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    GUOC Rates

    The owner of a proposed generating unit or aggregated generating facility with a maximum capability of greater than 1 MW is required to pay a Generating Unit Owner’s Contribution (GUOC). For more information, see Section 7 of the ISO Tariff, Generating Unit Owner’s Contribution.

    GUOC Rates

    Planning Region

    Current GUOC Rate*













    *GST will be applied to the GUOC payment.
    **The current rates are effective January 1, 2023.

    To view the geographic areas of each region, see the Planning Region Map.

    GUOC Estimate Calculator

    To estimate the amount of GUOC that will be required for the current or GUOC rates, enter the planning region and maximum capability in the corresponding calculator below. For more information about the calculation of GUOC, see ID #2023-014T, Generating Unit Owner’s Contribution Calculator.

    Current GUOC Rates

    Contribution Estimate: $2300.01

    This online calculator is designed for convenience and should be used for informational purposes only. The accuracy of the calculator and its applicability to particular cases is not guaranteed. The AESO will issue a GUOC assessment and final invoice which may differ from the estimate generated by this online calculator. The AESO makes no claims, promises, or guarantees regarding the accuracy or completeness of the information provided by this online calculator, and expressly disclaims liability for errors or omissions. Consequently, any reliance placed on the information provided herein is at the user’s sole risk.

    GUOC Rates and Yearly Update Process

    The AESO has published a process document that provides stakeholders details on the new GUOC Rate update process, which it plans to implement in alignment with the 2023 ISO tariff.

    If you have questions about the GUOC Rates, please contact