IMPA, Duke Energy Indiana, Duke Energy Ohio, and the Wabash Valley Power Association 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, provide 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.