Description:

Inverter-Based Resources (IBRs), such as wind, solar, and battery storage, respond to grid fluctuations via programmed software controls rather than the physical momentum of traditional rotating generators. Because this technology is still maturing, the industry is actively learning how to integrate high volumes of IBRs on the distribution system without compromising reliability of the interconnected bulk power system. This challenge extends to large electronic loads like data centers, which also use inverters to connect to the grid and can destabilize the system if they unexpectedly disconnect during a disturbance.

The primary risk lies in modeling gaps—if the programmed behavior of these inverters is modeled incorrectly, planning assessments will fail to predict how the grid will actually perform under stress—and performance of IBRs during grid disturbances. When aggregated, these issues can lead to the sudden loss of power supply or demand, resulting in unstable and insecure grid operations. 

Key Drivers and Trends:

The primary driver of this risk is the fundamental shift in grid architecture as traditional power plants retire and are replaced by Inverter-Based Resources (IBRs). Unlike legacy generators, IBRs use high-speed electronic responses that are difficult to coordinate with slower physical systems, especially when multiple units are clustered together. While individual IBRs are small, their combined behavior can trigger large-scale reliability issues, a problem compounded by the fact that their settings can be changed remotely without a grid operator’s knowledge.

This risk is compounded by a knowledge gap within the industry. Because grid-scale inverter technology is still maturing, many developers and manufacturers lack deep familiarity with utility operations, leading to equipment that may not respond well to abnormal conditions. Furthermore, the industry currently lacks both the sophisticated power system models and the specialized expertise required to accurately predict and manage how these complex digital resources will behave during grid disturbances.

The figure below shows the breakdown of generation types within the MISO and SPP queues between 2025 and 2026. You can see a notable shift toward thermal resources (increasing from 5% to 17%) in 2026, while solar requests dropped significantly (from 46% to 30%) due to the sunsetting of federal tax incentives. Despite the recent rise in thermal generation (primarily natural gas), Inverter-Based Resources (wind, solar, and battery) still dominate 83% of the total queue, cementing their role as the primary future energy source for the region.

Event History

A North American Electric Reliability Corporation (NERC) report indicated in July 2024 that several large data centers disconnected from the grid following a disturbance that resulted in 1500 MW of load loss. The loss of load increased grid frequency and voltage, but not high enough to cause a reliability concern. Manual operation was needed to reduce system voltage within normal levels.

The Electric Reliability Council of Texas (ERCOT) experienced several events between 2023 and 2025 where large crypto-mining facilities disconnected from the grid following a disturbance. The loss of load have ranged between 100-450 MW. Causes of the disconnections varied, and none resulted in severe reliability impacts.

Since 2016, there have been 13 events involving the loss of IBR following a grid disturbance. The Blue Cut Fire disturbance was the first reported event in August 2016 and resulted in loss of 1,200 MW of IBR. NERC published actions and recommendations following this event, yet subsequent events occurred over the next six years.

In 2021 and 2022, there were two events near Odessa, Texas that resulted in a loss of 1,148 MWs and 1,711 MWs, respectively. Actions were taken by IBR owners after the first event to reduce the likelihood of recurrence, however, the second event resulted in a greater loss of MW output despite those actions.

Actions to Reduce Risk:

NERC is implementing a three-year FERC-approved work plan to identify and register bulk power system-connected IBR owners and operators. This is a three-year project that started in May 2023 and is scheduled to be completed in May 2026. The purpose of this initiative is to address a reliability gap associated with bulk power system-connected IBR resources that are currently not registered with NERC or required to comply with NERC standards

The following mandatory NERC Reliability Standards exist, or are under development, to help address this risk:

Other recommended actions include:

• Proactively mitigate performance challenges with IBRs by monitoring their response following grid disturbances and collaborate with IBR owners and operators to fix incorrect responses. Openly share identified issues and solutions so others can learn from these experiences.
• Follow industry recommendations in the Level 2 NERC Alert on development and use of models for IBRs in wide-area studies and interconnection-specific analyses. Additionally ensure inverter protection settings appropriately maximize availability of resources during and following a grid disturbance, while respecting inverter and substation equipment limitations.
• Seek information published by NERC’s Inverter-Based Resource Performance Subcommittee, which was formed in 2021 to focus on the reliable integration of IBRs into the bulk power system. In addition to the standards, the subcommittee has published reliability guidelines, white papers, event analysis, webinars, and gap analysis for IBR challenges not addressed by the NERC standards.