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    View all stakeholder engagements

    Bulk and Regional Tariff Design

    Key dates

    Recent materials posted

    Filing extension request approved 

    On June 1, 2021, the Alberta Utilities Commission approved the AESO's extension request and directed that the AESO file its bulk and regional tariff application on or before October 15, 2021.


    The purpose of this engagement is to work with stakeholders to redesign the ISO tariff to ensure rates appropriately and fairly recover the sunk costs of the current transmission system and send efficient price signals to guide investment and electricity consumption decisions. Specifically, the AESO is considering the monthly coincident peak (12-CP) bulk cost recovery methodology. The treatment of energy storage in the ISO tariff is also in scope for this engagement, as the chosen path for treatment can have interactions with rates for system cost recovery.


    The AESO has been engaging with stakeholders since early 2018 on bulk and regional rates to understand and analyze the issue of recovering sunk transmission costs through the 12-CP mechanism as directed by the Alberta Utilities Commission ("Commission") in the June 29, 2018 Ruling in Proceeding 22942: AESO 2018 ISO Tariff Application.


    The scope of this engagement will be focused on the development of a tariff rate design for bulk and regional charges and will include tariff treatment of storage. The following topics are out-of-scope and will not be discussed as part of this engagement:

    • Participant-Related Costs for DFOs (Substation Fraction) and DFO Cost Flow-Through
    • Rates Update Applications
    • Other 2018 GTA Decision and Corresponding Compliance Filing Items
    • Adjusted Metering Practice implementation plan
    • Options or opportunities outside of the ISO tariff

    Stakeholder engagement and filing schedule

    • Session 1<br>March 13, 2020

       Session objectives

      • Present rate design options for bulk and regional cost recovery with rate objectives assessment
      • Provide rate design analysis tools
      • Review, respond to clarifying questions and collect initial input on options
    • Session 2<br>Sept. 24, 2020

      Session objectives

      • Review and gain acceptance on process and approach to complete a rate design
      • Understand current state rate design
      • Reconfirm tariff rate design objectives and balance of trade-offs
      • Understand rate design bookends
      • Identify initial implications of rate design bookends
      • Understand energy storage treatment options and considerations
      • Provide technical clarity around rate design bookends
    • Tech. Session I<br>Oct. 14, 2020

      Session objectives

      • Ensure stakeholders understand the mechanics of the rate bookends
      • Enable stakeholders to evaluate the impacts of the rate bookends on their sites
      • Assist stakeholders in assessing the materiality of changes to their invoices
      • Ensure stakeholders are equipped to present and/or understand rate design options at the Oct. 22, 2020 stakeholder session
    • Session 3<br>Nov. 5, 2020

      Session objectives

      • Stakeholders to present and discuss alternative rate design options, including energy storage options and implications
      • Understand which rate design options stakeholders support and why
    • Session 4 <br>Dec. 10, 2020

      Session objectives

      • Understand common themes across stakeholder rate design proposals and the AESO rate design bookends
      • Understand areas of agreement and disagreement and why
      • Introduce mitigation conversation to foster/build understanding
    • Session 5<br>March 25, 2021

      Session objectives

      • Present preferred rate design, including energy storage treatment, to stakeholders
      • Present and discuss path to achieving minimal disruption
      • Present bill impact summary and assumptions
      • Provide Bill Impact Tool
      • Begin to discuss implementation considerations
    • Tech. Session II<br> March 31, 2021

      Session objectives

      • Review how to use the Bill Impact Tool in order to:
        • Enable stakeholders to evaluate the impacts of the rate design and mitigation on their sites; and
        • Enable stakeholders to assess the materiality of changes to their invoices
      • Respond to stakeholder questions
    • Targeted Mitigation <br>March-June 2021<br>

      Targeted mitigation engagement purpose and objectives

      The AESO's overall purpose of this targeted mitigation engagement is to work with the stakeholders most heavily impacted (“impacted parties”) by the preferred Bulk and Regional Tariff rate design to identify a path to a minimally disruptive transition to the new rate design. The impacted parties are those with an estimated transmission cost impact of greater than 10 per cent increase under the AESO's preferred tariff redesign.

      The AESO's specific objectives of this engagement include:

      • Reach a shared agreement on a temporary mitigation option that supports ‘a path to minimal disruption’
      • Engage efficiently and actively at the table to progress conversations forward
      • Achieve regulatory efficiency in the resulting AUC proceeding by putting forward a solution that is acceptable to all or most of the impacted parties, the AESO and the broader stakeholder group
    • Session 5B (DOS)<br>May 20, 2021<br>

      Session purpose and objectives

      The purpose of this session is to engage stakeholders in a discussion of the AESO’s demand opportunity service (DOS) modernization recommendation to allow expanded eligibility (e.g., energy storage). The specific objectives include:

      • Present additional background on the AESO’s DOS – what it is, the service it provides and how it operates today
      • Share our learnings on DOS modernization stakeholder feedback
      • Present and discuss the AESO’s DOS modernization recommendation for the purpose of seeking stakeholder feedback on the recommendation
    • Session 6A<br>June 3, 2021<br>

      Session purpose and objectives

      The purpose of this session is to engage stakeholders in a discussion of Session 5 stakeholder feedback or follow-up and key questions raised by the Alberta Utilities Commission (AUC) staff, and to provide additional clarity and build mutual understanding of the AESO’s preferred rate design and stakeholder concerns. The specific objectives include:

      • Share our learnings on Session 5 stakeholder feedback or follow-up
      • Present and seek stakeholder input on additional information on preferred rate design, including analysis of the potential response to the incentives provided in the rate design
      • Present responses to key questions raised by AUC staff
      • Seek to understand outstanding stakeholder concerns
    • Session 6B<br>June 24, 2021

      Session purpose and objectives

      The purpose of the session is to engage stakeholders in a discussion of the AESO’s targeted mitigation discussion outcomes, Session 5B (DOS) and Session 6A stakeholder feedback, and areas of alignment. The specific objectives include:

      • Provide an overview and seek stakeholder input on the outcomes of the targeted mitigation engagement
      • Share our learnings and seek stakeholder input on Session 5B (DOS) and Session 6A stakeholder feedback and areas of alignment
      • Present and discuss implementation considerations
      • Seek to understand outstanding stakeholder concerns
    • Rate Sheets <br>Sept. 7-21, 2021<br>


      The purpose of the written consultation is to seek stakeholder input on the clarity and effectiveness of the proposed drafts of the following Bulk and Regional Preferred Rate Design tariff components:

      • Tariff Rate Sheets
      • Demand Opportunity Service (DOS) Rate Sheet
      • Tariff Terms and Conditions
      • DOS Proforma Agreement
    • Engagement Survey<br>Sept. 23-Oct. 7, 2021


      The purpose of the survey is to seek stakeholder input on the overall Bulk and Regional Tariff Design engagement process to guide the AESO as we continuously work to improve how we engage stakeholders to ensure our approach allows stakeholders’ needs and interests to be consistently, transparently and meaningfully considered.

    • B&R Application<br>Oct. 15, 2021

      The AESO will file its Bulk and Regional Tariff Application with the Alberta Utilities Commission (AUC) putting forward its preferred rate design and DOS modernization on or before Oct. 15, 2021.

    For information on the Tariff Design Advisory Group (TDAG) which was disbanded in January 2020 please click here.

    If you have any other questions, please contact and subscribe to our stakeholder newsletter for updates.