Deferral Accounts - Rider C & DAR
Deferral Account Adjustment Rider (“Rider C”)
The ISO must recover or refund through Rider C accumulated deferral account balances, which are the difference between revenues and costs incurred in providing system access service to market participants.
Rider C is a charge or credit that the ISO determines each quarter by examining the available recorded and forecast values, required to restore the deferral account balance to zero (0) at the end of the calendar year.
- 2023 Rider C
- 2022 Rider C
2021 Rider C
- Q1 2021 Rider C Charge or Credit Calculations[Posted: November 30, 2020]
- Q2 2021 Rider C Charge or Credit Calculations - Revised[Posted: March 16, 2021]
- Q2 2021 Rider C Charge or Credit Calculations[Posted: February 26, 2021]
- Q3 2021 Rider C Charge or Credit Calculations[Posted: May 31, 2021]
- Q3 2021 Rider C Clarification[Posted: June 4, 2021]
- Q4 2021 Rider C Charge or Credit Calculations[Posted: August 31, 2021]
- Q4 2021 Rider C Clarification[Posted: September 3, 2021]
- 2020 Rider C
Deferral Account Reconciliation (“DAR”)
The DAR reconciles variances arising from the actual costs the ISO incurs in providing system access service and the actual revenue recovered through Rate DTS.
The ISO typically files the DAR with the Alberta Utilities Commission on an annual basis by the end of Q2 each year. Once the DAR is approved by the Alberta Utilities Commission, the ISO financially settles the deferral account balances with market participants, which typically occurs by the end of Q3 each year. To learn more about the DAR, register for the eLearning Course on DAR Methodology through the AESO’s Continuing Education site.
The 2022 DAR under proceeding 28293, was approved by the Alberta Utilities Commission in decision 28293-D01-2023. The 2022 DAR resulted in a $18.9 million surplus, that will be settled with market participants in September 2023.
The 2021 DAR under proceeding 27547, was approved by the Alberta Utilities Commission in decision 27547-D01-2022. The 2021 DAR resulted in a $9.5 million surplus, that was settled with market participants in September 2022.