Holistic review of the resource sufficiency evaluation Stakeholders have requested a holistic review of the resource sufficiency evaluation. They state the EIM footprint has changed since the EIM implementation in 2014 and therefore the resource sufficiency evaluation approach should be evaluated. The ISO plans to complete a holistic review of the resource sufficiency evaluation during the extension of the day-ahead market to the EIM (EDAM), which is scheduled to start in the middle of 2019. Any EDAM design will require a day-ahead resource sufficiency evaluation. In order to introduce a day-ahead resource sufficiency evaluation, the ISO will need to align the day-ahead resource sufficiency evaluation with the real-time resource sufficiency evaluation. This is the appropriate time and place for a holistic review. Stakeholder Engagement The ISO has appreciated stakeholder engagement and comments during the April 30 and July 19, 2018 workshops. At this time the ISO is addressing items that were prioritized by stakeholders: freezing transfers for fifteen-minute intervals for failure of the flexible ramping test, introduction of a 1% tolerance band for the flexible ramping test, and a new approach to calculate the resource sufficiency evaluation requirement. None of these items require tariff changes and therefore can be implemented with the business practice manual (BPM) change process. Therefore, the ISO will not be pursuing a stakeholder initiative for the energy imbalance market resource sufficiency evaluation at this time. The ISO will discuss this paper during a stakeholder conference call on September 26, 2018. The ISO requests that any outstanding questions or comments are discussed at that time. Appendix A: Matrix from April 30 Meeting April 30, 2018 Energy Imbalance Market Technical Workshop
Training Questions and Comments Training Question/Comment ISO Response Entity Ensure the resource sufficiency test (RST) is equitably tested and enforced upon all EIM BAAs. The RST is applied equally to all BAAs that are participating in the EIM. BPA Chelan Portland Powerex WPTF The capacity test should be applied to all EIM entities in all hours. The capacity test is applied to all entities for all hours. Failing the capacity test results in the automatic failure of the flexible ramping test. The balancing test allows an EIM entity that elects to use the CAISO forecast to be exempt from the over/under scheduling penalty. If the ISO forecast is used and BAA’s imbalance (determined by comparing the BAA base schedules and the ISO’s demand forecast is within +/- 1%, the over/under scheduling penalty does not apply. If the EIM entity uses its own forecast, the over/under scheduling penalty applies. This is necessary because an entity could elect to submit base schedules as “long” or “short”. The over/under scheduling penalty does not apply to the ISO and will not apply to EDAM entities in the future because there is not an opportunity to determine the amount of imbalance to be met in the real-time market because base schedules are not submitted. The reference for imbalance settlement is the day-ahead schedule. Powerex Improve accuracy of resource sufficiency requirement to ensure there is no leaning on other EIM entities. The intent of the RST is to ensure each EIM BAA carries adequate capacity to maintain the balance between generation and load. This prevents one EIM entity from leaning on another. The ISO is planning to improve the calculation of the flexible ramping requirement. A proposed methodology has been discussed in the Day Ahead Market Enhancements (DAME) initiative. Chelan
tagged with a transmission profile by T-40; if a fifteen-minute dispatchable resource not, the schedule will be reduced to 0 MW and therefore does not count towards passing the RST. All EIM entities have imports/exports that are used in the determination of the requirement at T-40. These “hourly block” schedules must be tagged by T-20. This is the same for all EIM entities. Hourly blocked intertie schedules are considered in the historical non-delivery of imports/exports which increases the capacity requirement. The ISO will address the under-delivery of intertie resources in the Intertie Deviation Settlement initiative. RST should incorporate imbalance conformances that occur systematically in a particular direction. Imbalance conformances (aka “load biases”) can change by interval and are not guaranteed to be predictable. The ISO is addressing systematic conforming and making improvements to the conforming process as a result of the Imbalance Conformance Enhancements initiatives. Powerex RST should be measured relative to base schedules instead of the last interval of the previous hour. Using base schedules in the RST would result in inaccurate ramp capability. The balancing test does not ensure base schedules are ramp feasible between hours. For example, a participating resource schedule could be decremented during an hour and there would be no way to determine if it is ramp feasible for that resource to meet a dispatch for the next interval based on the base schedule. Powerex RST should be performed with granularity. This is not feasible. The RST results occur in the real-time unit commitment (RTUC) which occurs in 15-minute granularity. Puget Sound Energy Is the CAISO incorrectly receiving credits towards its flexibility capacity requirement? Double-counting of EIM Transfer credits is flawed No. There are no unique credits towards the flexibility capacity requirement. There is no double-counting in the FRST. The test recognizes that each BAA needs to Powerex