Navigating around offshore energy installations – “Do you know where your OREIs are tonight?”
by Joan Wenner 21 Jul 2024 05:55 UTC

Hugin USV anchored at Ørsted's Anholt wind farm © Maxwell Marine
Marking and lighting
While many mariners will navigate around wind turbines, others may decide to transit through them, which presents some unique challenges with marking and lighting notes maritime agencies.
Not only must the structures be well-marked to provide boaters ample time to avoid them, each turbine needs to provide orientation within the installation. In essence, the MaritimeCoastGuard Agency is meeting the challenge to light and mark the developments for those users of these areas.
Although offshore wind development is still in its relative infancy, the UK (along with the U.S.) has assisted with marking and lighting guidelines for several years through participation in the International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA) which published a guideline for The Marking of Offshore Man-Made Structures in 2021.
Offshore Renewable Energy Sites
The Maritime Coast Guard Agency reports new Offshore Renewable Energy Installations (OREIs) in UK waters, including wind, wave and tidal, must go through formal planning/offshore consulting processes. Applications must include a Navigation Risk Assessment which involves a consideration of the location, local navigational features, summer and winter boat traffic analysis and wide consultation between developer and navigation stakeholders.
OREIs must be lit and marked in a tical and logical manner, in accordance with international standards and not interfere with nearby marks/lights—and must be depicted on the nautical chart.
Marine Guidance Note (MGN) 654 was issued to developers in April of 2021. An amended Marine Guidance Note 372 was issued in November 2022 with advice to mariners operating in or near OREIs.
See MGN 654 at: www.gov.uk/government/publications/mgn-654-mf-offshore-renewable-energy-installations-orei-safety-response
See MGN 372 at: www.gov.uk/government/publications/mgn-372-amendment-1-mf-guidance-to-mariners-operating-in-vicinity-of-uk-oreis
Stay tuned and always remain cautious around these types of installations - day AND night.