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    Grid Operations

    Moving electricity, safely and reliably

    We're responsible for operating the power grid, otherwise known as the Alberta Interconnected Electric System (AIES). As electricity moves through AIES, we make sure the system is safe and reliable. To do that, we operate according to Alberta Reliability Standards and the Independent System Operator rules.

    Alberta Reliability Committee

    The Alberta Reliability Committee (ARC) provides us with strategic information about maintenance, performance, operation and grid security. They also help coordinate industry stakeholders in Alberta on issues related to reliability, and get their high-level perspective on the grid. As well, ARC working groups receive feedback on standards, criteria, procedures, rules and processes.

    Most Severe Single Contingency (MSSC)

    For information on the current Engagement, visit the Evaluation of MSSC webpage.

    In February 2015, the ARC held a meeting to discuss the Most Severe Single Contingency (MSSC) as it related to overall grid reliability. The summary of this meeting contains the AESO’s initial review of the MSSC, and its relation to current operating practices.

    Read the meeting summary here:

    MSSC impacts on Alberta balancing authority area operation [Posted: June 17, 2015]

    Reliability Coordination

    If you are an adjacent reliability coordinator that needs access to studies or operating procedures e-mail us at:  Please provide the following information in your request:

    • Full name
    • e-mail address
    • Title
    • RC entity name
    • Access to 1) Studies library,  2) Operating Procedures library or Both

    System Operating Limit Methodology for the Operating Horizon

    We conduct engineering studies to determine operating limits over the operation horizon. Read about them here:

    AESO System Operating Limit Methodology for the Operation Horizon version 5 [Posted: October 4, 2019]

    Read information about intertie available transfer capability and transfer path management here:

    Available Transfer Capability and Transfer Path Management ID#2011-001R

    If you’re a reliability coordinator that needs the system operating limit methodology document before a change becomes effective, or information on system operating limits and interconnection reliability limits, email us at:

    System Restoration

    We manage the bulk electric system in Alberta so it runs safely and reliably. But there is still a risk a blackout could happen. During a blackout, we work with our industry partners to get your power back as quickly and safely as possible. This usually means following a system restoration plan.

    Restoration plans must follow ISO rules or Alberta Reliability Standards.

    If you need to submit a plan, please send a copy for review and approval to and

    Download an example of a TFO restoration plan submittal review request here:

    Example of a TFO email review request