• Plans for 140 MW+ expansion in Stockholm by 2029
• 40 MW power feed agreement signed for Stockholm 5 development
• First phase – 14 MW – set to go live in June 2027

Swedish data centre developer Conapto is progressing with its ‘aggressive’ expansion plans to develop an additional 140 MW+ of IT load (equal to roughly 200 MW+ of power feed) in Stockholm by 2029.

The Marguerite-backed Conapto has secured a 40 MW power feed agreement for its planned Stockholm 5 development, which translates to roughly 28 MW of deliverable IT capacity, according to Stefan Nilsson, CCO.

The developer hopes to begin construction on the greenfield project by early spring.

The first phase of the project – roughly half of the total capacity – is expected to launch in June 2027, while the second phase will be developed according to customer preferences.

Customers are yet to be secured for the facility but the developer will begin marketing once the building permit has been confirmed at the end of January or beginning of February 2026.

“Given the current shortage of data centre capacity in Europe, we’re quite confident that we will have a lot of interest before it’s even launched, with an expectation to bring in somewhere between one and five customers,” Nilsson said.

Marguerite is responsible for the funding of these developments, and most recently issued SEK 500m (EUR 45.98m) in senior secured bonds, as reported in May 2025.

At present, Marguerite is not exploring acquisition options for Conapto, and is entirely focused on developing its own facilities. Nilsson highlighted, however, that with a new owner could come a new strategy.

“Marguerite will sell the company at one point in time, that’s the nature of the business – I think it will actually be sooner rather than later,” Nilsson explained.

Current portfolio: Stockholm 1, Stockholm 2, Stockholm 3 and Stockholm 4

At present, Conapto operates four facilities in Stockholm. Stockholm 5 will be located in close proximity to Stockholm 3, making up the North Campus, while Stockholm 2 and Stockholm 4 will be nearby one another and make up the Southern Campus.

“It was a strategic decision by our board of directors to focus all our efforts in Stockholm given it is an attractive place to put capacity,” Nilsson explained

The 1 MW Stockholm 1 site, based in the city centre, is operational and already hooked up to the district heating network. The facility is used by customers as a connectivity hub or as a backup facility for smaller deployment.

Stockholm 2 – located in the Southern part of the city – is also operational, currently providing 4 MW of IT capacity to its customers. The traditional retail colo site is hooked up to the district heating network in Stockholm and is one of the main production sites, despite it not being able to manage any high density loads.

Stockholm 3 – also a traditional retail colo site paired up to the district heating network – is based in the northern part of the city, offering 6 MW of IT capacity. Prior to the development of Conapto’s fourth site, this was the company’s main facility.

In September 2024, Stockholm 4 went live with 18 MW of IT load (equating to a 28 MW power feed). The site is designed for mainly high-density air- and liquid-cooled deployments for AI purposes. The site has just 1 MW of remaining capacity available, with the rest fully sold out.

“Stockholm 4 is our newest project and our current flagship site,” Nilsson said. “We built it from ground up as a greenfield project, whereas Stockholm 1, 2 and 3 were retrofitted.”

Nilsson recognised that, although retrofitting is a sustainable way of developing, it offers its own challenges when it comes to upgrading infrastructure and technology, specifically referencing liquid cooling which requires higher ceilings and bigger loading docks.

“Moving forward, greenfield will be a lot more relevant for developers and probably cheaper, even if you could argue that from a sustainability perspective a retrofit is a wise thing to do,” Nilsson said.

District heating network

When it comes to developing new sites, including the Stockholm 5 project and beyond, Conapto intends to work alongside the district heating owners and utility companies in order to carve our new capacity.

“We secure power and land pretty much on the same basis,” Nilsson explained. “It’s a way for us to insert ourselves and get power in a more efficient way by making ourselves an asset to the community.”

Between 30-70% of waste heat from the Conapto facilities can be reused as part of the district heating system, according to Nilsson.

*This story was originally published exclusively for NPM Europe subscribers.