Adjustment to intertie constraint penalty prices

Started: Nov 12, 2021

During the 2021 summer months, when system conditions were more constrained than other times of the year, the ISO identified instances where market schedules exceeded the de-rated limitations of certain interties in the Real-Time Market (RTM), due to transmission outages caused by wildfires, and because of the interplay of scheduling priorities within the ISO's market optimization. The ISO also identified such overscheduling on the interties within its Residual Unit Commitment (RUC) process. This overscheduling results in an overestimation of RTM capacity actually available. To resolve this inconsistency between market results and actual conditions, the ISO must manually curtail schedules to ensure flows are within operating limits. This initiative identifies the reasons why market overscheduling occurred, and proposes changes to specific penalty price parameters to ensure the market is able to resolve similar situations in the future, consistent with actual physical conditions on the grid.


Proposal Development Decision Implementation Completed/Closed
Jan 21, 2022 Draft final proposal posted
Feb 09, 2022 Joint ISO Board of Governors and WEIM Governing Body approval
Jun 01, 2022 Activation
Implementation milestones