Power Supply


Big Rivers joined MISO in December 2009 and become fully integrated December 1, 2010.

MISO is an independent, nonprofit organization that supports the reliable delivery of electricity in 13 U.S. states. This ensures the reliable operation of the regions’s interconnected high voltage power lines that support the transmission of more than 100,000 MW of energy in the Midwest.

MISO was approved as the nation’s first regional transmission organization (RTO) in 2001. The organization is headquartered in Carmel, Indiana with operations centers in Carmel and St. Paul, Minnesota.


Big Rivers has been a member/owner of ACES, one of the nation’s largest electricity traders, since January 2003. ACES operates as an energy risk management and hedge manager. Member/owners like Big Rivers actively participate by utilizing the ACES infrastructure and resources to assess their risks and execute specific, customized portfolio strategies.

Hydroelectric Power

A portion of the power delivered to member cooperatives by Big Rivers is produced by hydroelectric dams operated by the U.S. Army Corps of Engineers. Big Rivers contracts 178 MW from the Southeastern Power Administration (SEPA) which markets power from the dams. This is another example of the commitment of Big Rivers to deliver renewable energy and also to diversify its supply to better protect the interests of the member cooperatives.