© Copyright 2009 Humidity Control Systems Ltd        Tel: 0044 (1) 522 753722 Dehumidifiers in Power Stations & Wind Turbines The preservation and longevity of power generation plant and stored machinery components is a significant problem, particularly in prolonged cold shut down situations. Power station protection and component preservation using the desiccant dehumidifier method is not new and has been used since the mid 60’s in the power industry as a barrier to moisture related degradation. Places in a power station where desiccant air dryers are recommended during shut down include:- Re-heater – tubes are thinner than superheater tubes and more susceptible to corrosion. Inter-granular attacks on austenic stainless steel can be minimised using dry air. Generator - it is important to keep the windings dry to prevent corrosion and ensure a shorter restart time. Dry air can also supplement generator heaters. Condenser – must be kept dry after flushing to allow re-coating of water boxes and tube plates. Feed & Condensate Pipes – important to eliminate internal corrosion on pipes as oxides can contaminate feed water. Reactor Vessel – Where access is required, dry air is required to purge out CO2, eliminate corrosion and to dry the graphite prior to refilling with CO2. Boiler – surface temperatures of fireside boiler tubing drop below the dewpoint and form condensate. The condensate reacts with sulphurous parts of the ash and acid deposits and hydrolyses, forming a highly acidic solution. The end result is rapid, localized attack of the metal surface.