Revisions to Tariff for Reactive Capability Audits of Electric Storage Facilities and Non-Generator Dynamic Resources

1. February 12, 2019 | Westborough, ma Kory Haag (413) 535-4064 | khaag@iso-ne.com Revisions to Section III.1.5.3 of the Tariff, OP-23, and OP-23 Appendix G (OP-23G) to include Electric Storage Facility and Non-Generator Reactive Resource Auditing Reactive Capability Audit Revisions Revision 1

2. In October 2018, the ISO, joined by NEPOOL, filed with FERC proposed revisions to the ISO-NE Open Access Transmission Tariff which created multiple constructs for storage devices to fully participate in the ISO Day-Ahead and Real-Time Energy Markets • Currently awaiting a FERC Order on the proposed revisions (Docket No.ER19-84-000) • In addition to the implementation of the constructs for storage devices, in recent years other non-generator dynamic Reactive Resources (e.g. synchronous condensers, SVCs, STATCOMS) have been proposed or constructed • The reactive capability of a storage device or non-generator Reactive Resource can, similar to a Generator Asset, directly affect operating limits • This creates the need for revisions to the Reactive Capability Audit provisions in the Tariff and Operating Procedures

3. This presentation provides (i) a summary of current provisions and (ii) an overview of the upcoming proposed revisions that are needed in the Tariff and Operating Procedures in order to: • Extend the reactive capability auditing requirements to non-generator dynamic Reactive Resources and Electric Storage Facilities (ESFs); and, • Specify the Reactive Capability Audit processes associated with Electric Storage Facilities (ESFs) • Related revisions to the ISO New England Ancillary Service Schedule No. 2 Business Procedure in order to accommodate the introduction of ESFs will be discussed at the Transmission Committee starting on February 20, 2019

4. Background

5. Summary of Current Provisions in the Tariff and OP-23 Related to Reactive Capability Audits • Under Section III.1.5.3 of the Tariff, ISO may require Reactive Capability Audits from Generator Assets that affect reliability • Leading and lagging audits required (unless one mode exempted) • OP-23 Resource Auditing contains provisions for Reactive Capability Audits: • Current provisions provide for Reactive Capability Audits of: • Generator Assets • Storage Resource is currently treated as a traditional Generator Asset with no Reactive Capability Audits for the associated DARD • Non-generator Reactive Resources • List of resources required to perform Reactive Capability Audits under Section III.1.5.3 of the Tariff is contained in OP-23G

6. Proposed Revisions associated with ESF and Non-Generator Dynamic Resources

7. Summary of Proposed Changes for Reactive Capability Audits of Both ESF and Non-Generator Reactive Resources • Section III.1.5.3 of the Tariff: • Extend provisions to include Reactive Capability Audits for ESF DARDs and non-generator Reactive Resources: • OP-23 changes require Reactive Capability Audits for Reactive Resources that meet certain criteria: • Individual equipment that is (i) greater than 20MVA, (ii) directly connected to 100kV and above, and (iii) not exempted from voltage control; or, • Resources that ISO and the LCC determine directly affect operating limits or local area voltage limits • Add ESF and non-generator Reactive Resources that meet Reactive Capability Audit criteria to list of resources required to perform Reactive Capability Audits in OP-23G

8. Additional Proposed Revisions associated with ESF Dynamic Resources

9. Overview of Electric Storage Facilities • Two types of ESFs: Binary and Continuous • Binary Storage Facilities require time to transition between consuming and producing energy • Continuous Storage Facilities can transition from full consumption to full production of energy (or vice versa) within 10 minutes • Electric Storage Facilities will be modeled as one of the following: • Binary: Generator Asset and Dispatchable Asset Related Demand (DARD) • Continuous: Generator Asset, DARD, and Alternative Technology Regulation Resource

10. Summary of Proposed OP-23 Changes for Reactive Capability Audits of Binary Storage Facilities Binary Storage Facility Generator Assets: • No change to Reactive Capability Audit process Binary Storage Facility DARDs: • Lagging and leading audits • One hour duration • Performed at maximum consumption capability at the time of the audit

11. Summary of Proposed OP-23 Changes for Reactive Capability Audits of Continuous Storage Facilities Generator Assets • Lagging Reactive Capability Audit • Real Power output: within 5% or 2MW (whichever is greater) of 90% of summer Network Resource Capability (NRC) • Audit duration: If the resource can operate at full MW output for 60 minutes, then the audit will be for 60 minutes; if not, then the audit will be for the maximum production time at the required MW output given that, at the start of audit, the resource is at its maximum available energy • Duration Example 1: Battery with 4 MWh of capacity and 2 MW inverter capability. Audit Duration is 1 Hour because Asset can produce at 2 MW for 2 hours when full. • Duration Example 2: Battery with 2 MWh of capacity and 4 MW inverter capability. Audit duration is 30 minutes because Asset can produce at 4 MW for 0.5 hours when full. • Leading Reactive Capability Audit • Real Power output: neither consuming nor producing power during the audit (taking into account losses) • One hour duration

12. Summary of Proposed OP-23 Changes for Reactive Capability Audits of Continuous Storage Facilities (cont.) DARDs • Lagging and leading audit • Real Power consumption: within 5% or 2 MW (whichever is greater) of 90% of the Generator Asset summer NRC value (applied in the consuming direction) • Audit duration: If the resource can operate at full MW consumption for 60 minutes, then the audit will be for 60 minutes; if not, then the audit will be for the maximum consumption time at the required MW output given that, at the start of audit, the resource is at its minimum available energy • Duration Example 1: Battery with 4 MWh of capacity and 2 MW inverter capability. Audit Duration is 1 Hour because Asset can consume at 2 MW for 2 hours when empty • Duration Example 2: Battery with 2 MWh of capacity and 4 MW inverter capability. Audit duration is 30 minutes because Asset can consume at 4 MW for 0.5 hours when empty

13. Example Auditing Points for Continuous Storage Facilities Revision 1

14. Summary of Proposed Revisions

15. Conclusion The proposed changes to the Tariff and OP-23 • Provide Reactive Capability Audit data from non-generator and Electric Storage Facility resources that affect operating limits • Provide specific procedures for Electric Storage Facility Reactive Capability Audits

16. Stakeholder Schedule

17. Kory Haag 413) 535-4064 | khaag@iso-ne.com