Data centres are becoming critical infrastructure for healthcare, energy, transport and everyday digital services. Their electricity use is rising fast—driven in particular by artificial intelligence and high-performance computing. Almost all electricity consumed by servers is ultimately converted into heat, which must be removed to ensure reliable operation, and cooling itself can account for a significant share of a data centre’s total power demand. CoolHeatDC develops a new integrated heating-and-cooling solution that enables climate-friendly cooling for hyperscale data centres and makes it easier to recover and upgrade excess heat for use in district heating and industrial heating.
Why this project
European data centres consume large and growing amounts of electricity, and many facilities still rely on air-based cooling approaches that struggle with increasingly power-dense chips. As computing loads rise, so does the potential for heat recovery—but typical data-centre excess heat is low temperature, which can limit practical use. CoolHeatDC addresses both challenges by combining advanced two-phase immersion cooling with heat upgrading, aiming to improve cooling efficiency while delivering higher-value heat for the energy system.
Objectives
CoolHeatDC aims to develop an enhanced, integrated heating and cooling solution that:
- Enables climate-friendly cooling of hyperscale data centres (above 50 MWel)
- Supports energy- and cost-efficient recovery of excess heat
- Upgrades heat quality so it can be used in district heating and industrial heating, replacing fossil-based heat where relevant
- Delivers scalable, safe and reliable two-phase immersion cooling concepts, directly coupled to a heat pump
- Uses natural working fluids
- Provides validated computational tools to support design and operation across climate zones and at different scales
What we are developing
The project develops and lab-tests two-phase immersion cooling (2PIC) systems where servers are cooled directly in a dielectric fluid that boils at controlled conditions. The concept is directly coupled to a heat pump to raise the temperature of the recovered heat to levels that better match real heating needs.
Key development areas include:
- System concepts for advanced, scalable 2PIC
- Integration principles for 2PIC + heat pump as a single heating/cooling solution
- Safe operation with natural working fluids
- Experimental testing at lab scale under simulated realistic conditions
- Modelling and simulation tools for design optimisation and techno-economic assessment