Two Big AI Data-Centre Plans: Sesterce in Finland and an MOU in Sejong

Headline figures for AI data centres keep getting bigger, but a headline figure is not money spent. On 8 October 2026 two new plans arrived with large numbers attached: the French company Sesterce said it plans an AI campus in Finland worth “over €10 billion”, and the South Korean city of Sejong signed a memorandum of understanding (MOU) for a 7 trillion won, 360-megawatt AI data centre. Both are statements of intent. This explainer sets out what each says and what is still missing. Nothing here is investment advice.

Sesterce: a former paper mill in Jämsä

Confirmed announcement of a plan (company release). Sesterce, which describes itself as a French AI infrastructure company with entities in France, the United States and Singapore, says it is “planning a large-scale Sesterce Campus on the site of the former Kaipola paper mill” in Jämsä, central Finland [1]. “The investment of over €10 billion aims to create a renewable-powered European AI campus,” the release says [1].

The project is phased:

• First phase: 200 MW, “with works planned to start in 2026” [1].
• Second phase: capacity “expected to increase to 600 MW” [1].
• Longer term: Sesterce “aims to build more than one gigawatt of AI capacity in Finland”, on existing industrial sites [1].

Megawatts here describe how much electricity the site is built to draw, which is the usual way data centres are sized.

Sesterce says it “already has an anchor customer” but does not name it [1]. It expects about 2,000 people to be employed during construction and “around 300 people once the campus is fully operational” [1]. It also makes four public commitments, which it says will be audited by an independent third party and reported every year: to enable 1 MW of new renewable generation on the Finnish grid for every 1 MW the campus consumes, within ten years of the campus becoming operational; not to use drinking water for cooling; to set up a €10 million community fund once the campus is commissioned; and to open some facilities to the public [1].

Why a paper mill? Sesterce’s chief executive, Youssef El Manssouri, says the aim is to use “existing infrastructure, including the power grid, water systems, buildings and logistics connections” [1]. The local grid company, Elenia, says the site’s high-voltage connection “currently provides a solid foundation for implementing the first phase” (note: the first phase, not the whole plan) [1]. Jämsä’s mayor, Jori Reijula, welcomes it “provided it progresses from plans to implementation and meets the applicable requirements” [1].

Sejong: a 7 trillion won memorandum

Reported (Seoul Economic Daily); an MOU, a plan only. Sejong, South Korea’s administrative city, signed an MOU on 8 October with SK Securities, Metheus Asset Management and SeedH to fund construction of an AI data centre, according to the Seoul Economic Daily [2]. The paper reports that the companies “plan to spend a combined 7 trillion won through 2029 on a facility with 360 megawatts of capacity” [2].

The terms reported are about cooperation rather than contracts. The city says it will help with permits and “actively help the companies resolve difficulties in securing land, electricity and water”, and the companies “pledged to do their utmost to ensure the project proceeds as planned, including financing and infrastructure construction” [2]. Mayor Cho Sang-ho says the aim is to make Sejong “a leading hub for South Korea’s artificial intelligence industry” [2]. No site, operator or customer is named in the report.

Why the wording matters

An MOU records what the parties intend; it is generally not a binding commitment to spend. Sesterce’s “over €10 billion” is likewise a planned investment over several phases, not money raised. Both announcements mention exactly the constraints that slow data centres everywhere: grid power, water and permits. Sejong’s own list of things it will help with (land, electricity and water) shows they are not yet settled [2].

What this does not prove

• That €10 billion has been raised. Sesterce gives no financing details; the figure is a planned investment [1].
• That 1 GW will be built in Finland. That is a longer-term aim; only the first 200 MW phase has a planned start [1].
• Who the anchor customer is. Sesterce does not say [1].
• That the Sejong data centre will be built. It is an MOU, a plan only, and TSN has seen only a press report, not the agreement [2].
• Any dollar figure. TSN uses the euro and won amounts as announced; conversions are outlets’ own.

The Bottom Line

Sesterce plans an AI campus at a former paper mill in Jämsä, starting with 200 MW and works planned for 2026, with “over €10 billion” of investment pencilled in and green commitments it promises to have audited. In Sejong, three firms have signed an MOU to spend 7 trillion won through 2029 on a 360 MW site. Both are plans. The test will be financing, grid connections and permits, not the size of the opening number.

Sources

1. Sesterce, “Sesterce Plans a €10 Billion AI Campus in Jämsä”, newsroom release, 8 October 2026 (company announcement; the body text says “over €10 billion”). https://www.sesterce.com/newsroom/sesterce-plans-ai-campus-kaipola-jamsa-finland
2. “Sejong Lands 7 Trillion Won Deal for 360-Megawatt AI Data Center”, Seoul Economic Daily, 8 October 2026 (press report; MOU text not seen). https://en.sedaily.com/society/2026/10/08/sejong-lands-7-trillion-won-deal-for-360-megawatt-ai-data