Under an EU-funded research project an AM cooling system has been developed for use in data centres that reduces energy use and extends computer lifespan.
In the recently concluded AM2pC project, organised by M-ERA.NET, the partners demonstrated the passive two-phase cooling technology that achieved a cooling capacity of 600 watts in tests, 50% more than the original target of 400 watts.
Data centres face a growing challenge with increasing energy consumption for cooling servers and GPUs. In countries like Ireland, for example, data centres use such a large share of total energy consumption that legal restrictions have been introduced.
“Besides the actual IT hardware, the corresponding cooling infrastructure is one of the major energy consumers in a data centre – and therefore the greatest potential to improve overall system efficiency,” explained Simon Brudler, Additive Manufacturing specialist and senior consultant at Danish Technological Institute.
At the same time, GPU power consumption has risen from 100–200 watts just a few years ago to several hundred or even kilowatts today, so there is also a need for more efficient cooling.
Paw Mortensen, CEO of Heatflow, who led the AM2pC project, shared, “We are seeing a development where the power density in servers is increasing faster than ever before, and traditional air cooling is simply no longer sufficient. With our two-phase solution, we can remove heat passively without pumps or fans, which significantly reduces the energy consumption for cooling.”
Passive cooling without energy consumption
The new solution differs from conventional air cooling by using a coolant that evaporates at the hot surface. The vapor naturally rises due to differences in density, condenses elsewhere (where it releases heat), and returns as liquid through gravity. This passive two-phase process with coolant, a so-called thermosiphon principle, requires no pumps and thus consumes no energy for heat removal. At the same time, evaporation is much more efficient than traditional cooling with air and liquid, so the amount of heat removed from the computer chip is much higher, and the chip remains cooler, helping to extend its life.
The key component in the system is an evaporator, which Heatflow and Danish Technological Institute have developed and manufactured with AM.
Simon Brudler added, “By 3D printing the component in aluminium, we can integrate all necessary functions into a single part. This eliminates assembly points, reduces the risk of leaks, and makes the component more reliable. At the same time, we use only one material, which makes it easier to recycle.”
Enables reuse of excess heat
In addition to validating the performance of the cooling system, the team identified uses for the waste heat. The solution removes heat at temperatures between 60 – 80°C and, when extracted at such high temperatures, this has the potential for use directly in the local district heating network. The excess heat could also be used for other industrial processes, such as in the food and beverage, textile, paper and pulp sectors, or in agriculture for heating greenhouses.
In comparison, traditional air cooling of servers typically removes heat at lower temperatures, making it less suitable for district heating and industrial processes.
Brudler added, “In the project, we did not focus on the integration with district heating itself, but we have demonstrated that the technology enables it. This is an important step toward more energy-efficient data centres that can contribute positively to the overall energy balance.”
Less material use and better recyclability
Besides the energy savings during operation, the project also shows environmental benefits in manufacturing. By using Additive Manufacturing, the overall material usage is reduced compared to conventional solutions that consist of several components made of different materials.
And since the component is produced from a single material, it can be more easily recycled at the end of its lifetime, as there is no need to separate materials.
Author: Andy Cormack
