This rapidly increasing demand raises technical challenges in data centre cooling systems. And at the centre of the evolution is liquid cooling, a technology long understood but only now gaining traction in large-scale data centre environments. According to Leon Kleyn, Technical Director: Mechanical, WSP in Africa, and Floris van der Walt, Senior Mechanical Engineer, WSP in Africa, the rise of liquid cooling is both a response to market demand and a strategic opportunity for Africa’s growing digital ecosystem.

Why liquid cooling, and why now?

The sudden relevance of liquid cooling is a direct result of the explosion of AI workloads. Traditional computing relied on CPUs that processed tasks sequentially. AI, however, depends on GPUs 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 are capable of, in terms of performance,” explains Van der Walt. “Liquid has three to four times the cooling capacity of air, so it becomes the next viable option.”

Liquid cooling itself is not new, but the industry has historically not used it due to high costs, perceived risks and complexity. Now, rising heat loads have pushed technology providers and data centre operators towards solutions that can handle greater thermal heat rejection safely and efficiently.

Managing risks and technical complexity

The biggest concern is leakage – 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 cooling fluid’s quality. The systems use extremely fine cold-plate channels – down to microscopic dimensions – which are highly sensitive to contaminants. Minerals or impurities in potable water can block these channels, making ordinary water unsuitable.

Kleyn notes: “Liquid cooling systems typically use demineralised water, not just standard filtration.”

Beyond demineralisation, engineers must also prevent scaling and biological growth. This is 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.

Efficiency and environmental considerations

Liquid cooling offers clear efficiency advantages. “It is more efficient than normal cooling,” says Kleyn, noting that the engineered liquid rejects heat far more effectively than air, lowering energy use.

In water-scarce regions like South Africa, the question of water consumption and efficiency is unavoidable. “Liquid cooling does not mean significant water use,” Kleyn clarifies. “The system is a closed loop, filled once at commissioning and not using additional water during normal operation.”

“There shouldn’t be any water consumption,” Van der Walt stresses. “If you’ve got water consumption, it means you’ve got a leak.”

The fluid may eventually need treatment or replacement, though Kleyn confirms this happens infrequently and typically only alongside technology changes.

Opportunities and challenges for Africa

Africa’s climate, with high ambient temperatures in several regions, does not restrict the use of liquid cooling. These systems are more than capable of performing optimally under a variety of ambient temperatures. Instead, the challenges facing liquid cooling adoption on the continent lie in 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 ones. “Performance deviations must be detected and corrected immediately, and this requires specialised skills,” he explains. “On a positive note, this creates significant opportunities for upskilling Africa’s young workforce. But technical development for operations and maintenance staff is critical to ensure these systems operate optimally.”

Where liquid cooling fits in the African market

Liquid cooling is implemented only where needed. “Operators will try to use air cooling as much as possible,” says Kleyn. “Largely because of cost and complexity technical requirements. Demand for liquid cooling is driven by the adoption of GPU-based systems, particularly by AI-focused operators and global service providers expanding into African regions, to improve performance for local users.”

When an operator is ready to shift to GPU-based systems, Kleyn and Van der Walt confirm that liquid cooling can be implemented in both new and existing facilities. New builds are easier, but conversions are feasible. Industrial-type buildings with generous volumes and structural flexibility could also offer adoption of liquid cooled designs if there is sufficient power to the site.

As AI adoption accelerates across the continent, liquid cooling will increasingly shape the next generation of data centres in Africa. While the technology introduces new layers of complexity, it also offers significant efficiency gains and positions operators to meet the rising demands of a digital, interconnected and latency-sensitive marketplace.

“It yields significant benefits for operators, the environment and the end user,” Van der Walt confirms. As liquid cooling rapidly shifts from emerging trend to strategic necessity, operators of both legacy infrastructure and new builds across the continent will have to adapt.

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Leon Kleyn  - WSP in Africa

Floris van der Walt - WSP in Africa