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Liquid cooling in African data centres – a turning point in design As artificial intelligence becomes more deeply embedded in how organisations operate, the infrastructure to support these digital tools is undergoing a major shi. Data centre capacity needs to increase rapidly to power AI processes. And this raises technical challenges in data centre cooling systems. Leon Kleyn, Technical Director: Mechanical, and Floris van der Walt, Senior Mechanical Engineer, at WSP in Africa, look at the rise of liquid cooling – as a response to market demand and an opportunity for Africa’s growing digital ecosystem.
T he African data centre market is growing quickly: research places estimated market value at USD 1.94 billion in 2025 and it is expected to reach USD 3.85 billion by 2030 [1] . The fast increasing demand for high density computing data centres is driving the evolution of cooling systems, seeing liquid cooling assume a central role. Liquid cooling is a technology long understood but only now gaining traction in large-scale data centre environments.
Kleyn notes: “Liquid cooling systems typically use demineralised water, rather than standard filtration.” Beyond demineralisation, engineers also need to prevent scaling and biological growth. This can be achieved by introducing a propylene glycol mixture that stabilises the fluid and inhibits biofilm formation. As van der Walt puts it, fluid treatment forms “a whole new industry on its own”, requiring collaboration between water-treatment specialists, cooling-system manufacturers, and engineers. E iciency and environmental considerations Liquid cooling o ers clear e iciency advantages. “It is more e icient than normal air cooling,” says Kleyn, explaining that the engineered liquid rejects heat more e ectively than air, lowering the system’s energy use. In water-scarce regions like South Africa, the issue of water consumption and e icient usage is a primary concern. “Liquid cooling does not mean significant water use,” Kleyn clarifies. “The system is a closed loop, filled once at commissioning and not requiring additional water during normal operation.” “There shouldn’t be any water consumption in a liquid cooling system,” van der Walt emphasises. “If the data centre registers high water consumption, it means there’s a leak.” The fluid may over time need re-treatment or replacement, although Kleyn confirms this happens infrequently and usually only with technology changes. Opportunities and challenges for Africa Africa’s climate, with high ambient temperatures in most regions, does not restrict the use of liquid cooling. The systems are more than capable of performing optimally under various ambient temperatures. The main challenges facing the adoption of liquid cooling on the continent relate to manufacturing capacity, supply chains and specialised skills. Because Africa does not manufacture coolant distribution units (CDUs) locally, operators fall into global supply queues. This can lead to project delays as larger international projects take precedence in supply chains. In addition, van der Walt notes that liquid-cooled systems are not as forgiving as air-cooled systems. Performance deviations need to be detected and corrected immediately, and this requires specialised skills. On a positive note, this creates significant opportunities for upskilling Africa’s young workforce. Technical development for operations and maintenance sta is critical to ensure the systems operate optimally.” Kleyn says liquid cooling is implemented only where needed.
Why liquid cooling, now? The current relevance of liquid cooling is a direct result of the explosion of AI workloads. Traditional computing relied on CPUs (central processing units) that processed tasks sequentially. AI, however, depends on GPUs (graphic processing units) that process multiple tasks in parallel, which significantly increases energy use and, in turn, heat generation. “We are reaching the limit of what traditional air- cooling systems can do, in terms of performance,” says van der Walt. “Liquid cooling provides three to four times the cooling capacity of air, so it becomes the next viable option.” Although liquid cooling is not new, it has historically not been used due to its relatively high costs, perceived risks and complexity. Now, rising heat loads have pushed technology providers and data centre operators towards solutions that can handle greater heat rejection safely and e iciently. Managing risks and technical complexity The biggest concern is leakage – the risk of liquid coming into contact with expensive electronic equipment. “Leaks are one of the biggest risks,” says van der Walt. “You need strategies to detect and mitigate them.” Another challenge lies in protecting the quality of the cooling fluid. The cooling systems use extremely fine cold- plate channels – at microscopic dimensions – which are highly sensitive to contaminants. Minerals or impurities in potable water can block the channels, which makes ordinary water unsuitable for use in these systems.
From Top: Leon Kleyn and Floris van der Walt of WSP in Africa.
6 Electricity + Control MARCH 2026
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