Curtailment is the intentional reduction of power output when the grid cannot safely absorb all available generation. In energy systems, operators use it as a control measure to prevent overloads, congestion, or instability. It matters in cyber security because modern power grids depend on digital control systems, remote telemetry, and automated dispatch, all of which can be targeted or manipulated.
In a cyber attack, an adversary might falsify sensor data, disrupt forecasting, or tamper with control commands so operators believe the grid is more constrained than it really is, forcing unnecessary curtailment. The opposite risk also exists: hiding congestion until equipment is stressed. Defenders reduce these risks with authenticated telemetry, anomaly detection, segmented control networks, and manual fallback procedures. In practice, curtailment is not just an energy-market decision; it is a resilience issue for critical infrastructure.