atNorth Teams with Calentix to Route up to 20MW of Sollefteå Data Center Heat into Swedish District Heating

Swedish heat recovery firm Calentix will lead the development and financing of a heat reuse solution at atNorth's SWE04 data center in Sollefteå, Sweden, under a project development agreement signed by the two companies.

Calentix to lead development and financing of heat recovery project

The arrangement is designed to channel surplus heat from the facility, which will have a capacity of up to 300MW, into the Långsele district heating network operated by Swedish utility Adven. The partners have set a target for the first delivery of heat in Q2 of 2029. In the project's first phase, heat recovery is expected to total 1.6MW, with the potential to expand to approximately 20MW. Connecting the data center to the heating network will require between 2km (1.2 miles) and 10km (6.2 miles) of new pipelines. Under the agreement, atNorth will provide access to the surplus heat generated at SWE04, along with site integration and the necessary infrastructure interfaces.

Calentix, meanwhile, takes responsibility for leading the project's development and financing, with atNorth making the surplus heat available for dispatch to the local heating network. The companies said the structure will allow "each partner to focus on what they do best, while creating a practical way for the heat to be used within the local energy system and demonstrating how collaboration between specialist partners can make a difference." According to the partners, the core challenge of the project will be finding a solution that creates value for both sides.

Feasibility confirmed but commercial viability still to be proven

An early feasibility study examining the project's potential has already been completed. The study confirmed that heat recovery is technically feasible and that there is local interest in exploring the opportunity further.

The focus now, the partners said, is determining whether the project can become technically and commercially viable. That work covers technical design, site planning, commercial principles, and the agreements needed between the different parties. A heat purchase agreement is targeted for signing in 2027. Once that step is taken, the partners will make a final investment decision on the project.

SWE04 takes shape at Hamre Industrial Park

atNorth announced plans for the SWE04 data center in February. The site, located at Hamre Industrial Park in Långsele, will be developed on a 50-hectare plot. The facility will support direct liquid cooling, and the company said it will be able to support densities of up to 1MW per rack.

Second Swedish facility under development in Stockholm

atNorth currently operates one facility in Sweden. SWE01, located in Kista, a suburb of Stockholm, was launched in 2022 and offers 12MW of capacity across 6,400 sqm (68,890 sq ft).

The site is home to Swedish cloud provider 6G AI Sweden and AlphaTon Capital Corp. A second Stockholm facility, known as SWE02, is in development. Announced last month and set to be located close to SWE01, the new facility will offer 30MW and is due to go live in Q4 2027.

Heat reuse extends atNorth's footprint to northern Sweden

The agreement with Calentix is the latest in a series of heat reuse deals signed by atNorth in recent years. Most recently, in August, the company partnered with sustainable infrastructure firm Selected Group on a heat reuse project at its DEN02 data center campus in Ølgod, Denmark.

The Calentix deal extends that approach to northern Sweden. Should the project pass its upcoming commercial and technical viability milestones and reach a final investment decision, surplus heat from the Sollefteå facility could eventually supply as much as 20MW to the Långsele district heating network operated by Adven.