RACA Journal April 2023 | Page 39

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Project

Development at the R4-billion mixed-use Oceans Mall has reached a critical phase allowing it to open to the public . Two of the proposed three phases are complete with the five-star Radisson Blu and Oceans Mall open to the public . The third phase is made up of two residential towers with +/ - 500 residential apartments . The mall comprises of a world-class shopping mall with over 100 stores .

Two of Africa ’ s largest state-of-the-art retailers anchor the mall , while it also promises to offer a variety of speciality stores and including international superbrands , such as Burberry , Versace , Armani and Paul & Shark . Apart from retail , the mall will provide a range of leisure and entertainment activities such as Fit 24 ( 24-hour gym ), and 20 world class restaurants .
The project initially commenced in 2015 with the first phase of construction beginning in 2018 with the Hotel . The project was then put into a sleep period for various reasons , starting up again towards the latter part of 2020 . When the Hotel was midway through , work began on phase 2 – the Oceans Mall . The Hotel was completed in October 2021 and the Mall in November 2022 .
The design brief was to design a central chilled water plant similar to that of a district cooling plant that would service the various buildings as part of the development . This required multiple chillers , each with standby and duty pumps sets . Efficiency and space requirements played a major role in the selection of the chilled water system . Being less than a kilometre from the shoreline , a water-cooled chilled water system was selected for its efficiency and longevity as there are less components exposed to the elements when compared to aircooled systems .
MAINTENANCE COSTS REDUCED The central chilled water system was the system-of-choice based on lowest overall energy consumption , lower maintenance costs and most economical plant space requirements . The same type of system is used extensively for mixed use developments in Dubai . The use of a central system allows better provision for redundancy without duplication in numerous separate systems . It also allows better use of diversity which is substantial in a mixeduse development .
The system provides a long lifespan , in the region of 25 to 30 years with proper maintenance . Overall maintenance costs are reduced as there are fewer moving parts when compared to air cooled alternatives .
The bulk of the power supply is centralised , which is more cost effective and economical . The challenge of recovering energy usage and maintenance is achieved by the installation of energy meters for all users as follows :
• Hotel at main supply
• Residential at each apartment
• Retail at each zone Air Handling Unit
All photos by RPP KZN Consulting Engineers
Centrifugal chillers at the Oceans Mall .
Gym spiral ducting and smoke extraction fans .
The energy meters accurately measure chilled water flow and temperature to summate kW cooling , allowing apportionment of running and maintenance costs according to actual usage . Each of these meters transmit the readings to the central BMS / Billing System to be provided by the electronics engineer .
AIR CONDITIONING – CENTRAL PLANT The installation consists of a centralised water-cooled chilled water system with multiple chillers consisting of a mix of base load high efficiency centrifugal chillers and intermediate step load high efficiency screw chillers . The chillers together with the Chilled Water and Condenser Water Pumps are positioned in an enclosed plant room on Level 4 of the development .
The chillers are served by a number of open-circuit cooling towers which are mounted in an open plant area situated at the back of the site so as to avoid noise pollution to the Hotel and residential blocks .
Each chiller is interconnected with one or more cooling towers by means of galvanised steel condenser water piping and condenser water pumps including standby pumps . Chilled water is circulated to each building by means of insulated medium black steel ring main piping and chilled water pumps including standby pumps . At various plantrooms , there is a dedicated heat exchanger and a tertiary chilled water pump

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