Sesterce announces €10bn AI campus at former Finnish paper mill as site sale, permits and backers remain open
The French company says it has signed an unnamed AI laboratory as its customer and plans a 200-megawatt first phase at Kaipola in Jämsä, rising to 600 megawatts. The site is not yet in its hands, and its financial backers have not been named.
Martti Asikainen | 13.10.2026 | Photo by Adobe Stock Photos
French AI infrastructure company Sesterce has announced plans to invest more than €10 billion in an AI data centre campus at the former Kaipola paper mill in Jämsä, central Finland. It expects about 2,000 jobs during construction and about 300 once the campus is fully operating. UPM closed the Kaipola mill in early 2021, when it employed more than 400 people.
The first phase would be a 200-megawatt facility cooled by liquid. A megawatt measures the electrical power a data centre can draw. A second phase would raise capacity to 600 megawatts. Over the longer term, Sesterce aims to build more than one gigawatt (1,000 megawatts) of AI capacity in Finland. It says this would be on existing industrial sites and in line with market demand.
Reusing the mill’s infrastructure
The company plans to reuse the site’s power grid, water systems, buildings and logistics links. Its chief executive, Youssef El Manssouri, said the goal is to “preserve the area’s industrial identity”. Chief executive of network operator Elenia, Jorma Myllymäki, said the site’s high-voltage connection gives a “solid foundation” for the first phase. Sesterce says it will work mainly with Finnish contractors.
The statement says works are planned to start in 2026. El Manssouri told Yle that site clearance and early interior work are already under way, and that the first construction phase will begin before the end of the year. AFP reported that Sesterce said works had begun and that commissioning is planned for 2027.
An unnamed customer, an unsold site
El Manssouri told Yle that the investment decision has been made and a contract signed with the future customer. He described it as one of two leading AI laboratories but did not name it. He also declined to name the project’s financial backers.
The site belongs to the real estate company Kaipola Green Port. Its board chair, Martti Inkovaara, told Yle that talks on selling the whole site to Sesterce are at an advanced stage. He did not disclose a price. Several companies rent space there, and it will be up to Sesterce whether they can stay.
Sesterce Group is registered in Marseille and entered the French commercial register in 2021. Its turnover was €11.95 million in 2024, according to register data cited by Yle. The report does not say whether that covers all of the group’s entities, which the company’s statement places in France, the United States and Singapore.
What Sesterce has promised
Sesterce commits to enabling one megawatt of new renewable generation capacity in the Finnish grid for every megawatt the campus consumes. It says this will happen within ten years of the campus opening, and only newly built capacity will count. Cooling will use a closed-loop liquid system, rainwater and recycled water, not drinking water.
A €10 million community fund, created when the campus is commissioned, would finance projects chosen by the town and its residents. An independent third party will audit the commitments, and the results will be published each year, the company says.
El Manssouri told Yle that Kaipola was chosen for its minimal environmental impact. “Many supercomputer projects destroy a lot of nature,” he said.
Permits still ahead
Jämsä’s town manager, Jori Reijula, told Yle that he learned of the plans only a few weeks ago. The project matters for a town whose population and vitality have declined, he said. But many permit processes remain, and it is not time to celebrate. He said he wants to see progress “before we start declaring that a data centre is here”.
Much of what is known rests on Sesterce’s own account, including the signed customer, the schedule and the job figures. The statement does not list the permits still needed. The renewable pledge is measured in megawatts of capacity, not energy produced, and its deadline is ten years after the campus opens.
