Heating using Waste Heat from Servers: Heat pumps at TU Dresden generate CO₂-free district heating all year round

District heating in Dresden is to be made climate-friendly step by step, without CO₂ emissions, through the use of various innovative technologies. One of these technologies is the use of waste heat, which is being implemented for the first time in Dresden at the TUD Dresden University of Technology. Three large heat pumps with a total capacity of 3.9 megawatts convert the excess waste heat from the TUD’s high-performance computing systems into district heating. Up to 24,000 megawatt hours of green heat are generated annually, enough to supply 3,700 average Dresden households. Compared to conventional district heating generated using gas, this technology avoids around 2,700 tons of CO₂. Since 2023, the state-owned enterprise Sächsisches Immobilien- und Baumanagement (SIB), the municipal utility company SachsenEnergie, and TUD have jointly implemented one of the first waste heat projects of its kind in Germany.

For the Saxon state capital Dresden, this represents an innovative step toward climate-neutral heat supply. Mayor Dirk Hilbert emphasizes the importance of the project: “The sustainable use of waste heat from TU Dresden’s high-performance computing systems exemplifies how we can achieve our climate goals in Dresden: with tailored, innovative, and pragmatic solutions from our local partners. Using modern technologies, TU Dresden and SachsenEnergie are demonstrating how we can achieve greater independence from gas in our heat supply. We intend to continue pursuing this path toward decarbonization.”

© Martin Förster

Flagship project for Dresden’s heating transition: year-round usable heat 

SachsenEnergie currently operates three large heat pump systems in Dresden. A special feature of the data center’s waste heat is that this usable heat is available all year round. “This will give us a constantly available heat source for Dresden’s district heating network,” says Dr. Axel Cunow, CFO of SachsenEnergie, adding: “By operating the heat pump system, we are taking another decisive step toward making Dresden’s district heating greener. The project shows that the heat transition can only succeed through collaboration—with pioneering technology and strong partners. With such flagship projects, innovation also means continuously learning, adapting, and optimizing.”

Maike Heitkamp-Mai, Sustainability Officer at TUD, explains: “The heat pump project exemplifies our sustainability strategy, through which we at TU Dresden have set the goal of becoming greenhouse gas-neutral by 2035 in the areas of activity for campus and operations. The close collaboration with SachsenEnergie and SIB to utilize the waste heat from our data center impressively demonstrates how science and technology are driving the energy transition forward with concrete solutions.”

Implementation of TUD’s sustainability strategy with modern state infrastructure

The technical building for the heat pumps and the civil engineering work for the media line were constructed under the direction of the SIB Dresden II branch. Oliver Gaber, Commercial Director of SIB, states: “As the real estate and construction representative of the Free State of Saxony, we see ourselves as pioneers of ecological and economic responsibility. With this future-oriented project, we are not only sending a clear signal for greater sustainability and energy efficiency, but also proving that innovative solutions and responsible action indeed go hand in hand. The use of waste heat and the insights gained from this award-winning pilot project are essential steps toward a sustainable future.”

In addition to security, power density, and high availability, energy efficiency was also a key design goal in the planning of the TUD data center. The building concept, optimized for particularly efficient air cooling, was already honored in 2014 with the German Data Center Award in the category “Energy- and Resource-Efficient Data Centers.” The consistent use of hot water cooling for the high-performance computers now also allows for the efficient reuse of the resulting waste heat.

This is how the heat pumps work

The waste heat generated by the systems involved in high-performance computing is absorbed by cooling water and fed to the heat pumps at a temperature of up to 55 degrees Celsius. The three electric-powered systems extract the waste heat from the water and raise its temperature to around 90 degrees Celsius. The heat is then fed into the surrounding district heating grid. By using the heat pumps, the waste heat can be utilized year-round and converted into up to 24,000 megawatt-hours of green district heating per year. Particularly in the summer months, this avoids the need for additional re-cooling of the cooling water used by the high-performance computers.

Recipient of the ‘Energy Efficiency Award”

The heat pump system is part of a collaborative project funded by the Federal Ministry for Economic Affairs and Climate Action through the National Climate Initiative. The project was already awarded the “Energy Efficiency Award” by the German Energy Agency (dena) in 2024 in the category “Achieve More Together!”. The combination of energy-efficient data center operation, 100% renewable electricity, and intelligent waste heat utilization makes the project unique across Germany and a model for municipalities, research institutions, and energy suppliers.

In total, SachsenEnergie is investing approximately EUR 4.4 million in the facility, of which EUR 2.1 million will be funded by the BMWK as part of the National Climate Initiative.

Media inquiries: SachsenEnergie
Nora Weinhold
Press and Media Relations 
Email:
Tel.:  +49 351, 5630, 23671
Cell: 0174 1502935

Media inquiries: SIB
Alwin-Rainer Zipfl
Press Officer
Tel.: +49 351 8135 1260
Alwin-Rainer.Zipfl@sib.smf.sachsen.de

Media inquiries: TUD
Jacqueline Papperitz
Project Coordination/Public Relations
CIDS - Center for Interdisciplinary Digital Sciences
Center for Information Services and High-Performance Computing (ZIH)
Email: jacqueline.papperitz@tu-dresden.de
Tel.: +49 351 463-32431