Information for wind farm contractors

Wind farms affect both traffic and communications networks. Wind farms may affect the functionality of communications networks based on radio frequencies. Wind farms also form flight obstacles, which must be taken into account when assessing aviation safety. The construction of offshore wind farms must also observe any impact on maritime transport infrastructure. This page provides a more detailed description of the aforementioned impact of wind power plants and the procedures related to wind power.  

Wind farms and communications networks

A wind farm is an extensive construction project that may have minor effects on nearly all radio systems in its vicinity. Wind farms may dampen radio signals passing through the farm, or a high-power radio signal may be reflected from the structures of the wind farm and interfere with the reception of the signal. This is why wind power plant contractors must notify all known radio system operators in the vicinity of the construction site. The appropriate coordination range is 30 kilometres. The table below lists radio frequency users whose networks may be affected by wind farms:

Wind power operators should try to proactively resolve any challenges in using communications networks by working together with various parties to prevent any disruptions in the first place. If necessary, please contact the Finnish Transport and Communications Agency at radiotaajuudet@traficom.fi for further information on frequency users and masts in relation to constructing wind power.

Wind farms and aviation safety

Wind farms create flight obstacles, meaning that their impact on aviation and aviation safety must be examined. Section 158 of the Aviation Act (864/2014) requires advance flight obstacle permissions for erecting wind power plants, the cranes required to build them and any other tall structures required for the project. Please click here (External link) for more detailed instructions on acquiring flight obstacle permissions. The farms must be equipped with aircraft warning lights in accordance with the flight obstacle permit terms and conditions. 

Offshore wind power plants and observing maritime transport infrastructure

If an offshore wind farm is located close to channels or vessel traffic areas, it may cause disturbances to both vessel radar systems and to radar surveillance for vessel traffic management (VTS Finland) and result in danger to maritime transport.

The Finnish coast has more than 10,000 kilometres of public channels, stretching all along the coastline. In addition to this, approximately 100 fixed VTS radars are located in the shore areas. Due to the comprehensive channel and radar network, any planned offshore wind farms are usually located relatively close to channels or between channels and VTS radars. When planning offshore wind farms, you must take channel networks, aids to navigation and radar systems into account already in the early stages of planning, as they also impact the suitability of offshore wind farm locations from the point of view of seafaring. Constructing wind turbines in channels is forbidden, as this would prevent maritime transport in the designated area. Anchoring areas and approaches to channels are also important sections of the channel structure and fall under the same accessibility requirements. All merchant shipping channels in Finland are covered by traffic management, whose key observation method is radar. The uninterrupted operation of radars is vital. If an offshore wind farm causes any disruptions to radars, the disruptions must be compensated for with a new radar.

Offshore wind power projects that have not examined the impact of wind farms on shipping or maritime transport infrastructure may not contain plans to place wind turbines closer than 1.5 kilometres from the edge lines of channels or from anchorage areas in order to ensure navigation safety and uninterrupted traffic. In northern sea areas, winter navigation may require a distance exceeding 1.5 kilometres between wind turbines and channels or anchorage areas to ensure proper operating conditions for vessels. Traficom may assess the required distance more closely once the impacts of the wind farm on, for example, maritime positioning and radar systems, navigation safety and channel use have been determined. In the exclusive economic zone, wind turbines must be located at least 1–3 nautical miles from traffic separation schemes, vessel traffic areas in the open sea and approaches to channels. The required distance in a specific region must be determined case by case based on, for example, the location of the project area, ensuring proper operating conditions for winter navigation, analyses regarding the project, and risk analyses by maritime operators.

You should contact Traficom and VTS Finland concerning the details of the appropriate analyses and reports already during the initial phase of project planning. This also applies to sea areas suited for wind farms from the point of view of maritime transport.

Further information:

Offshore wind farm projects: jani.koiranen@traficom.fi, Finnish Transport and Communications Agency

Frequency usage and masts: radiotaajuudet@traficom.fi, Finnish Transport and Communications Agency

Flight obstacle permits: https://www.traficom.fi/en/services/apply-obstacle-permission (External link)

The impact of wind farms on radio systems and the reduction of adverse effects

Instructions on constructing a wind farm close to traffic routes (External link) (available only in finnish)