Published 2026-09-12 · Event 2025-07-03

Vatajankoski’s Merikarvia start is a 1.5 MW heat module, not a hyperscale heat contract

Vatajankoski’s 3 July 2025 note says a 1.5 MW modular data centre has started at the old sawmill in Merikarvia, with E-Heat operating the servers and waste heat fed into the district-heating network. A small heat-reuse start is not a hyperscale offtake deal.

Vatajankoski’s 3 July 2025 start note is the dated Merikarvia source used here. It says a new 1.5 MW data centre has started in the old sawmill area and will produce district heat without combustion. The centre was built by Vatajankoski and E-Heat and is operated by E-Heat. Heat from server cooling water is fed into the local district-heating network. A 1.5 MW start is not a hyperscale campus.

The oil-replacement sentence must stay a source-claim sentence. Vatajankoski writes that the waste heat will almost entirely replace the light fuel oil used after the Metsä Fibre sawmill shut down. Merikarvia municipality’s later 23 October 2025 page says the centre was commissioned on 23 June 2025, that oil heating plants have been closed since start-up, and that calculations put waste-heat cover at 90–95 percent of the town’s district-heating need, depending on the winter. Those are printed claims. They are not a measured annual offtake reproduced here.

The modular sentence must stay a modular sentence. Vatajankoski writes that the modular design allows power to be increased as needed. The municipal page says the rest of the heat is still produced with oil, with a plan to develop an alternative so that light fuel oil remains only as backup. A growth option and a backup plan are not a signed second module.

Related grid notes stay on their own pages. Helen’s OnZero and Fortum’s Espoo heat-pump notes, Eskilstuna’s SDC heat paper and other Finnish or Swedish heat-reuse rows are different dates and different counterparties. This article does not import a capital-region heat contract into a Merikarvia sawmill day.

DataCenterSweden records 3 July 2025 as a Vatajankoski Merikarvia start notice, with the municipal page as the dated commissioning-and-share claim. No project identifier is attached. The next update would need a later primary source that names a measured annual heat volume, a second module or a hyperscale counterparty. Until then, 1.5 MW stays the printed module — not a Finnish hyperscale heat deal.

Why it matters

A live Finnish heat-reuse headline is easy to file as a large district-heating offtake. The July note is usable only if 1.5 MW stays 1.5 MW — not a hyperscale contract.

What remains unknown

Neither page publishes a measured annual heat volume, a second module size or a hyperscale tenant.

Sources