Western Energy Imbalance Service Market

Quick Links

• May 12, 2021, release announcing Colorado Springs Utilities joining SPP's western market
• Dec. 23, 2020, release announcing FERC's approval of the WEIS tariff
• Nov. 12, 2020, release announcing SPP and stakeholders will consider RTO expansion to the west; study anticipates $49M in annual savings for current and new members
• Feb. 21, 2020, release announcing WEIS tariff filing
• Dec. 12, 2019, release announcing new participants of the WEIS
• Sept. 9, 2019, release announcing the first agreements with participants of the WEIS
• June 17, 2019, release announcing WEIS proposal and design

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 began administering WEIS on a contract basis 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.

The following are participants of the WEIS Market:

• Basin Electric Power Cooperative
• Black Hills Energy (effective April 2023)
• City of Farmington NM Electric Utility
• Colorado Springs Utilities (effective August 2022)
• Deseret Power Electric Cooperative
• Guzman Energy
• Municipal Energy Agency of Nebraska
• Platte River Power Authority (effective April 2023)
• Tri-State Generation and Transmission Association
• United Power, Inc.
• Western Area Power Administration
  • Upper Great Plains West
  • Rocky Mountain Region
  • Colorado River Storage Projects
• Xcel Energy (effective April 2023)

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 maintains reliability of the region’s transmission system and meets demand with the most cost-effective generation available, reducing wholesale electricity costs for participants. Like SPP’s previous markets, the WEIS provides price transparency of wholesale energy, allows parties to trade bilaterally and hedges 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.  

Governance and Stakeholder Involvement

For more than 75 years, SPP has distinguished itself as a stakeholder-driven organization that achieves its business objectives through consensus-building. While SPP’s independent board of directors provides ultimate oversight of the administration of the WEIS market, an open, transparent, and inclusive stakeholder process is a hallmark of our culture and business model. This same approach has been brought to the governance of the WEIS market to provide ample opportunities for stakeholder engagement and to ensure the market remains effective, efficient and competitive.

Stakeholders can stay informed of, and participate in, WEIS Market development through the Western Markets Working Group.

SPP’s Western Markets Working Group (WMWG) is the forum for customers of SPP’s western energy imbalance service market to engage in matters of WEIS Market related governance and strategy and with other stakeholders. Its meetings serve as an open forum for entities looking to learn about SPP or to have a say in the development of the WEIS market in the west.

Attendees may register on SPP.org for WMWG meetings, which may be attended in-person or by phone. Those interested in learning more about SPP’s provision of energy imbalance service in the west are encouraged to register and attend or to contact SPP’s customer relations department.

To stay updated on the WEIS Market, subscribe to the SPP WMWG Exploder. If you do not have an account, you may create one using the Create Account button at the top right of the page.

The Change User Forum (CUF) engages market participants and monitors market and SPP readiness for the western energy imbalance service market. The CUF makes project management and process improvement recommendations to SPP staff and/or the Western Markets Executive Committee.

Want to learn more?

If you are interested in learning more about SPP’s Western Energy Imbalance Service (WEIS) market, training is available. SPP provides several online self-study courses about key features of the WEIS market and participant responsibilities. If you work for an organization that is an active WEIS participant, you already have access. Register or log into the SPP Learning Center. And if you need assistance logging in or are not currently a member of SPP’s WEIS market, contact SPP’s Stakeholder Training Group.