The Department of Energy’s Office of Cybersecurity, Energy Security, and Emergency Response brought utilities, industry experts, and government defenders together on Plum Island, New York, for the annual Liberty Eclipse exercise, a full-scale cyber training event designed to strengthen U.S. energy grid resilience. Using an isolated 840-acre grid that mirrors real utility environments, participants from power companies, national laboratories, and partner organizations tested their ability to detect, respond to, and recover from a range of simulated cyberattacks, from noisy intrusions and ransomware to stealthy, engineered compromise scenarios.