GridEx VIII puts Great River Energy to the test

National grid exercise simulates wildfires, ice storms and sabotage

Practice makes perfect. That was the mantra last month at Great River Energy as the two-day GridEx VIII crisis exercise simulated several emergencies, including a substation fire, cybersecurity breach, wildfire, winter storm and widespread power outage. 

GridEx, the electricity industry’s largest cyber and physical security exercise, is hosted every two years by the Electricity Information Sharing and Analysis Center (E-ISAC). It provides industry and government partners the opportunity to practice in real time how they would respond to — and recover from — coordinated security threats to the grid.

“The crisis exercise reached just about every corner of the company and tested several business-critical response plans. It was remarkable to watch everyone jump to action to protect our system and serve our member-owners.” 

— Walt Ullrich, control center support supervising manager who led the team tasked with creating and facilitating the crisis exercise at Great River Energy.

The crisis exercise began with a simulated act of vandalism quickly followed by reports of a wildfire threatening transmission corridors.

Meanwhile, IT responders were busy reacting to a simulated cloud provider outage and a coordinated cyberattack that coursed through the cooperative’s network infrastructure. 

Throughout the two-day exercise, a team of crisis commanders held regular calls with liaison teams representing various areas of the company, from cyber and physical security to finance and human resources, to foster collaboration and communication.

As the crisis exercise grew and evolved, teams across Great River Energy acted quickly to determine the most prudent solutions to handle the simulated events. The cooperative’s security operations center also remained engaged to coordinate responses by employees and local authorities.

According to E-ISAC, participation in the 2025 exercise increased by 48% from the last time it was held in 2023, with more than 370 organizations simultaneously running through their emergency preparedness plans and protocols.

The national exercise concluded with a tabletop session that brought together industry and government executives to focus on strategic and policy-level issues raised during the event. A public report on GridEx VIII will be released by E-ISAC in the first quarter of 2026.