An offshore wind farm forms a closed power grid in the middle of the sea. In order to channel the energy generated by the individual wind turbines and feed it to the substation at sea, all the wind farm's turbines had to be interconnected by submarine cables. A total of almost 25 km of submarine cables of various power ratings were laid to transmit data and control the Riffgat turbines, all of which ultimately converge at the substation. An approximately 80 km long 155 kV link, known as the export route, ultimately transmits the generated power from the wind farm's substation to the Emden/Borkum substation on the mainland, from where the power is then fed into the German 220 kV grid.
The 6 km² offshore wind farm is located 15 km northwest of Borkum, Germany. It consists of 30 wind turbines. The 450-million-euro plant, which has a capacity of 108 MW, supplies around 120,000 households with climate-friendly energy. It is a joint project of the Oldenburg-based energy and telecommunications group EWE AG and the ENOVA group of companies.
All-round protection thanks to holistic fire protection solution
The wind farm substation is protected against fires all around by protection systems for early fire detection, fire prevention and fire extinguishing as well as the hazard management from the mainland.
The fire protection concept is based on TITANUS® aspirating smoke detectors for early fire detection. The aspirating smoke detection system is installed in various areas of the plant and continuously takes samples from the ambient air. These are analyzed for smoke particles. The system is highly sensitive, reacts up to 2,000 times earlier than conventional point detectors and is free of false alarms.
If the aspirating smoke detectors detect a fire, the FirExting® fire extinguishing system is used: the nitrogen stored in several extinguishing agent containers at the substation is flooded into the protected area. This is referred to as a rapid reduction in the oxygen level. Further oxygen supply is thus cut off and the fire is consequently smothered.
Since an extinguishing system can only extinguish fires over a certain period of time, the OxyReduct® fire prevention system is used after the rapid drawdown. Since the system extracts nitrogen from the ambient air itself on site using membrane technology, the low oxygen level in the protected area can be maintained for any length of time - even for days if necessary. Any remaining smoldering fire or re-ignition can thus be avoided.
To ensure that no incident at the manned substation goes unnoticed, all fire protection equipment is integrated into the VisuLAN® organization and hazard management system. All messages from the TITANUS® aspirating smoke detectors, such as info alarms, pre-alarms and the main alarm in dual-detector dependency, are recorded here and trigger specific actions defined in advance. In addition, the system documents all incidents related to the fire protection system. VisuLAN® thus also provides valuable information when processing a fire case.
Michael Kind, former Branch Manager North, WAGNER Deutschland GmbH
The fact that we can offer a wide range of products - from highly sensitive fire detection and gas extinguishing systems to fire prevention - combined with the associated decades of experience quickly convinced EWE and ENOVA.
