How do offshore wind farms affect ocean ecosystems?

  • Some scientists say wind turbine areas are like artificial reefs, creating sanctuaries for marine life. But plenty of questions regarding their environmental impact remain.

November 22, 2017  Reach Deutsche Welle article here

The global shift to renewable energy is well underway, including large-scale deployment of offshore wind farms. There are already about 3,600 turbines operating along European coasts, with 14 more wind farms under development.

Even more wind energy is needed to meet the goals of the Paris climate agreement — but the push to boost European offshore wind power 40-fold by 2030 will change regional ocean ecosystems in profound and unexpected ways, according to researchers studying how the turbines affect the environment.

Most of the research stems from northern Europe, where offshore turbines have been operating since 1991. Scientists say this research can help shape plans for deploying offshore wind turbines in other parts of the world.

A recent study on the Mediterranean identified wind energy and wildlife hotspots, based partly on lessons learned in northern Europe. The science is also useful in places like Japan and the United States, where a boom in the development of offshore wind energy appears imminent….

….Harbor porpoises, for example, are especially sensitive to the frequencies generated by pile driving — the process of installing poles into the ocean floor for the wind turbine foundations. For up to six weeks, construction can push out marine mammals from large areas of their habitat, Todd said, explaining that offshore operators are bound to strict measures to try and ensure that marine mammals are not physically hurt…..once the installations are done, the animals return, she said, adding that scientists are seeing a similar process around some decommissioned oil and gas drilling platforms in the Gulf of Mexico. There, the US government is promoting the growth of productive ecosystems with the Rigs to Reefs program.

…The impacts of new offshore wind turbines should be considered together with effects from all other human activities, such as fishing, dredging, and oil and gas drilling, points out Bruna Campos, a marine and fisheries policy officer with BirdLife International, which has been watchdogging the wind industry for a while….

…authorities are making progress on large-scale plans that consider wildlife impacts — but the pressure to fast-track offshore wind means that they sometimes fall short of their legal obligations. As a result, conservation advocates have challenged a few wind energy projects in court.