Published 2026-11-05 · Event 2026-11-04 · The editorial team

atNorth and Calentix sign development agreement on heat recovery from SWE04 to Långsele district heating

atNorth and the heat-recovery developer Calentix have signed a project development agreement on recovering surplus heat from atNorth's planned SWE04 data centre in Sollefteå. According to Calentix, the first phase would deliver 1.6 MW of heat to the Långsele district heating network, with potential for about 20 MW. The target for the first heat delivery is the second quarter of 2029.

The agreement was described in an article published by atNorth and Calentix on 4 November 2026 and on Calentix's project page for SWE04. Under the agreement, Calentix leads the technical, commercial and financial development of the heat recovery solution. atNorth provides access to the surplus heat from SWE04, together with site integration and the necessary infrastructure interfaces. Calentix writes that its aim is to take the project to an investment decision and then own and operate the recovery plant as an independent heat producer.

The heat would go to the district heating network in Långsele, which according to Calentix lies about 2 kilometres from the site. A possible second phase could supply the larger network in Sollefteå, about 10 kilometres away. Both networks are operated by the utility Adven. Calentix gives 1.6 MW of recovered heat in the first phase, with potential for expansion to about 20 MW, set against the 300 MW planned for the data centre.

According to Calentix, a feasibility study completed in April 2026 found heat recovery feasible and no regulatory or environmental obstacles; the district heating operator and the municipality were positive in the consultations. The company describes Långsele as close to viable on the modelled assumptions, with the remaining gap depending on commercial structuring and possible regional investment support. Sollefteå would require a considerably larger investment, dominated by the transit pipeline, which Calentix says no single party is expected to carry without substantial public support.

Calentix puts the project at stage 5 of 8, commercial negotiations, in November 2026. Heat price, land access, grid connection terms and co-funding are under negotiation through 2026. A heat purchase agreement is targeted for 2027, and the investment decision follows that agreement and detailed engineering. Construction is planned from 2028 and heat delivery from 2029, with the second quarter of 2029 as the target for the first delivery.

atNorth announced SWE04 in February 2026 as a 300 MW data centre on a 50-hectare plot at Hamre Industrial Park in Långsele, expected to be operational in the first half of 2028. Calentix writes that the data centre is expected to be operational in 2028 and that recoverable heat becomes available as operation ramps up.

Why it matters

It is the first published heat-reuse plan for SWE04 with a named district heating network, a heat figure and a timetable. The plan is at the development stage: no heat purchase agreement or investment decision exists yet.

What remains unknown

Whether Adven has agreed to buy the heat, the heat price, the investment cost, whether regional or public support will be granted, and whether the second phase to Sollefteå will go ahead are not stated. Construction status of the data centre itself is not reported in the sources.

Sources