Energy production and inter-farm wake losses in future North Sea wind farms

Abstract The deployment of new wind farms in the North Sea is an essential part of Europe’s transition to low-emission energy sources. Here, we use the mesoscale climate model COSMO-CLM to simulate the energy production of a realistic 92 GW wind farm expansion scenario and compare it with that of the wind farm distribution in 2024. The simulations indicate that added inter-farm wakes would cause the annual energy production of 25 out of 69 operational wind farms to decline by over 5%, with 13 of them experiencing reductions exceeding 10%. These annual losses are composed of intermittent wake periods characterized by large production deficits. For instance, the planned Princess Elisabeth zone in Belgian waters is expected to reduce the output of the existing Belgian wind farm cluster by more than 15% during one out of every five 24 h periods with high production potential ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mrow> <mml:mover> <mml:mi>V</mml:mi> <mml:mo stretchy="false">¯</mml:mo> </mml:mover> </mml:mrow> <mml:mo>&gt;</mml:mo> <mml:mn>9</mml:mn> </mml:mrow> </mml:math> ms −1 ). Despite these enhanced inter-farm interactions, we find that the overall capacity factor over the basin increases by 1.6%pt after expansion due to the deployment of next-generation turbines and installation at low capacity densities in high-resource zones. However, negative impacts are highly region-dependent and many wind farms may face substantial losses. Although more validation studies are recommended to further constrain the uncertainty on the presented results, this work demonstrates the need for a coordinated wind farm expansion strategy, especially because spatial constraints are expected to intensify on the path to surpassing 200 GW of capacity in the North Sea by 2050.