Data Centres and Heat Recovery: Technology Shifts Opening New Doors

As data storage and digitalisation continue to grow while energy prices are under pressure, data centres are placed in a clear field of tension. Facilities that require large amounts of electricity simultaneously generate significant volumes of excess heat. At a time when sustainability targets, EU regulations and geopolitical uncertainty influence how IT infrastructure is built and operated, new questions arise. How can heat be recovered efficiently? And what is required for data centres to become an integrated part of the future energy system?

These issues are part of everyday work for Anders de Maré and Mikael Anjou. De Maré works as a project sales manager focusing on critical infrastructure at ENACO, while Anjou is Country Manager Sweden at Nordic Climate Group. Together, they describe how technology is evolving and the shift currently shaping the industry.

From local to hyperscale and back to local

For a long time, Swedish companies kept their IT environments close to their own operations. On premises solutions were the natural choice, not least for security and performance reasons. Then cloud services accelerated, or as Anders de Maré describes it: “That cloud everyone thinks is a cloud but which in reality consists of enormous server parks.” This development led to large scale establishments, where the Nordic region stood out thanks to its cold climate and access to low cost, fossil free electricity.

“In the beginning, it was about the combination of cheap energy and cold weather, and northern Sweden became an important location. Getting rid of excess heat was the main issue,” says Mikael Anjou.

Today, the movement is shifting again. More companies are seeking greater physical control over their data. Behind this shift are several interacting factors: rapidly growing data volumes, rising energy costs, stricter security requirements and a changed geopolitical landscape.

“In just a few years, the view of data security has changed dramatically. Even ordinary companies are now asking whether they dare to place their data and mission critical systems with a supplier without having their own control and insight,” says Anders de Maré.

The result is growing interest in regional data centres, co location solutions and local storage, where companies have full knowledge of where their data is stored and how it is managed.

The new technical reality

At the same time as the market is changing, the technical reality within data centres has shifted rapidly. A decade ago, power per rack was often between 2 and 6 kW. Today, levels of 20 to 60 kW are more common, and the latest generation of AI driven GPU installations for training and computation are approaching several hundred kilowatts per rack. Forecasts indicate that within a few years, power levels may reach around one megawatt per rack, 1,000 kW, a clear indication of how fast development is progressing.

“The new GPU servers are liquid cooled directly at chip level, which makes it possible to recover heat energy in a completely different way than before. Most of the heat ends up in a high temperature medium, which in turn enables more efficient heat recovery,” says Anders de Maré.

Cooling technology is also undergoing a clear transition. Synthetic refrigerants, such as HFC gases, are being phased out and replaced by natural alternatives such as ammonia, carbon dioxide and hydrocarbons.

“This shift is about environment, regulation and operating economics. It affects how machines are designed, but not the objective. The goal remains to move heat from one place to another, to recover heat energy and to do so as efficiently as possible,” says Mikael Anjou.

Energy efficiency as a system issue – from design to energy hub

As power demands increase, the technical design of data centres becomes increasingly important. The EU Energy Efficiency Directive (EED) requires data centres with an installed capacity above 500 kW not only to monitor their energy use, but also to recover part of the heat they generate.

According to Anders de Maré, this means that data centres increasingly need to be seen as part of the energy system rather than merely as IT infrastructure.

“That is where energy enters, is managed and then transferred into other systems.”

Mikael Anjou emphasises the obvious benefit of recovering heat instead of letting it go to waste.

“It makes no sense to put large amounts of energy into a server hall and then let all the heat disappear into the air. Every kilowatt hour that can be recovered makes a difference, both economically and socially.”

Data centres in a new system role

With the technology now available, it is becoming easier to integrate data centres into local energy systems. This applies both to fourth generation district heating networks, where heat pumps raise temperatures to 70 to 80 degrees, and to fifth generation low temperature energy systems. In these energy loops, temperatures are closer to ground level, enabling multiple actors to both supply and receive energy.

This opens up new applications for housing, retail, sports facilities and entire districts. According to Mikael Anjou, economics is increasingly driving this development.

“The higher energy prices become, the more rational it is to connect systems. All logic suggests that more actors will share energy with each other in the future.”

Many of the solutions are also located very close by, in some cases literally wall to wall.

“Waste heat from one facility often disappears into the air while a neighbouring property buys district heating. Situations like this are starting to change as technology matures and energy prices rise. Another contributing factor is financial incentives. Through programmes such as Klimatklivet, parts of investments in energy collaborations can be financed, shortening payback times and making projects more attractive,” says Anders de Maré.

At the same time as AI development and growing data volumes make data centres increasingly critical to society, they are also taking on a more central role in the energy system. The heat generated in server environments can be used where people live, work and consume energy.

Integrating data centres into future energy solutions is therefore not only about technical possibilities, but equally about urban planning, business models and policy instruments.

“Data storage is exploding at multiple levels. That drives an enormous need for capacity, and then it becomes even more important to recover the energy that is being used,” concludes Mikael Anjou.

Clima Energy Nordic – a meeting place in a changing energy system

As Sweden expands both digital infrastructure and more energy efficient districts, the need increases for forums where technology suppliers, energy companies, property owners and industry can meet. Against this background, Clima Energy Nordic is being established as a collective arena for knowledge exchange, discussions about technological shifts and the development of solutions where data centres become an integrated part of the future circular energy system.

Clima Energy Nordic is the Nordic region’s new meeting place for sustainable and energy efficient buildings and facilities. With a focus on efficient energy use in heating, ventilation and cooling for indoor climate, property owners, investors, installers, suppliers, consultants, researchers and decision makers come together to drive the development towards sustainable buildings, facilities and profitable investments.

About Clima Energy Nordic