REQUESTED ACTION

Information Only

SUMMARY

The California ISO posted a business requirements specification for its Energy Imbalance Market (EIM) Resource Sufficiency enhancements for market participant review. This document provides business requirements for changes to the EIM and Real-Time Markets that will implement in the spring of 2019.

MESSAGE

The ISO’s EIM Resource Sufficiency Enhancements policy initiative will provide independent evaluation for EIM Bid Range Capacity and Flexible Ramp Sufficiency Tests at a 15-minute interval granularity. This measure shall more-accurately account for load forecast variations within the trade hour, isolate flexible ramping insufficiency to the specific 15-minute interval that failed, and provide a tolerance bandwidth threshold for EIM balancing authority areas that minimally exceed their flexible ramping requirement (1% of the balancing authority area’s uncertainty requirement or 1 MW, whichever is greater). Specifics regarding implementation date(s) will be provided in Release User Group (RUG) communications. There will be no impacts to settlements.

Additionally, greater transparency will show for resource sufficiency test results in existing reports within the California ISO Market Results Interface (CMRI) and Open Access Same Time Information System (OASIS) systems. No modifications will be made to either system’s user display or Application Programmable Interface (API) technical specifications. Only the basis of the data results will change, specifically:

capacity test results will provide the most-insufficient 15-minute interval amount for the trade hour in both the “over” and “under” directions (instead of a single direction)
marginal sufficiency MW amounts will be provided for balancing, capacity, and flexible ramping sufficiency tests when passing (instead of the current default value of zero)
net EIM transfer limits will be provided for each 15-minute and 5-minute real-time market interval where the balancing authority area (BAA) transfer limits (both “high” and “low”) are frozen due to either 1) flexible ramping sufficiency test failure, or 2) occurrence of an ISO/EIM BAA contingency event

A business requirement specification (BRS) document describing the changes and providing examples of the new data basis for reported results will be posted at the following ISO website location: http://www.caiso.com/Documents/BusinessRequirementsSpecification_EnergyImbalanceMarketResourceSufficiencyEnhancements.pdf

Further documentation will be subsequently provided in the Energy Imbalance Market, Market Operations, and Market Instruments Business Process Manuals (BPMs).

CONTACT INFORMATION

For policy questions, please contact Megan Poage at mpoage@caiso.com. Non-policy requests may be directed to your Client Representative or ISO Customer Service at 916-608-7320.