We advised Oomi Solar Oy on the sale of a 250-megawatt solar power project portfolio to Suomen Aurinkovoima Oy. The portfolio consists of ten separate projects, marking a significant development in the Finnish solar energy market and enabling over EUR 100 million in investments. Construction of the first projects is expected to commence as early as 2025, with sites located across various regions of Finland.
30.5.2025
Oomi Solar Sale of solar power project portfolio
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Downing – Acquisition of the entire share capital of Tornionlaakson Voima
We advised UK-based investment company Downing in its acquisition of the entire share capital of Tornionlaakson Voima Oy. Tornionlaakson Voima owns three hydropower plants in the Tengeliönjoki river system – the Portimokoski power plants in Ylitornio, the Jolmankoski power plants in Raanujärvi and the Kaaranneskoski power plants in Sirkkakoski. The power plants produce a total of approx. 45 gigawatt-hours of electricity per year. Tornionlaakson Voima’s daily operations will continue normally, and the transaction will not affect customers. The consummation of the transaction is subject to the approval of the Ministry of Economic Affairs and Employment. Downing has over 35 years’ experience in providing a wide range of investment solutions to the needs of institutional investors, advisers and retail investors. The company manages over £2 billion in assets in both the private and public markets and its current hydro power portfolio includes approx. 50 hydro power plants in the Nordics.
Case published 27.3.2026
Terrafame – Environmental and water management permit processes concerning the company’s entire operations and the KL1 side rock area
Castrén & Snellman successfully assisted Terrafame Ltd in environmental and water management permit processes concerning the company’s entire operations and the KL1 side rock area, on which the Supreme Administrative Court issued its decision on 12 February 2026 (KHO 366/2026 and 367/2026). The changes made to the decisions of the Vaasa Administrative Court as a result of Terrafame’s appeals, enable the company to implement its new strategy and develop its operations as planned. The decisions of the Supreme Administrative Court brought the nearly ten-year-long permit process to a close.
Case published 20.2.2026
Brookfield – EUR 1 billion holdco financing for DayOne Data Centers
We advised a leading global investment firm Brookfield, alongside a global sovereign wealth investor, on the Finnish law aspects of a EUR 1 billion holdco financing for DayOne Data Centers, a Singapore-headquartered developer and operator of hyperscale data centres. Structured as a seven-year secured holdco financing facility of €500 million, expandable to €1 billion – and secured by DayOne’s Finland platform – the financing will support the rollout of hyperscale developments in Lahti and Kouvola, providing nearly 300MW of planned capacity across Finland. The proceeds will also support DayOne’s global expansion across the EU and APAC, with flexibility to allocate to other key growth markets as required.
Case published 29.1.2026
Rabobank – Financing arrangement for Olana Energy
Castrén & Snellman acted as legal advisor to Coöperatieve Rabobank U.A. in its capacity as sole lender and hedging bank providing senior financing to Olana Energy for a Battery Energy Storage Systems (BESS) portfolio in Finland. Our advice included preparing a legal due diligence report on the projects as well as advising on the negotiation of the various finance and project agreements. Olana Energy is a management-owned fast-growing independent power producer with an international pipeline of over 1 GW. The diversified portfolio of assets ranging from 5 to 30 MW reinforces the Finnish grid at a granular level.
Case published 18.11.2025