Western Energy Imbalance Service Market

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SPP invites utilities to help build an electricity market to serve the west

SPP’s Western Energy Imbalance Service market (WEIS) will balance generation and load regionally and in real time for participants in the Western Interconnection.

SPP will administer the WEIS on a contract basis beginning February 2021. Utilities do not have to be a member of the SPP regional transmission organization (RTO) to participate. The market will centrally dispatch energy from participating resources throughout the region every five minutes, enhancing both the reliability and affordability of electricity delivery from utilities to their customers.

Six utilities have announced they will be participants of the WEIS Market when it launches in February 2021:

  • Basin Electric Power Cooperative
  • Deseret Power Electric Cooperative
  • Municipal Energy Agency of Nebraska
  • Tri-State Generation and Transmission Association
  • Western Area Power Administration
  • Wyoming Municipal Power Agency

SPP’s previous energy imbalance market went live in 2007 and provided participants with $103 million in benefits in its first year of operation.

As the market’s administrator, SPP will maintain reliability of the region’s transmission system and meet demand with the most cost-effective generation available, reducing wholesale electricity costs for participants. Like SPP’s previous markets, the WEIS will provide price transparency of wholesale energy, allow parties to trade bilaterally and hedge against costly transmission congestion. 

In designing the WEIS, SPP leveraged existing constructs in the west and its experience successfully building and operating its own energy imbalance market from 2007-2014, after which the RTO introduced day-ahead unit commitment and other services in the transition to its current Integrated Marketplace.

An overview of the WEIS’ proposed scope and design is available in the Related Documents menu to the right.