Energy Cluster Denmark, Aalborg University, Heatflow, and R&R Consult have teamed up on a data center heat reuse project in Denmark.
The project, dubbed Green DC, seeks to reduce power consumption, cool data center servers CO2-neutrally, and send surplus heat to the district heating network and local buildings.
As part of Green DC, the companies have developed a new condenser, also known as a heat exchanger, which is connected to the servers. That heat is then sent to the district heating system via a closed circuit.
According to Ali Shghar Enkeshafi, a technology developer from Aalborg University, the cooling technology is adapted to the servers and has the same efficiency and waste heat temperature as would be seen with water cooling.
Details about the cooling method have not been shared. DCD has contacted the Energy Cluster Denmark for more information.
With the solution now developed, the next step is to make it widespread.
Paw Mortensen, director and co-founder of Heatflow, said: "The projection on data center power consumption is enormous - we are most likely talking a factor of three within the next twenty years. And with the AI calculations, which are coming to an even greater extent than before, consumption will increase even more. Therefore, we see significant market potential in offering alternative cooling solutions."
Mortenson added: "The collaboration with Aalborg University and Energy Cluster Denmark has been unique. We have seen a formula for how to achieve an innovation that makes a difference in a relatively short time.”
In November 2023, Aalborg University conducted a study looking at how district heating systems, including using local waste heat from other sectors, could reduce natural gas imports by 24 bcm by 2030, and by 2050 the untapped resources could cover twice the needed district heating level. Data centers were among the waste heat sources Aalborg cited.
Energy Cluster Denmark is the cluster organization for Denmark's energy sector, and is working towards greening the nation through energy solutions.
According to Energy Cluster Denmark, in 2025 Danish data centers are expected to consume 3,600 GWh annually, which corresponds to around a tenth of Denmark's total electricity consumption.
Heat reuse's popularity in the data center sector is increasing. Earlier this month, HPE and Danfoss teamed up on a scalable modular data center that incorporates Danfoss's heat reuse solutions. Danfoss also provides cooling and heat reuse systems for Google data centers.
In Germany, following the implementation of the September 2023 Energy Efficiency Directive, data centers will have to report on how they use their waste heat, and data centers over 200kW built from 2025 will be required to reuse 20 percent of their heat by 2028.
Projects in Germany reusing wasted heat include the University of Oldenburg's data center, and Equinix has also joined a district heating scheme in Frankfurt, and is involved in similar schemes elsewhere in Europe. Digital Realty is also looking to join a district heating scheme in Frankfurt in partnership with Mainova.
In the UK, Deep Green uses waste heat for local swimming pools, with the initial deployment at a leisure center in Exmouth, Devon.
