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
Shareholders – Sale of the Suomen Autohuolto Group
We advised the shareholders of Suomen Autohuolto Oy in connection with the sale of the company’s entire share capital, to SAKA Finland Group Oy. Suomen Autohuolto Group is one of Finland’s largest companies specializing in brand-specific automotive maintenance and has locations in Oulu, Tampere, and from July, also in Järvenpää. The transaction is subject to final approval by the Finnish Competition and Consumer Authority (KKV).
Case published 26.6.2026
AI training
Natural Resources Institute Finland – AI training
We delivered two tailor-made AI workshops for the lawyers at the Natural Resources Institute Finland (Luke). We discussed the AI revolution and its impact on lawyers’ ways of thinking and working, and left the participants with practical solutions for enhancing and streamlining their work with Legora. Our AI-specialist lawyers prepared use cases tailored to Luke and the needs of public administration, which Luke received for its own use following the workshops. These use cases covered topics such as: utilising legal sources and the organisation’s own data to maximise AI results building and leveraging AI workflows AI-enhanced contract drafting based on a large volume of documents. The workshops sparked wide-ranging discussion on the role and benefits of AI in legal work. Participants appreciated how clearly and comprehensively our experts were able to present the nature and benefits of AI specifically within a legal context. ‘The workshops provided excellent support for Luke’s goal of leveraging AI responsibly and gave us concrete and ready-to-use practical takeaways,’ says Hannu Laitinen, Luke’s Senior Vice President, Administrative Affairs.
Case published 26.6.2026
Finnish Construction Management Consultancy — District Court Dismisses charge in occupational safety offence case concerning a safety coordinator
We successfully represented a Finnish construction management consultancy and a safety coordinator employed by the company in criminal proceedings concerning an alleged occupational safety and health offence. The prosecutor sought a penalty for an alleged breach of occupational safety regulations. The charge arose from a fall accident at a construction site where our client acted as the safety coordinator appointed by the developer. We assessed the scope of the safety coordinator’s duties in relation to the responsibilities of the main contractor, as well as how our client had fulfilled their obligations in practice. We demonstrated that our client had acted with due care and in full compliance with their duties throughout the planning, preparation and execution of the construction project. The District Court of Eastern Uusimaa dismissed the charge against our client. The Court held that our client, in their capacity as safety coordinator, had duly fulfilled the occupational safety obligations incumbent on the developer during the planning and preparation phases of the construction project and had not been aware of the fall protection deficiency identified at the site. The judgment is final insofar as our client is concerned.
Case published 22.6.2026

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