Data centre cooling: the industrial challenge redefining the refrigeration sector
Artificial intelligence has changed the thermal demands of data centres for good. What used to be solved with industrial air conditioning now calls for liquid cooling, precision hydraulic design and high-availability maintenance.
Refrigeration engineer - Isofred
Artificial intelligence has turned a great many things upside down. One of the least visible, but with the most practical consequences, is what is happening in machine rooms: data centres today consume around 1% of the world’s electricity and, according to various industry projections, that figure could approach 8% by 2030.
Behind that leap lies a fundamentally thermal problem, and solving it well requires exactly what companies like Isofred have been doing for decades: designing, installing and maintaining bespoke industrial refrigeration systems.
The problem: more heat per square metre than ever
Ten years ago, a standard rack in a data centre generated between 5 and 10 kW of heat. Today, artificial intelligence and high-performance computing (HPC) servers can exceed 60-150 kW per rack. That leap in thermal density changes everything.
Air-based cooling systems (the CRAC and CRAH units that have been the workhorse of data centres for decades) start falling short once density exceeds 20-30 kW per rack. Airflow distribution becomes unpredictable, hot spots multiply and the energy needed for cooling grows out of all proportion.
Key industry indicator
PUE (Power Usage Effectiveness) measures a data centre’s efficiency: a value close to 1.0 means all the energy goes to computing. A data centre with oversized or poorly designed cooling can exceed 1.5 or 2.0, meaning that for every kilowatt of compute, as much again is spent on cooling.
The industry’s answer: liquid cooling
The clearest trend of the past two years is the transition, in full or in part, to liquid cooling. Industry studies estimate this technology can cut the energy consumed by cooling by 30 to 40% compared with traditional air systems, with significantly greater thermal stability.
Two main approaches are gaining ground:
1. Direct Liquid Cooling (DLC)
The coolant circulates through cold plates fitted directly onto the CPUs, GPUs and accelerators. It is currently the most widely deployed solution in new builds and in retrofits of existing data centres.
It allows operation with higher liquid outlet temperatures, which opens the door to reusing that waste heat for other purposes (building heating, industrial processes, etc.).
2. Immersion cooling
Servers are submerged directly in a dielectric fluid. Heat removal is practically uniform and dependence on airflow drops to zero.
Companies such as Submer, headquartered in Barcelona and with a 56 MW data centre project under way in the city, are proving that this technology can cut water consumption to virtually zero and support more than 150 kW per rack or tank.
The role of HVAC: more critical, not less
One might think liquid cooling makes HVAC dispensable. The reality is the opposite: air conditioning systems remain essential, but their design and sizing become more demanding.
In a modern data centre, the HVAC has to:
- Manage the heat the liquid extracts from the racks and transfer it outdoors via cooling towers, condensers or heat exchangers.
- Maintain ambient conditions (temperature, relative humidity) within the ranges ASHRAE requires for the IT room.
- Integrate free cooling strategies, using outdoor air whenever the ambient temperature allows, to cut compressor consumption.
- Guarantee the redundancy and uptime a critical infrastructure demands, so that a cooling system failure never compromises availability.
Key difference
In a data centre there is no scheduled downtime for maintenance. The design must provide N+1 or 2N redundancy in critical equipment, and preventive maintenance becomes a differentiating factor that leaves no room for improvisation.
Trends in Spain: from theory to construction
The Spanish market is no stranger to this movement. Around Madrid and Barcelona, the first commercial deployments of liquid cooling at industrial scale are taking shape. European regulatory pressure on sustainability (the energy efficiency directive, the F-Gas Regulation, the ESG requirements of major operators) is accelerating the conversion of existing infrastructure.
+$21,000M
Global data centre cooling market in 2026
12.6%
Annual growth rate of the sector
60 kW
Power per rack in the first DLC installations in Spain
Hybrid solutions, combining air for low densities and liquid for high-density racks, are becoming the de facto standard for new builds and modernisations.
What this means for specialist installers
The rise of data centres as an industrial client opens up a demanding but very attractive segment for companies with industrial refrigeration and HVAC capabilities.
Greater technical complexity
A data centre cooling project is not just about installing split units or a refrigeration machine room. It involves designing precision hydraulic systems, managing dielectric fluids, integrating with BMS (Building Management Systems) and complying with IT-sector-specific standards.
Continuous maintenance
The criticality of these facilities makes preventive and corrective maintenance contracts the norm, not the exception. This fits directly with Isofred’s service structure, which works with RITE and comprehensive maintenance contracts in equally demanding sectors (pharmaceuticals, agri-food, temperature-controlled logistics).
Integration with IoT monitoring
Major operators demand real-time supervision systems (temperature, humidity, flow rate, energy efficiency) integrated with management platforms. The ability to provide this monitoring layer is an increasingly differentiating factor.
Conclusion
Data centre cooling is, in essence, a high-stakes refrigeration engineering problem. The thermal density of today’s workloads is forcing a technological shift that requires liquid solutions, bespoke installation design and high-availability maintenance.
For companies experienced in complex industrial refrigeration installations (ripening rooms, cleanrooms, pharmaceutical cold chains), data centres are a natural segment to grow into. The technical foundations are the same; the operational demands, just as high.
Facing a data centre cooling project?
At Isofred we have spent more than 25 years designing and delivering industrial refrigeration installations in critical sectors. If you are looking for a technical partner with maintenance capability in Catalonia and along the Mediterranean arc, get in touch.
