Joel Aartolahti

Associate, Member of the Finnish Bar

Services

  1. Environment, Energy & Green Transition

Contact details

I advise our clients in matters related to the environment, infrastructure and natural resources.

Before joining Castrén & Snellman I worked as a lawyer at another law firm and concentrated on real estate and construction related matters. Before my graduation I worked as a trainee in the real estate and environment team of another major law firm.

I graduated from the University of Helsinki in 2021. In addition, I studied energy and environmental law at the University of Aberdeen in Scotland for one semester.

Latest references

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
Merger of Oomi and Lumme Energia
We are acting as the joint legal advisor to Oomi Oy and Lumme Energia Oy in a transaction whereby Lumme Energia will merge with Oomi. As from the completion of the merger, the combined entity will be the largest electricity retail and service company in the Finnish market. In 2024, Oomi reported a turnover of EUR 373.9 million and had approximately 110 employees. Lumme Energia’s turnover for the same year was approximately EUR 314.6 million and it had approximately 50 employees. The transaction is primarily driven by the recent developments in the electricity market and the strategic goal to develop competitive products and services. Another key objective is to further enhance the customer experience, which is a shared value between the two companies. As a result of the merger, Lumme Energia’s customers will transfer to Oomi, and Lumme Energia will become one of Oomi’s shareholders. The completion of the transaction is subject to an approval by the Finnish Competition and Consumer Authority.
Case published 29.8.2025
Fortum – Acquisition of a project development portfolio for renewable power from Enersense
We are acting as a counsel to Fortum in a transaction in which Fortum is strengthening its renewable power project pipeline through the acquisition of a project development portfolio from Enersense. The debt-and-cash free purchase price is approximately EUR 9 million, with the potential for project-specific earn-outs subject to projects successfully reaching a final investment decision in the future. The transaction is subject to customary closing conditions and is expected to be completed during the first quarter of 2025. Fortum is a leading Nordic energy company with the purpose to power a world where people, businesses and nature thrive together. Fortum’s core operations comprise of efficient, CO2-free power generation as well as reliable supply of electricity and district heat to private and business customers. The company is listed on Nasdaq Helsinki. One of Fortum’s strategic targets is to develop at least 800 MW of ready-to-build onshore wind and solar projects by the end of 2026.
Case published 19.12.2024
Hanza AB – Acquisition of Leden Group
We acted as Finnish advisor to Hanza AB relating to its acquisition of all the shares in Leden Group Oy. Hanza AB is a Swedish mechanical engineering and electronics contract manufacturing company listed on the Stockholm Stock Exchange. Founded in 2008, the company has six manufacturing clusters in Sweden, Finland, Germany, Baltics, Central Europe and China and an annual turnover of approximately SEK 4.6 billion. Leden Group is a leading Finnish contract manufacturer specialising in sheet metal, machining and complex assembly. Leden Group has four production sites in Finland and one in Estonia and an annual turnover of approximately SEK 1.1 billion. 
Case published 13.12.2024
Fortum – Sale of recycling and waste business
We acted as the lead counsel to Fortum in a cross-border transaction in which Fortum sold its recycling and waste business. The business was sold to thematic impact investing firm Summa Equity through its portfolio company NG Group. The debt-free purchase price is approximately EUR 800 million.  Fortum’s recycling and waste business to be sold comprises municipal and industrial waste management and end-to-end plastics, metals, ash, slag and hazardous waste treatment and recycling services. These businesses are located in Finland, Sweden, Denmark and Norway and currently employ approximately 900 employees.
Case published 18.7.2024
Neoen – Sale of data centre
We advised Neoen Renewables Finland Oy, part of the French Neoen Group, in its sale of a data centre project to a consortium consisting of international data centre developers and operators. This marked Neoen’s first data centre development project in Finland. Founded in 2008, Neoen is one of the world’s leading independent renewable energy producers. The company operates in 15 countries. It develops, finances, builds, owns, and operates solar power plants, wind farms, and battery storage systems. Neoen Group is owned by global alternative asset manager Brookfield Corporation.
Case published 17.9.2026
Jolt Capital and Tesi – Investment in VEV
We advised Jolt Capital and Tesi in connection with their investment in VEV, a leading provider of commercial fleet electrification solutions. The investment, led by Jolt Capital with Tesi as co-investor, will support VEV’s next phase of growth and expansion across Europe. As part of the transaction, VEV became an independent company following the acquisition of Vitol’s stake in the business. Founded by Vitol, VEV provides integrated fleet electrification solutions combining fleet strategy, charging infrastructure, energy supply and operational services. Through its VEV IQ platform, the company supports more than 6,000 commercial electric vehicles across Europe and has been deployed across more than 600 sites spanning the transport, logistics and waste sectors. Jolt Capital is a private equity firm focused on growth investments in European deeptech companies. Tesi is a Finnish state-owned investment company that promotes Finnish business and economic growth through investments. We advised Jolt Capital and Tesi on the equity financing and structuring aspects of the transaction. International law firm Goodwin advised the investors on the acquisition of VEV.
Case published 10.9.2026
VR Group – Intellectual property matters
VR-Group Plc is a transport and logistics group owned by the Finnish State, operating passenger and freight rail transport in Finland with activities also in the Swedish market. VR Group provides passenger, logistics and maintenance services with over 160 years’ experience in developing responsible transport of the future. We advise VR Group in intellectual property matters as part of the company’s wider brand protection efforts. Our assignments have included advice on copyright, design rights and trademarks, focusing on the protection of the company’s visual identity – including its distinctive green colour – in connection with transport services as part of a comprehensive IP protection strategy. VR Group’s consistent brand building has also received recognition, including the Finland Chamber of Commerce’s Brand of the Year award in 2026. In the competition, brands were viewed comprehensively from various perspectives, including their story, strategic role, brand renewal ability and intellectual property protection. The jury found that VR had understood the importance of the protection of its brand as part of a comprehensive business strategy. 
Case published 9.9.2026

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