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    Transmission Must-Run service

    Transmission Must-Run (TMR) is generation that is required to be online and operating at specific levels in parts of the province's electricity system to compensate for insufficient local transmission infrastructure relative to local demand. TMR is used to ensure reliability until adequate transmission infrastructure is built in that local area.

    Given the location-specific nature of TMR, only specific units in Alberta may be required to provide TMR. The AESO may enter into a contract with these units when long-term requirements for TMR are identified.

    TMR procurement competition

    Ancillary services, such as TMR, keep the transmission system running reliably and securely. These services are procured by the AESO in a fair, open, efficient, and competitive manner to the extent that a procurement is contestable between market participants.

    Following the identification of a foreseeable need for TMR service in the AESO’s Grande Prairie planning area, a two-stage procurement competition based on the procedure set out in Appendix B of the ISO Tariff, was conducted to enter into a commercial agreement for TMR service. The service period commenced on July 1, 2022, and is for a three-year term.

    The Request for Expressions of Interest (REOI) stage, which launched in March 2022 and included a stakeholder information session, assisted the AESO in identifying parties interested in participating in the competition. The Request for Proposals (RFP) stage opened in April 2022 and closed in May 2022. A contract was awarded in June 2022.  

    The TMR procurement was overseen by a Fairness Advisor at every stage to ensure the competition was administered in a fair and transparent manner, and adhered to all confidentiality requirements, policies and guidelines. 

    To read the Fairness Advisor’s report for the 2022 TMR procurement, please click here.

    TMR service procurement competition documents

    Please direct any comments or questions about the TMR procurement competition to