Updates to Performance Requirements: Market Rule Appendices 4.2 and 4.3

Like most other jurisdictions in North America, Ontario has a long history of transmission-connected generation facilities producing electricity and supporting grid reliability. With increased penetration levels of distributed energy resources (DERs), that picture is changing. Complicating matters is the fact that existing Market Rules in Ontario have no specific performance requirements for DERs or load displacement units (LDUs) units with an installed capacity less than 10 MW, or facilities with total aggregate generation of less than 50 MW.

In practical terms, that means these generation units may connect to the electricity system without having the ability to provide the necessary support for reliability, in particular, following transmission system disturbances. The IESO’s 2019 Operability Assessment identified potential concerns related to increased penetration of DERs and made recommendations to improve the performance of DERs to support reliability during and immediately following specific transmission system disturbances. The assessment also showed a need to clarify performance requirements for inverter-based generation units, as existing requirements are tailored for conventional generators.  Inverter-based generators behave differently than conventional generators, as highlighted in the NERC industry recommendations and event analysis reports following the system disturbances in California.

The IESO proposes to update Appendices 4.2 and 4.3 to improve the performance of DERs and mitigate the concerns identified in the Operability Assessment, to clarify the performance requirements for inverter-based resources, and to ensure the IESO Market Rules are consistent with the newly released NERC PRC-024-3 and CSA 22.3 no.9 standards. The proposed changes are also intended to align the performance requirements with on-site validation testing processes and requirements. The IESO is seeking feedback from stakeholders on these proposed updates to the performance requirements in Market Rule Appendices 4.2 and 4.3. All comments and enquiries on this engagement can be directed to engagement@ieso.ca.

Related NERC Studies

Industry Recommendation Loss of Solar Resources during Transmission Disturbances due to Inverter Settings

Industry Recommendation Loss of Solar Resources during Transmission Disturbances due to Inverter Settings - II

1,200 MW Fault Induced Solar Photovoltaic Resource Interruption Disturbance Report

900 MW Fault Induced Solar Photovoltaic Resource Interruption Disturbance Report

Schedule of Activities