Energy Efficient HVAC System for an IT park, Bangalore

• The project involves air-conditioning of Software and Hardware Park, Pritech 2 SEZ having an air-conditioned floor area of 12,48,620 sq.ft having three blocks namely blocks 5, 6 & 7. To cater to the air-conditioning needs a combination of water cooled centrifugal, air cooled screw and vapour absorption chillers are contemplated.

• 3 Nos Water cooled centrifugal chillers each having a capacity of 700 TR, 10 Nos air-cooled screw chillers each having a capacity of 350 TR and 1 no vapour absorption chiller using waste heat from Diesel Generating Set/Diesel/Compressed Natural gas totaling to a capacity of 6300 TR are envisaged. All chillers excepting the vapour absorption chillers are installed.

• The hybrid chiller combination with water cooled centrifugal chiller will use recycled water from Sewage Treatment plant and will run when the ambient is hot, the air-cooled screw chillers again with a combination of High and Normal Efficiency (5 nos of each type) will run during the periods of low/medium ambient temperatures while the vapour absorption chiller is mainly designed to run during the periods when DG sets are functional recovering the waste heat.

• This hybrid combination strike a perfect balance between energy efficiency and first and running costs. No standby chillers are envisaged owing to multiple chillers with multiple compressors. Further there is no separate critical chiller system (for 24/7 operating areas) as the same set of chillers can cater to the critical needs also thereby simplifying the chilled water distribution system.

• The chillers are located in the Utility block having the Lower level with DG sets, Middle level with pump sets and water cooled centrifugal and absorption chillers, intermediate level for chilled water and condenser water piping system and the upper level with air- cooled chillers and cooling towers.

• The Chiller platform is of RCC construction (compared to conventional metallic structure) free from piping system which has a longer life span with no rusting/ maintenance and lower first cost. The chiller power apportioning is using the state of the art ultrasonic BTU meters with software programming done to the exclusive need of the project. The BTU meters are protected from misuse/faulty operation by communicating the failure through mobile phones.

• The system is being hooked with the phase 2 system with another Chiller Plant room with a ring main concept making the system totally failure free and free from sabotage if any thereby offering the combined advantages of the central chilled water and individual chilled water system.

• Chilled water circulation is with primary and variable secondary pump sets with two way motorized valves for the Air-handling units. The system provides installation of air-handling units and air distribution system by the tenants.