Meeting Summary - 03/14/2025 IBRWG Meeting

▶️1 - Antitrust Admonition

▶️2 - BESS Ride Through in WECC

BESS-Events-in-the-West.pdf

• Introduction by Curtis Holland about battery energy storage systems (BESS) in the Western Interconnection, covering parts of 14 states, 2 Canadian provinces, and Baja, Mexico.
• Overview of the role and technology of BESS, including their connection via inverters and operation through a battery management system.
• Statistics from the Energy Information Administration showing a significant increase in BESS capacity in California ISO and ERCOT.
• Different uses and capabilities of BESS, such as system peak shaving and regulation, with emphasis on California ISO's adjustments to ramp rates.
• Use case example of BESS during cold weather and its role during emergencies.
• NERC’s study on disturbances affecting BESS, highlighting systemic vulnerabilities in inverter-based resources.
• Detailed accounts of January 2024 cold weather event where BESS played a critical emergency role.
• Discussion on the impact of protective logic failures in BESS operations and implications during system events.
• Examples of unexpected BESS behaviors during grid events, highlighting the importance of correct control implementation and modeling.
• Issues with BESS causing oscillations in the system and proposed improvements such as hardware in the loop testing.
• Fire incidents associated with BESS and the challenges in extinguishing these fires, including significant ecological impacts and ongoing attention to these events.
• Closing remarks highlighting key resources for understanding BESS and addressing audience questions on lessons learned in PFR coordination and control strategy issues in BESS.
• Discussion around potential changes in interconnection requirements for BESS, specifically concerning hardware in the loop testing for identifying oscillations before integration.
• Julia Matevosyan and Fred Huang address a recent interaction with ERCOT battery owners regarding aggressive frequency response settings and the need to meet required droop settings to prevent excessive battery drain.

▶️3 - HRL of a single resource vs an aggregated value of a defined IRR Group

• Acciona Energy proposed allowing a single HRL value for grouped IRR units instead of individual HRLs to increase the stabilization of generation injection and reactive support.
• The current system evaluates compliance at the group level, but individual units are limited by their registered HSL or HRL.
• ERCOT Nodal Protocol Section 3.8.7 Self-Limiting Facilities, introduced recently with NPRR1026, may be relevant to the scenario.
• Self-limiting facilities are required to operate within agreed upon power limits at the POI.
• ERCOT is conducting internal discussions and plans to gather site-specific details to further evaluate the proposal.
• A follow-up meeting with Acciona representatives is planned to discuss site-specific details offline.
• Issues arise with solar plants having more units but being limited at the transformer level, affecting injection capacity.
• Acciona found similar plants in different regions with varying energy injection capabilities.

Future Actions:

• ERCOT to reach out to entities for site-specific details to potentially apply self-limiting protocol to IRR groups.
• Ismael Moral Díaz and Jose Villarreal from Acciona will coordinate with Abhi Masanna Gari from ERCOT for further offline discussions.
• Possibility of another meeting to discuss resolutions and share with the working group.

Additional Comments:

• Jose Villarreal from Acciona emphasized that the self-limiting facilities option may not fully resolve the issue.
• Acknowledged the opportunity to inject more energy from solar plants in the system.
• Acknowledgement of growing energy demand and the importance of optimizing solar energy injection.

▶️4 - Other Business

• A half-day workshop is scheduled for March 17 to discuss post-commissioning conformity assessment of inverter-based resource plans.
• The workshop will focus on assessing conformity with interconnection requirements and will be a hybrid event accessible online and in Austin.
• The event is sponsored by the DOE as part of the DOE I2X project targeting interconnection issues for generation resources.
• Announcement of the first grid-forming battery, Blackhillock battery storage, in Great Britain with 200 MVA capability.
• The battery is the first of five under construction due to the Stability Pathfinder tender.
• Results from an ESIG study on grid-forming batteries in the MISO system, particularly in ATC's weak and strong grid areas, have been published.
• A webinar was held discussing the study details, and a brief with results is now available.
• Suggestion for attendees to propose agenda items for the April meeting via email.

▶️5 - Adjourn