A bidirectional substation is the control interface between a building and a district heating network that can work in both directions. It lets the building draw heat when needed and, in some designs, feed surplus heat back into the grid. The station typically combines sensors, valves, meters, heat exchangers, and control logic, so it is both a physical asset and an OT endpoint.
In cyber security, this matters because the substation sits where telemetry becomes action. If an attacker spoofs sensor readings, delays measurements, or alters control commands, the network may misjudge demand or accept heat at the wrong time, creating inefficiency or unsafe operating conditions. Defenders protect these systems with network segmentation, authenticated control channels, plausibility checks on measurements, and conservative fail-safe behavior. In practice, the best defense is to keep analytics and forecasting separate from core control and to ensure the substation can operate safely if data is missing or untrusted.