A nearly zero-energy cooling system is ready for commercial use.
Data powers everything from AI to streaming apps, relying on massive data centres that consume about 3% of the world’s energy. By 2028, their power demand could reach 130 gigawatts, equivalent to the output of 130 large nuclear plants. Did you know nearly 40% of this amount of energy is just for cooling? Improving cooling efficiency would bring significant benefits to both industry and the environment.
Data centres generate substantial heat due to densely packed servers and networking equipment. Efficient cooling is essential to prevent overheating, hardware failure, and downtime. Traditional cooling methods such as air conditioning and raised floor distribution are energy-intensive and costly, while others like evaporative cooling are climate-dependent.
Professor Wang Zuankai, Chair Professor of Nature-Inspired Engineering of the Department of Mechanical Engineering, has developed a better solution. His innovative Energy-Efficient Liquid Cooling System (ELCS) enables ultra-efficient, low-energy cooling for data centres and could play a major role in next-generation green data centre designs.
Overcoming a centuries-old challenge
ELCS is the result of Professor Wang’s efforts to tame the challenges posed by the Leidenfrost effect since 1756, where a vapour cushion beneath a water droplet on a hot surface reduces heat transfer. To address this, he developed Structured Thermal Armour (STA), a multi-textured material that disrupts the vapour layer, enabling more effective liquid-surface contact at high temperatures.
He has also engineered a hybrid surface combining superhydrophobic (water-repelling) and superwicking (water-attracting) properties. These microscopic structures use surface tension and capillarity to guide water droplets for rapid movement and evaporation. Superwicking zones draw water to hot areas for efficient cooling, while superhydrophobic regions control flow and prevent buildup. This design maximises droplet contact and evaporation, significantly improving heat transfer from hot components such as CPUs and GPUs.
ELCS leverages STA and the hybrid surface to maximise heat removal using liquids, maintaining efficient cooling even at very high temperatures. The system enables ultra-efficient evaporation and condensation cycles, with coolant drawn to hot spots, absorbing heat as it vaporises, then condensing back into liquid for reuse. This cycle uses minimal energy and handles much higher heat loads than traditional methods.
Advantages for data centre cooling
ELCS can reduce the need for energy-hungry air conditioning or liquid pumps, enabling faster and more effective cooling, higher server densities, and lower energy use. It uses less water than traditional evaporative cooling and is less prone to fouling or mineral buildup. Integrating AI and Intelligence-of-Things technologies, ELCS constantly monitors and optimises its own performance.
Furthermore, the system is scalable using advanced manufacturing techniques, making liquid cooling safer, more efficient, and sustainable. Data centres can operate at higher performance with less environmental impact.
From a cost perspective, the initial investment for ELCS is somewhat higher than conventional cooling methods. However, the return is transformative. According to Professor Wang, ELCS reduces cooling energy consumption by 40–50%, resulting in potential annual cost savings of up to HK$790,000 per rack.
Unleashing innovation to the market
With funding support from sources including the Innovation and Technology Commission of the HKSAR Government through the Research, Academic and Industry Sectors One-plus (RAISe+) Scheme, Professor Wang has founded LiquiCool Tech Limited, a PolyU academic-led startup, to commercialise the system.
“We have reached a significant milestone by validating ELCS’s core thermal performance in the lab,” Professor Wang said. “In Stage I of the RAISe+ Scheme, our focus is on system integration, durability, and customisation, with the goal of completing the prototype and initiating pilot deployments in Hong Kong. Stage II will deepen our presence in Hong Kong through partnerships and drive expansion into Mainland China and Southeast Asia.”
The scale and environment of Hong Kong and the Mainland provide an ideal foundation for advancing the technology and supporting the global transition to carbon neutrality.
To ease adoption, LiquiCool offers free installation and maintenance, charging only a share of verified energy savings—making energy efficiency and carbon neutrality accessible and risk-free for partners.
For individuals, this results in more affordable and accessible digital services, as operators pass on energy savings. Reduced energy consumption and lower carbon emissions also contribute to a cleaner environment.
“In essence, ELCS is not just about cooling servers but about cooling the planet, ensuring that the digital progress we all rely on—from streaming content to smart cities to AI innovations—can be powered without environmental cost, shaping a more sustainable and resilient future for society,” Professor Wang concluded.
