Offshore wind energy is rapidly expanding across the Baltic Sea. Developments like these are crucial to a green energy transition gathering pace, but ensuring it doesn’t come at a cost for local and migrating birdlife isn’t easy.
Thankfully, plenty of conscious energy providers and wind farm operators are up for the challenge. Arenso Oy, a Finnish pioneer in offshore wind, is one of them.
A longstanding partner of Robin Radar, Arenso Oy has launched a new initiative to integrate avian protection directly into offshore wind development. They’ll do it by harnessing a decade’s worth of bird radar and observational data collected at the Tahkoluoto offshore wind farm.
Tahkoluoto offshore wind farm, owned by Suomen Hyötytuuli Oy and operated by Arenso Oy, have become a shining example of how radar technology can assess the impact of wind energy on bird populations in marine environments.
The initiative, supported by a €65,000 grant from the Baltic Sea Project, now aims to set a new industry benchmark backed by a decade of data.
Putting bird conservation on the radar
The use of bird detection radars in wind farms isn’t new, but for many developers and regulators, questions remain unanswered about how best to leverage them. Now, the Arenso Oy project is offering those answers for Finnish developments. Through practical experience and observational data, light has been shed on key areas, such as:
- Best practices for implementing bird radar systems in offshore wind farms specific to the Finnish marine context.
- How long-term radar data can be used effectively in environmental planning.
- The strengths and limitations of radar compared to traditional observation methods.
- How radar systems can be used to trigger real-time turbine shutdowns to prevent bird collisions.
“Bird radar monitoring provides real-world value for the Baltic Sea’s sensitive birdlife,” says Petteri Mäkelä, Environmental Manager at Arenso Oy. “The data enables developers to avoid placing turbines in critical bird habitats and to implement dynamic shutdown protocols when birds are on a collision course. It also streamlines permitting by offering standardised, transparent environmental assessments.”
Copyright: Arenso Oy / Petteri Mäkelä
Protocols built upon a decade of data
Though numerous Finnish offshore wind farm developments are currently underway, Tahkoluoto has Finland’s only operational offshore wind farm. It’s also the first equipped with bird radar and to initiate shutdown on demand (SDOD).
For almost a decade, in combination with visual observation, the radar system has continuously monitored the site and its surroundings to establish a rich dataset on migratory routes, feeding grounds, and interactions with turbine structures.
Robin VP Wind and Environmental Practice, Sibylle Giraud, explains why long-term monitoring like this is tremendously valuable: “To plan a wind farm that takes the unique life and patterns around it into account, we must start from scratch. New data is gathered to identify times or locations where birds could be more vulnerable, but it doesn’t stop there.
“It’s important to continue monitoring bird activity after construction. Far-reaching impacts are extremely hard to predict, so we need to keep gathering data to identify them over time. That’s why long-term monitoring is so valuable in understanding how best to protect birds at wind farm sites.”
Copyright: Arenso Oy / Petteri Mäkelä
From observation to action
The approximately 7-month project, run in collaboration between Arenso Oy and One Planet Oy, is structured in three phases:
Assessment of bird radar use: A comprehensive study on how radar systems can support avian impact assessments and collision avoidance in offshore environments.
Guidelines and best practices: A detailed document outlining effective radar deployment, data interpretation, and limitations specific to the Finnish marine context.
Training and knowledge sharing: A practical training package for developers, authorities, and stakeholders to ensure widespread adoption and consistent methodology.
With these outputs, wind developers and regulators can integrate radar-based monitoring into planning, permitting, and operational procedures, enhancing both environmental protection and project efficiency.
Amanda Pasanen, Senior Advisor at One Planet, echoes the importance of radar-based decision-making: “Offshore wind is growing globally, but we still have limited knowledge about its ecological impacts in the Baltic. This project brings invaluable new data to the table and ensures that the green transition supports and preserves biodiversity.”
Researching remote ecosystems
Tahkoluoto offshore wind farm is one of many sites to demonstrate how bird radar is fast becoming a strategic asset for responsible offshore wind development.
Researching the effects of human activities and infrastructure on the natural world in this way is integral to setting up protocols that protect it. Sibylle Giraud said: “I joined Robin in 2018 to expand our scope and create a team fully focused on the wind and environmental segment.
“It’s been an extraordinary journey seeing our systems gradually deployed worldwide. What I love the most is the passion within the industry to keep finding ways to protect birds.
“Protecting the balance between human society and the natural world is becoming even more of a challenge. However, the pace of innovation is accelerating in every corner of the planet. Radar application is surging in important projects, just like this one.”
Copyright all photos in this article - Arenso Oy / Petteri Mäkelä