The rapid development of computationally intensive AI applications is forcing data centre operators to fundamentally rethink their cooling strategy. With 463 exabytes of data predicted to be processed daily by 2025, conventional air cooling will no longer be sufficient - neither from an energy nor an economic perspective.
The answer to this is not a radical technological leap, but a targeted reorientation: modern cooling architectures combine direct-to-chip (DTC) cooling, precise airflow and immersion cooling to create a hybrid overall system. But how do these technologies differ - and what are their respective strengths, weaknesses and application limits?
This blog analyses the three leading cooling methods based on technical key figures, economic implications and practical application scenarios. The aim is to provide you with a reliable basis for your technology-neutral investments.
Direct-to-chip cooling has become the favoured solution for high-performance applications in recent years. The basic principle: dielectric coolant circulates in closed circuits directly above the heat-generating components - typically CPUs, GPUs or AI accelerators - and is dissipated via so-called cold plates. This arrangement maximises heat transfer locally at the hotspot and minimises energy losses in the overall system.
Key Benefits:
These advantages make DTC cooling the reference technology for all data centres that operate AI training, high-performance computing or other high-density workloads. The market is developing at a correspondingly dynamic pace: with a forecast compound annual growth rate (CAGR) of 20.5 per cent, the global DTC segment is set to grow to USD 11.89 billion by 2034.
One factor that should not be underestimated when implementing DTC systems is the choice of pipe material. The temperature and pressure requirements, combined with the need for absolute tightness and freedom from corrosion, make metallic pipe materials unsuitable. This is where the aquatherm blue pipe system offers the solution: the PP-RCT pipes are permanently leak-free, withstand dynamic pressure loads and are suitable for closed liquid circuits.
Despite the efficiency advantage of liquid-based systems, air cooling remains an indispensable element in the cooling architecture of modern data centres. However, its role has changed fundamentally: Away from the primary system - towards targeted supplementation for residual heat dissipation, infrastructure customisation and transition management.
Even with ideal implementation, direct-to-chip cooling can only eliminate around 70 to 75 per cent of the total heat load of a rack on average. The remaining 25 to 30 per cent is caused by thermal leakage, radiation to the environment or peripheral components outside the liquid circuits.
Even with ideal implementation, direct-to-chip cooling can only eliminate around 70 to 75 per cent of the total heat load of a rack on average. The remaining 25 to 30 per cent is caused by thermal leakage, radiation to the environment or peripheral components outside the liquid circuits.
Typical application scenarios for air cooling in hybrid environments:
Two developments are key here:
Wherever there are localised hotspots in the room - such as uncovered fixtures, power distribution boards or near walls - surface cooling can contribute to thermal equalisation. The aquatherm black surface heating and cooling system, originally designed for low-temperature surface heating systems, can also be used for reversible cooling: modular design, space-saving installation and constant temperature distribution. In retrofit projects in particular, this solution offers an opportunity to reduce the load on air systems on the room side.
Immersion cooling represents a paradigm shift: instead of dissipating the heat on component surfaces, servers are completely immersed in an electrically non-conductive cooling fluid. This process reduces the number of thermal transitions to a minimum and thus opens up efficiency reserves that even modern DTC systems can no longer achieve.
The target applications are clear: high-density workloads with GPU arrays of over 350 W per unit, especially in the field of AI training, machine learning and real-time inference. In such environments, the specific heat load per rack often exceeds 100 kW - a level at which conventional air or even DTC solutions reach their structural limits.
The technology is currently still considered a niche solution, but is growing dynamically:
The integration of immersion cooling places high demands on infrastructure and materials:
In the coming years, data centre cooling will evolve not through disruptive individual technologies, but through the systemic combination of specialised processes. The direction is clear: hybrid solutions - consisting of direct-to-chip, air cooling and immersion cooling - will become the standard for performance-orientated, scalable and sustainable IT infrastructures.
Three lines of development characterise this transformation:
Regulatory pressure as a catalyst for efficiency strategies
Government programmes such as the U.S. Department of Energy's ‘Coolerchips’ are defining new targets: in future, cooling energy should account for less than five per cent of the IT load - compared to double-digit proportions today. At the same time, certifications such as LEED, BREEAM or DGNB are gaining in importance - not only as proof of sustainability, but increasingly as an investment criterion for institutional investors. Against the backdrop of growing regulatory requirements, the focus is shifting not only to energy consumption and certifications, but also to the choice of materials. Our white paper on calculating the sustainability and costs of pipe projects shows why plastic pipes offer both ecological and economic benefits in the refrigeration technology sector.
Material technology as a prerequisite for system integration
The physical requirements of hybrid systems - particularly in terms of impermeability, chemical resistance, thermal stability and installation flexibility - are making traditional metal materials increasingly obsolete. The use of specialised polymer solutions, such as aquatherm blue, reduces hydraulic pressure losses, extends maintenance cycles and enables structurally integrated pipe routing while remaining completely corrosion-free. In addition, aquatherm black allows the subsequent integration of surface-coupled cooling surfaces - for example for the thermal decoupling of individual rooms or rack zones.
Systemic thinking replaces component-based planning
Future cooling strategies will no longer be technology-centred - but load-controlled, zone-based and interoperable. The combination of AI-supported monitoring, modular cooling circuits and material-specific infrastructure defines a new form of technical architecture: less as a technical subsystem and more as an energy-strategic backbone for data-driven business models.
Die Kühlung von Rechenzentren wird sich in den kommenden Jahren nicht durch disruptive Einzeltechnologien, sondern durch die systemische Kombination spezialisierter Verfahren weiterentwickeln. Die Richtung ist eindeutig: Hybridlösungen – bestehend aus Direct-to-Chip, Luftkühlung und Immersionskühlung – werden zum Standard für leistungsorientierte, skalierbare und nachhaltige IT-Infrastrukturen.
Modern data centers require layered cooling strategies: DTC for core heat removal, air systems for leakage control, and immersion for frontier AI workloads. This triad balances performance, sustainability, and cost, ensuring readiness for 463 exabytes/day data processing demands by 2025.
If you have any further questions, please do not hesitate to contact our experts. Together we will develop a solution that fits your IT strategy:
