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    Previous loss factors and calibration factors

    • 2018

      2018 loss factors

      Loss factors are used to determine the transmission losses charges that apply to system access service under the following rates of the ISO tariff:

      • Rate STS, Supply Transmission Service
      • Rate XOS, Export Opportunity Service
      • Rate IOS, Import Opportunity Service
      • Rate DOS, Demand Opportunity Service

      Notice to stakeholders: The AESO has encountered unanticipated issues while preparing the input data for and updating the software for the 2019 loss factor calculations. The AESO is unable to publish 2019 loss factors by the deadline of November 7, 2018, established in the Loss Factor Rule. The AESO will provide further information to stakeholders when these issues have been addressed and when an expected date for publishing 2019 loss factors has been established. The AESO anticipates requesting forbearance from the Market Surveillance Administrator (MSA) in respect of any related non-compliance with the Loss Factor Rule.

      The AESO must establish and maintain loss factors in accordance with section 501.10 of the ISO rules, Transmission Loss Factors (the “Loss Factor Rule”). A new loss factor methodology was implemented in the Loss Factor Rule effective January 1, 2017, reflecting decisions issued in Proceeding 790 of the Alberta Utilities Commission (“Commission”). The 2018 loss factors are provided here:

      In accordance with subsection 3(2) of the Loss Factor Rule, the AESO must provide additional information used to establish loss factors. This additional information is provided here:

      Anticipated losses on the transmission system are 2,248 GWh for 2018 and the average loss factor for the transmission system is 3.61% for 2018.

      In late 2017, the AESO consulted on revisions to the requirements for system topologies included in the Loss Factor Rule. To allow completion of the consultation process, the AESO requested and received forbearance from the Market Surveillance Administrator (MSA) in respect of any related non-compliance with the Loss Factor Rule. Please refer to the November 24, 2017 letter posted on the MSA website.

      The AESO encountered unanticipated complexity in preparing the 2016 energy market merit order data required for the 2018 loss factor calculations. The AESO accordingly requested further forbearance from the MSA in anticipation of publishing 2018 loss factors no later than the end of March, 2018.

      2018 calibration factors

      The calibration factor is a percentage adjustment that is added to or subtracted from every loss factor so that generating facilities and other services pay the actual (rather than forecast) cost of transmission losses. It applies to every loss factor for the system access services to which loss factors apply, in accordance with Rider E of the ISO tariffLosses Calibration Factor Rider.

    • 2016

      2016 loss factors

      Loss factors are used to determine the transmission losses charges that apply to system access service under the following rates of the ISO tariff:

      • Rate STS, Supply Transmission Service
      • Rate XOS, Export Opportunity Service
      • Rate IOS, Import Opportunity Service
      • Rate DOS, Demand Opportunity Service

      The Alberta Utilities Commission (the “Commission”) found the methodology currently used to calculate loss factors to be non-compliant with the Transmission Regulation. A new loss factor methodology is being determined through Commission Proceeding 790. The AESO will continue 2015 loss factors into 2016 on an interim basis, until loss factors based on a new approved methodology are implemented. The 2015 loss factors are provided here:

      2015 loss factors

      In accordance with section 32 of the Transmission Regulation, the AESO must make loss factors available to the public for a generating unit proposed to be constructed in Alberta. Updated information relating to the loss factors for some existing services may become available from time to time. The loss factors for the new services, as well as the updated information for existing services, are provided here:

      Loss factors for new services and updated loss factors for existing services

      For additional context, System Average Losses for 2016 have been estimated at 3.84%, compared to System Average Losses for 2015 of 3.66%.

      Note that the AESO has requested and received forbearance from the Market Surveillance Administrator (MSA) in respect of any related non-compliance with Section 501.10 of the ISO rules, Transmission Loss Factor Methodology and Requirements. Please refer to the November 6, 2015 letter posted on the MSA website.

      2016 calibration factors