www . refrigerationandaircon . co . za RACA Journal I March 2024 11
Business
ADDRESSING COOLING SOLUTIONS Larger data centres require a lot more detail . Bester emphasises the importance of understanding the size of the data centre , the load it carries , and the specific needs of clients which may have stringent requirements . The choice between hot and cold aisle containment is influenced by factors like the building ' s layout and the placement of cooling equipment .
Bester notes that the ratio of data area to ancillary area is often 1:2 . Electrical components , especially in data centres with substantial loads , necessitate careful planning to accommodate generators , transformers and switchgear .
“ Some of these larger data centres require 3MW to 4MW electrical load and a single power source cannot accommodate that size of load . No single generator is that large to take the full duty load on this scale – so the centre has to be built with four or five energy sources , each supplying 1MW – 3MW with another backing it up : five or six transformers and UPSs , and more .
“ Power availability , stability and cost are key determinants , but a comprehensive site analysis is essential to ensure the data centre ' s long-term viability . The selection of a suitable site for a data centre extends beyond power stability considerations , as well as the cost of power . Specialised teams focused on site acquisition , evaluate factors such as fibre connections , telecom lines , flood risk , noise levels near residential areas , security , access to the site and risks , such as being in the flight path of aircraft landing at airports .”
Bester points to the often-overlooked aspect of noise management around data centres , which typically run 24 / 7 .
With massive generators and cooling equipment generating substantial noise , adherence to legislation becomes crucial . Acoustic consultants can be required to join the professional team , particularly in residential areas to ensure compliance with noise regulations , especially at night . The inclusion of acoustic louvres on acoustic lining on ducting and extending the exhausts on generators adds an extra layer of complexity and cost , he observes .
Bester underscores the importance of understanding connectivity issues and physical accessibility for installation and maintenance , emphasising the holistic approach required for successful site selection , quite irrespective of cooling issues . ASHRAE defines four groups of data centre equipment operating conditions namely A1 , A2 , A3 and A4 as shown in the psychrometric chart . The majority of data centres designed and operated in South Africa fall in the A1 group .
He describes the delicate balance of environmental control within data centres . “ With advancements in technology , the acceptable temperature range has widened , being 18 – 27 ° C air temperature supplied into a data centre and returning to the cooling units at 19 – 38 ° C , allowing for a more energy-efficient approach . With this wide temperature band , an acceptable temperature to supply air
www . refrigerationandaircon . co . za RACA Journal I March 2024 11