BRIEF DESCRIPTION OF VENTILATION SYSTEM

1.0 Main Power House

Each 660 MW unit would be provided with 10 nos. of metallic construction (modular type) air washer units (AWUs) each of capacity 1,00,000 m3/hr. and 1 no. of metallic construction (modular type) air washer unit (AWU) of capacity 50,000 m3/hr. along with DIDW centrifugal fan with motor, pump with motor, instruments, piping and other accessories. These air washers shall be placed at various floors of TG building and shall supply cooled air to TG building by means of GSS/AL ducting, grills/ diffusers etc. Roof Extractors (RE) fans would be provided at roof of TG hall to exhaust hot air.

2.0 ESP Control room

To cater to the ventilation requirements of non- air conditioned areas (switchgear room, cable galleries, etc.) of ESP building, one (1) no. of Unitary Air Filtration (UAF) unit of capacity 75,000 m3/hr. would be provided along with DIDW centrifugal fan & motor, pump with motor, instruments, piping and other accessories for each unit of 660 MW. Cooled air shall be supplied to various non-AC areas by means of GSS/AI ducting, grills/diffusers for each unit.

3.0 Supply air fans/Exhaust air fans/ Roof extractor fans with drive motors shall be provided for miscellaneous areas such as pump house, MCC room, battery rooms, cable galleries, toilets, etc. in Main power house, Gas Insulated Switchyard (GIS) building and auxiliary buildings like CHP workshop, O&M workshop, compressor house, fuel oil pump house etc.

4.0 Ducts supplying air to switchgear rooms and cable spreader/ vault rooms in main power house and ESP building shall be provided with motor operated fire dampers. These dampers shall close in case of fire on receiving signals from the Fire Detection and Protection system.