# Southwest Power Pool

Southwest Power Pool (SPP) manages the electric grid and wholesale power market for the central United States. As a regional transmission organization, the nonprofit corporation is mandated by the Federal Energy Regulatory Commission to ensure reliable supplies of power, adequate transmission infrastructure and competitive wholesale electricity prices. Southwest Power Pool and its member companies coordinate the flow of electricity across approximately 60,000 miles of high-voltage transmission lines spanning 14 states. The company is headquartered in Little Rock, Arkansas.

## History

SPP's story began in the early days of WWII, when America was ramping up production of weapons and military supplies. After entering the War, America needed to produce aluminum for aircraft manufacture. Alcoa and Reynolds Metals Company established themselves in Arkansas, which had the largest commercially exploitable bauxite deposit at that time. In 1941, government agency Defense Plant Corporation opened a plant in Jones Mill, Arkansas, with the intent of operating 24/7 to supply the war effort. The government leased the plant to Alcoa for operations.
The Jones Mill Plant alone required 120 megawatts (MW) of electrical power to operate. This exceeded the state's entire generation of 100 MW at peak, excluding outages. Due to the war effort, there was not enough manpower or raw materials to build further electrical generation. Executives of Southwest power utilities decided to pool their generation resources together to ensure the region's reliability and dependability during wartime. The existence of Southwest Power Pool was out of necessity and scarcity. After the war, executives saw the expertise and efficiency that was created and decided to remain a power pool.
Southwest Power Pool, Inc. was formed Dec. 14, 1941, with 11 regional utilities entering into an inter-company agreement. The 11 companies were Arkansas Power & Light, Louisiana Power & Light, and Mississippi Power & Light (subsidiaries of Entergy), Southwestern Gas and Electric and Public Service Company of Oklahoma (now subsidiaries of American Electric Power), Nebraska Power, Texas Power & Light, Southern Light and Power, Oklahoma Gas and Electric, Kansas Gas and Electric, and Empire District Electric.
Here are some other notable events in SPP’s history:
1968 - Became NERC Regional Council
1980 - Implemented telecommunications network
1991 - Implemented operating reserve sharing
1994 - Incorporated as nonprofit
1997 - Implemented reliability coordination
1998 - Implemented tariff administration
2004 - Became FERC-approved Regional Transmission Organization
2007 - Launched EIS market
2009 - Integrated Nebraska utilities
2010 - FERC approved Highway/Byway cost allocation methodology and Integrated Transmission Planning Process
2012 - Moved to new Corporate Center
2014 - Launched Integrated Marketplace Became regional balancing authority
2015 - Integrated System joins SPP
2018 - regional entity operation dissolved
2019 - Launched western reliability coordination services
2021 - Western Energy Imbalance Services (WEIS) market starts

## Members and company status

SPP was incorporated as a nonprofit corporation in 1994 and was approved as a Regional Transmission Organization (RTO) by the Federal Energy Regulatory Commission (FERC) in 2004.
The SPP region lies within the Eastern Interconnection in the central Southern United States, serving all of the states of Kansas and Oklahoma, and portions of New Mexico, Texas, Arkansas, Louisiana, Missouri, South Dakota, North Dakota, Montana, Minnesota, Iowa, Wyoming, and Nebraska. SPP members include investor-owned utilities, municipal systems, generation and transmission cooperatives, state authorities, independent power producers, and power marketers. SPP has many of the high voltage direct current (DC) ties which connect the Eastern interconnection to the Western Interconnection and both of the DC ties to ERCOT Texas Interconnection.
SPP also provides services in the Western Interconnection as of 2019 in Colorado, New Mexico, Wyoming, Arizona, Montana, and Utah. SPP is developing an Energy Imbalance Service Market in the West as well.