Arenso Oy

Arenso Oy is a Finnish wind energy specialist that provides end‑to‑end services across the full life cycle of onshore and offshore wind farms, with a particular focus on the challenging conditions of the Baltic Sea and arctic environments. The company operates independently of equipment suppliers and contractors and supports customers from pre‑studies and project development through design, investment preparation, construction, optimisation, operation and maintenance, and ultimately dismantling and recycling of wind farms. Arenso’s team brings more than twenty years of experience from wind projects and has played a central role in designing and building Tahkoluoto, Finland’s first offshore wind farm and the world’s first offshore wind farm in frozen sea conditions, whose operation it currently manages while also developing the large‑scale Tahkoluoto Extension project. Founded in 2024 through the full demerger of Suomen Hyötytuuli Oy, Arenso initially took over the personnel and lifecycle responsibilities for the onshore and offshore portfolio of Suomen Hyötytuuli and Tahkoluoto Offshore Oy, delivering development, construction and operational services to these companies and their eight municipal‑utility owners. In 2026 part of Arenso’s operative management acquired the offshore wind business, including the Arenso brand, offshore team, foundation technology, bird‑radar expertise and research permits in Finland’s exclusive economic zone, with the new Arenso entity focusing on offshore technology and business development. The remaining service company for Suomen Hyötytuuli’s portfolio was renamed Hyötytuuli Services Oy. Arenso combines technical design, project management and operational optimisation with advanced environmental and monitoring capabilities. It has contributed to offshore foundation concepts, pioneered recycling of wind turbine blades in Finland, and developed and operated bird‑radar systems and shutdown‑on‑demand protocols to protect birdlife around offshore wind farms. The company applies these skills in customer assignments such as basic design of the 1.2 GW Saare‑Liivi offshore wind project in Estonia and early‑stage technical planning for Metsähallitus’ Ebba offshore wind project in the Bay of Bothnia, and leads a Baltic Sea Project‑funded initiative to create best‑practice guidelines for using bird‑radar data to minimise ecological impacts of offshore wind.