schedules, manages, and oversees the use of the JTS.
In addition to its ownership of transmission facilities, IMPA receives transmission service provided by MISO and the PJM Interconnection, LLC (PJM) under their open access transmission tariffs and under bilateral contracts with other utilities. The JTS, together with these open access transmission tariffs and bilateral contracts, provides IMPA sufficient access to transmission facilities to deliver power and energy under the Power Sales Contracts, to purchase and sell economic wholesale energy, to allow power exchanges with other utilities, and to participate in the MISO and PJM energy markets.