Western Energy Imbalance Service Market

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

Southwest Power Pool (SPP) has announced to western utilities its proposal for the Western Energy Imbalance Service market (WEIS) it intends to launch in December 2020. The wholesale electricity market will balance generation and load regionally and in real time. SPP’s previous energy imbalance market went live in 2007 and provided participants with $103 million in benefits in its first year of operation.

SPP will administer the WEIS on a contract basis, meaning 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.

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.