Capacity Auction

The IESO's Capacity Auction has replaced the former Demand Response Auction to enable competition between additional resource types. Capacity auctions help meet Ontario’s reliability needs in a cost effective manner while allowing the IESO to transparently adjust to changing system needs.

The IESO held Capacity Auction #1 on Wednesday, December 2, 2020 for the 2021 Summer obligation period.

For further details on the stakeholder engagement meetings and process that enabled the transition to a Capacity Auction, please refer to the Capacity Auction engagement page.

What do I need to do to participate in Capacity Auction?

Interested organizations must become authorized as a Capacity Auction Participant (CAP). This process must be completed at least 40 business days before the start of the offer submission window of an auction. The CAP authorization process is a one-time process, meaning a CAP will be then able to participate in all subsequent auctions. Following authorization, a CAP will then complete the capacity enrollment process and submit auction deposit in order to participate in the Capacity Auction. A capacity enrollment request can be modified up until the last day to submit a request, at which point, modification is locked in Online IESO.

What happens before the Capacity Auction?

The Pre-Auction period begins approximately two months prior to the start of the offer submission window for the Capacity Auction, when the IESO publishes the Pre-Auction Report.

The Pre-Auction Report includes the following information for each commitment period:

  • Key Milestone Dates, including submission of capacity enrollment information, payment of auction deposit, and date of auction
  • Auction Parameters, including Target Capacity, Maximum and Minimum Clearing Prices, Capacity Limits, and;
  • Zonal/ Import/ Interface Constraints.

The Pre-Auction Report for Capacity Auction #1 is available on the IESO Public Reports site.

What happens during the Capacity Auction?

Following the auction submission period, the IESO processes all capacity auction offers, determines clearing prices and quantities. The results are published 5 business days after the auction submission period in the Post-Auction Report which includes the following information for each obligation period:

  • Capacity Auction clearing price;
  • Amount of MW cleared for each electrical zone;
  • List of successful CAPs and their capacity obligations; and
  • Enrolled auction capacity, by participant

The  Post-Auction Report for Capacity Auction #1 is available on the IESO Public Reports site.

What happens post Capacity Auction?

Following the auction, a successful participant will be required to become authorized as a Capacity Market Participant. The authorization allows a participant that clears the auction to receive availability payments, subject to non-performance charges, and to satisfy their Capacity Obligation(s). Payments are based on the total cleared capacity and the applicable auction clearing price.

Demand Response Auction

For information relating to the former Demand Response Auction, including Pre-Auction Reports, Post-Auction Reports and other related documents visit the Demand Response Auction webpage.