RACA Journal June 2023 | Page 37

Project

Efficiencies and reliability : There were some specific efficiency decisions that AMC took on this project to ensure optimal energy efficiency . Two of the most notable aspects were a reduced condensing temperature and a tight approach on the secondary PHEs . The condensing temperature was selected at 30 ° C , resulting in a 9K approach on the design ambient wet bulb condition . All condenser fans were equipped with VSDs to ensure fan law efficiencies were maximised during low load conditions , exponentially increasing efficiencies as load decreased .

The PHEs were selected with a very tight 2K approach resulting in a 4K LMTD for the HT and MT systems . What this further allowed is for the system to be able to operate with a PHE out of service by reducing the suction temperature by only 0.7K on the MT system and 2K on the HT system .

System reliability and redundancy is absolutely critical for this type of facility , considering the centralisation of the client ’ s distribution and the associated business and product value that moves through this facility . Redundancy was incorporated as responsibly as possible while ensuring that single points of failure were eliminated as far as possible . A further aspect that was implemented in the design is that where redundancy was required , it was employed to increase efficiency during normal operation , that is running the compressors at lower speeds for recips , running a reduced number of screws at full load on the MT system and reducing condensing temps and fan speeds on condensers . These energy savings elicit significant paybacks on the required redundancies and make the overall installation significantly efficient . RACA

LIST OF PROFESSIONALS : Owner Developer Architect / Designer Project manager

Consulting engineer

Contractors

Product suppliers