Large-eddy simulation of wind farms and the impact of floating solar PV on wind power extraction

To address the limitations of expanding offshore wind farms in Belgium, the strategy of integrating floating solar photovoltaic (PV) systems and wind farms has emerged as a viable solution to increase power generation while using the same sea surface. In this study, large-eddy simulations (LES) of wind farms are performed through the ExaWind open-source codes, AMR-Wind and OpenFAST. First, the numerical framework is tested against experimental data and other LES solvers within the SWiFT Neutral Benchmark. Strong agreement is noted in horizontal wind speed and turbulence intensity, indicating that the atmospheric boundary layer is accurately captured. However, generator power and torque exhibit greater variability, with a tendency to overestimate compared to experimental measurements. Nevertheless, all simulated quantities remain within one standard deviation of the experimental data. The wake analysis further shows that the wake strength and shape are well reproduced, though the wake recovery is underestimated. These trends have been previously highlighted with similar solvers for the same benchmark, making the results consistent with the literature. Finally, the validated methodology is applied to assess the impact of floating solar PV panels, represented via an immersed boundary method, on the power extraction of a finite, aligned reference wind farm. A sensitivity analysis on the panels' layout reveals that their presence leads to an overall reduction in wind farm power output, primarily due to a slower wake recovery, which results from a weaker kinetic energy entrainment, and a higher velocity deficit.