atNorth targets 20MW heat recovery at Swedish SWE04 campus

atNorth has signed a project development agreement with Swedish heat recovery firm Calentix to capture surplus heat from its planned up-to-300MW SWE04 data center in Sollefteå, Sweden, with first heat delivery targeted for Q2 2029.

The first phase of the project is expected to recover 1.6MW of heat, with potential to expand to approximately 20MW. Connecting SWE04 to the nearby Långsele district heating network — operated by Swedish utility Adven — will require between 2km (1.2 miles) and 10km (6.2 miles) of new pipelines.

Under the agreement, Calentix will lead development of the heat recovery solution and its financing. atNorth will provide access to surplus heat from SWE04, along with site integration and the necessary infrastructure interfaces.

What has been decided so far?

The partners have already completed an early feasibility study. It confirmed that heat recovery at the site is technically feasible and found local interest in exploring the opportunity further.

The next stage determines whether the project can become technically and commercially viable. Work now covers technical design, site planning, commercial principles, and the agreements required between the parties. The companies identified the core challenge as finding a solution that creates value for both sides.

In a joint statement, the partners said the division of roles 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."

The companies target signing a heat purchase agreement in 2027. A final investment decision follows that signing.

What is SWE04?

atNorth announced plans for SWE04 in February. The site sits at Hamre Industrial Park in Långsele on a 50-hectare plot and will support direct liquid cooling at densities up to 1MW per rack.

Sweden currently hosts one operating atNorth facility. SWE01, located in Kista, a suburb of Stockholm, launched in 2022 and offers 12MW of capacity across 6,400 sqm (68,890 sq ft). Its tenants include Swedish cloud provider 6G AI Sweden and AlphaTon Capital Corp.

A second Stockholm facility, SWE02, is in development. Announced last month and located close to SWE01, it will offer 30MW and is due to go live in Q4 2027.

How does this fit atNorth's heat reuse record?

The Calentix deal extends a pattern of heat reuse agreements 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.

SWE04's potential 20MW output would rank among the more substantial Nordic data center heat recovery schemes. The 2029 target date, however, leaves a two-step gate — the 2027 heat purchase agreement and the final investment decision — before any heat flows. The project now rests on proving commercial viability.