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Feature these operations running 24 / 7 , particularly as more industries and governments shift to cloud computing , AI , and other dataintensive technologies .
In regions like South Africa , the construction of mega data centres is on the rise , but the benefits to the local economy can be unclear . While companies involved in the supply of highquality components — such as cooling systems , control valves and air handlers — stand to benefit , the majority of the design and manufacturing for large-scale data centres is outsourced overseas . This means that while local suppliers may gain contracts , the overall value added to the local market is limited .
ENERGY-SAVING SOLUTIONS FOR DATA CENTRES At a recent AERSA CPD points training session , Christian Preato , AERMEC ' s export area manager for African countries , shared valuable insights on energy-saving solutions specifically tailored for data centres .
“ Even if we are able to save 5-10 % of the electricity bill , over time it becomes a substantial sum .”
He noted that CIBSE / ASHRAE guidelines had introduced new allowable ranges for temperatures and humidity control within data centres - intended to remove obstacles to new cooling strategies . “ In the past 5-10 years the limits had been widened to higher temperatures of the return air to 30 ° C or even 35 ° C . The main advantage is that we can use routine procedures for the HVAC units on the computers within the data centres for many more hours during the day .”
He described three main types of data centre HVAC system , starting with ( though not necessarily the most efficient ) a chilled water system .
Chilled water system These are good for large capacity data centres to produce cooling at high EER ( energy efficiency ratio ), requiring low maintenance , minimised on the data centre floor with computer room air conditioning ( CRAC ) units . There are several energy saving opportunities including high water temperature production and external free cooling . The plant is centralised , using less refrigerant .
On the negative side , more time is required for engineering ( requiring greater expertise ) even a small data centre because a hydraulic system also needs to be designed as they require more infrastructure with water circulating in a data centre for instance needing leak control .
Direct expansion ( DX ) system Units are sized to match the load , thereby improving efficiency with new compressor technology and controllers . It permits easy installation of pipework due to a modular design and low cost . However , Preato notes that this system is impractical for large data centres ; has a potentially higher energy consumption especially at larger cooling capacities ; and is also affected by a need for leak detection and flammability of the eco-friendly refrigerants . “ It uses far more refrigerant , and it is inside the building .”
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Christian Preato , AERMEC ' s export area manager for African countries .
Image by AERMEC
AERSA ’ s NSM1602U - pompe blu – the new concept of designing a data centre .
www . refrigerationandaircon . co . za RACA Journal I January 2025 23