Home District Energy News Aalborg CSP delivers heat pump station to the EU’s largest geothermal project.

Aalborg CSP delivers heat pump station to the EU’s largest geothermal project.

by Linda Bertelsen
Innargi_Geothermal drilling

PRESS RELEASE | OCTOBER 1, 2024

The North Jutland-based renewable energy specialist Aalborg CSP has partnered with Innargi to supply an integrated heat pump station of approximately 18 MW for a major geothermal project in Aarhus, Denmark. The station includes a 10 MW electric heat pump that will absorb energy from underground geothermal water and transfer it to Kredsløb’s district heating network in northern Aarhus.

Solar and wind energy have gained traction in Danish district heating plants and utilities, but what happens when the sun isn’t shining and the wind is calm? The answer lies beneath our feet. The Earth’s core holds vast amounts of renewable energy in the form of geothermal heat.

Geothermal district heating for Aarhus

Innargi and the utility company Kredsløb have recognized the potential of geothermal district heating and initiated a collaboration to bring this energy source to Aarhus. Currently, they are working on a project that, once completed, will consist of 14–17 geothermal wells spread across seven different locations in Aarhus.

With a total capacity of 110 MW, the geothermal system will supply up to 20% of Kredsløb’s district heating needs, equivalent to the annual heat consumption of 36,000 households. The full installation is expected to be completed by 2029, making it the largest of its kind within the EU.

Tailored heat pump station

The first groundbreaking took place in Skejby, Aarhus, where the initial geothermal plant is expected to deliver its first sustainable energy to northern Aarhus in the second half of 2025. After a tender process, Innargi chose Aalborg CSP as a partner for the project.

In collaboration with Solid Energy A/S, Aalborg CSP has designed a modular heat pump solution based on hydrocarbons, capable of handling the sometimes fluctuating flow of geothermal water and delivering the desired high supply temperature. The heat pump station in Skejby will have a capacity of up to 18 MW of heat and provide temperatures up to 95°C to Kredsløb’s district heating network.

Aalborg CSP_Innargi_contract signing

“Innargi brings fantastic know-how and deep expertise in geothermal energy, and we share their ambitious goal of creating the most affordable district heating. We are incredibly proud and excited to contribute our experience in heat pump integration and project execution to realize this groundbreaking piece of district heating infrastructure, which will benefit cities across Denmark and Europe,” says Svante Bundgaard, CEO of Aalborg CSP.

In addition to a heat pump station optimized for geothermal energy, the collaboration phase focused on designing a building standard that Innargi and Kredsløb can use for other geothermal installations. The building design also had to meet several visual and architectural requirements to fit seamlessly into the local environment at the desired location in Skejby.

“We are very pleased with the solution – and especially the collaboration – we have developed with the team at Aalborg CSP over the past few months. The facility will be the first of its kind in Aarhus, and it has been crucial that, through the collaboration phase, we identify the best and most sustainable solutions to deliver stable, green district heating to the residents of Aarhus for many years to come,” says Lars Bjørn Heineke, Project Manager at Innargi.

Aalborg CSP has developed a building design and optimized the technical installations in collaboration with Innargi’s technical team. The goal of the collaboration was to deliver a cost-effective, complete heat pump station and solution that fully harnesses the potential of geothermal resources.

The building is expected to be completed in January 2025, after which the installation of the heat pump and technical systems will begin. The facility is expected to be operational by fall 2025.

Project facts:

  • Client: Innargi
  • End Client: Kredsløb
  • Capacity:
    • Heat pump: 10 MW at up to 95°C
    • Total system: 18 MW at up to 95°C
  • Natural refrigerant: Hydrocarbon (isobutane and propane)
  • System provider: Aalborg CSP A/S in collaboration with Solid Energy A/S (heat pump), Svend Aage Christiansen A/S (building), and Soft og Teknik (electrical)
  • Scope of delivery: Heat pump station including building, heat pumps, technical installations
  • Location: Skejby, Aarhus

About Aalborg CSP

Aalborg CSP is a leading developer and provider of innovative renewable energy solutions. Our vision is to Change Energy and transform how energy is produced and managed. We design and deliver green solutions and integrated energy systems based on solar, energy storage (within Power-to-X, such as PTXHEAT and PTXSALT), heat exchangers, and more for industries and power plants worldwide.

To read more about Aalborg CSP, visit www.aalborgcsp.com or the DBDH profile here.
You can find more information about Innargi here.