Bleaching events impacting coral reefs are increasing in frequency due to climate change. Renewable energy developer Ørsted seeks to combat these interlinked problems by launching a project to maintain healthy coral colonies on the foundations of offshore wind turbines.

Marine water temperatures are stable at offshore wind farms due to vertical mixing in the water column, preventing extreme temperature increases. The ReCoral by Ørsted initiative will exploit this temperature stability to limit the risk of coral bleaching by installing surplus indigenous coral spawn, collected as it washes ashore, on offshore wind turbines structures. Corals will be grown close to the water's surface to ensure sufficient sunlight.

Artist’s impression of future coral growth potential. Source: Ørsted

Ørsted researchers collaborated with private and academic partners to test the concept, and in 2021, successfully grew juvenile corals on underwater steel and concrete substrates at a quayside test facility for the first time. An offshore proof-of-concept trial is scheduled to begin in June at the Greater Changhua offshore wind farms in Taiwan to demonstrate the concept in open waters on four separate wind turbine foundations. If successful, opportunities for scaling up the initiative will be explored, with the goal of using additional coral larvae generated at offshore wind farm locations to restore and enhance threatened near-shore reef systems.