New Study Has Some Bad News for Wind Energy Advocates

The researchers looked at one area and ecosystem in particular — the North Sea — where the world’s largest offshore wind farm (OWF) opened earlier in 2022. Relying on modeling and simulations in order to see what the “systematic, large-scale, time-integrated response of the ocean to large OWF clusters” would be, the study’s authors found evidence that offshore wind power generation, supposedly great for the planet actually introduced factors that negatively impact sea life.

According to a summary of the study, researchers reported that their “results provide evidence that the ongoing off shore wind farm developments can have a substantial impact on the structuring of coastal marine ecosystems on basin scales.”

Now, for the science, as explained by the study’s authors:

The wind wake effect of offshore wind farms affects the hydrodynamical conditions in the ocean, which has been hypothesized to impact marine primary production. So far only little is known about the ecosystem response to wind wakes under the premisses of large off shore wind farm clusters. Here we show, via numerical modeling, that the associated wind wakes in the North Sea provoke large-scale changes in annual primary production with local changes of up to ±10% not only at the offshore wind farm clusters, but also distributed over a wider region. The model also projects an increase in sediment carbon in deeper areas of the southern North Sea due to reduced current velocities, and decreased dissolved oxygen inside an area with already low oxygen concentration.

[…]

In addition to impacts on the regional atmosphere, multiple physical, biological, and chemical impacts on the marine system have been identified. The under-water structures, such as foundations and piles may cause turbulent current wakes, which impact circulation, stratification, mixing, and sediment resuspension. Most studies conclude that the direct hydrodynamic consequences of the wind farm structures are mainly restricted to the area within the wind farms. However, some speculate also, that the cumulative impacts of an increasing number of offshore installations might result in substantial impacts on the larger scale stratification. Larger scale effects of offshore wind energy production, well beyond the wind farm areas, are introduced to the atmosphere by infrastructures above the sea level and the energy extraction itself. Atmospheric wakes appearing in the lee of wind farms extend on scales up to 65 km and beyond, depending on atmospheric stability, with a wind speed reduction of up to 43% inside the wakes leading to upwelling and downwelling dipoles in the ocean beneath.

More