Offshore wind energy is integral to Europe’s climate and energy goals, with plans to install 500 GW of capacity by 2050. However, wake effects, which involve reductions in wind speed and energy yield caused by upstream turbines, pose a significant efficiency challenge, particularly in dense wind farm clusters in the North Sea. This study examines the implications of large-scale wakes, focusing on cross-border effects and mitigation strategies. Through an assessment of the kinetic energy budget of the atmosphere (KEBA), it identifies wake-induced yield reductions of 30% for the German Bight in the North Sea, with half of these being attributed to the cross-border accumulation of wakes. The findings demonstrate that redistributing wind farm capacities across borders could reduce wake losses to 18%, thereby enhancing energy yield. This could prevent the equivalent of about 8 GW offshore wind generation capacity being lost due to wakes and reduce the levelised cost of electricity. This study highlights the importance of cross-border collaboration and sea basin wide planning to optimise wind farm placement, enhance production efficiency, and ensure the economic viability of offshore wind energy.