This room generates enough heat for 5,000 apartments

By clicking this article, you started a process in a data centre.

This process generates heat.

Brilliant minds work to distribute heat through buried pipes. 

In this way, the data centre will cover the annual heat demand of more than 5,000 apartments in Oslo, Norway. 

Streaming causes greenhouse gas emissions


On a global scale, Internet traffic generates just as much CO₂ as air traffic. But a Norwegian data centre has come up with a profitable and green solution. By reusing the heat generated by your streaming activity, they reduce the carbon footprint and energy consumption considerably.

“Our ambitious climate goals call for new energy solutions for how to heat our cities, and reusing excess heat is a key part of the solution,” says Halvor Bjerke, Nordics Operational Manager with the data centre company DigiPlex.

Located in Ulven, Norway, the data centre hosts server solutions for both public and private organisations, including high-security customers in, e.g., the finance sector.

“Our business is based on trust,” says Bjerke.

Halvor Bjerke, Nordics Operational Manager with DigiPlex

All of the company’s five data centres in the Nordic countries are powered by sustainable energy sources.

“In Norway, they run on hydropower,” says Bjerke.

Heat is reused

Data centre operations generate huge amounts of heat. In the case of the data centre in Ulven, this amounts to 25 gigawatt hours a year.

“The big issue used to be how to cool data centres. That’s still on the agenda, but now we’re concerned with how to best utilise the heat for the benefit of society at large,” explains Bjerke.

The data centre in Ulven generates 25 gigawatt hours a year.

He points out that data centres account for as much as three per cent of global greenhouse gas emissions. Towards 2030, the share is expected to approach ten per cent.

“We’re constantly looking for innovative ways of reducing our carbon footprint. The project in Ulven is one example of that,” he continues.

But how does it actually work?

COWI has a long track record for designing data centres and efficient energy solutions across the world. In the Norwegian head office in Oslo, we find the man in charge of the project during the initial phase.

“It’s projects like this one that makes people want to join us,” says Alert Holtman, Project and Market Director in COWI’s Industry and Process department in Norway.

Since May 2018, he has headed the outline design with a carefully selected team of ten discipline experts, on behalf of the client Fortum Oslo Varme. All disciplines must join forces to handle the challenging task.

“In short, we put our heads together to come up with solutions. The goal is to have the heat flow from the data centre to more than 5,000 apartments in Oslo in a safe, cost-effective and environmentally optimal way,” says Holtman.

How does it actually work?

“Everything is in a liquid state. As with a radiator in a car, processors in a data centre are water cooled,” explains Holtman.

“Simply put, cold water enters the room and hot water exits the room. As the processors are cooled, the hot water is distributed into the city’s district heating system,” explains the civil engineer.

”I get to work on projects that truly make a mark on our society, for instance by reducing greenhouse gas emissions.”

Alert Holtman, Project and Market Director, Industry and Process, COWI

Working to limit greenhouse gas emissions

COWI plays a central role in developing profitable and green solutions for the international industrial and energy sectors. Holtman explains that sustainability is at the core of the company’s business model when recruiting talents, landing new projects and developing solutions.

“I get to work on projects that truly make a mark on our society, for instance by reducing greenhouse gas emissions. From renewable energy solutions over data centre heat recovery to carbon capture.”

"Engineers are an important part of the green transition and I’m proud to make my contribution. A project like the Ulven data centre offers professional challenges and is meaningful,” says Holtmann.
COWI's client is Fortum Oslo Varme AS, which owns and operates the Oslo district heating system.

The majority of the Oslo district heating system was extended over the past three decades. 

Today, more than 600 kilometres of district heating pipes run underneath Oslo.

At any given time, the pipes circulate 30 million litres of water at more than 100 degrees Celsius.

Responsible for 30 million litres of circulating water: The project could be a blueprint

Business Developer Anders Westin with Fortum Oslo Varme believes that the Ulven energy central and using the data centre excess heat are profitable as well as a win-win-win situation.

“So far, it’s been great working with COWI on this project. We are confident that COWI will continue to deliver high-quality services on whatever projects they are involved in,” he says.

Anders Westin is a business developer with Fortum Oslo Varme.

More than 20 per cent district heating

In your opinion, what has been the critical success factors for the project?

“Competencies,” says Westing initially, then adding the capacity and ability to execute.

More than 20 per cent of the Norwegian capital’s energy demand is covered by district heating. Historically, much of the heat is generated by energy recovery from waste.

“According to plan, the project in Ulven will be completed and operational in the course of 2021. This is a full-scale pilot project, and if it’s successful, Ulven will be a blueprint for other projects when we link excess heat sources to the city’s district heating infrastructure,” he says.

Get in contact

Alert Holtman er markeds- og prosjektsjef for Industri og prosess i COWI

Alert Holtman
Project Director
Industry and Process, Norway

Tel: +47 92523266