Evaluation of an Offshore Wind Farm by Using Data from the Weather Station, Floating LiDAR, Mast, and MERRA

Offshore wind energy is regarded as a key alternative to fossil fuels in many parts of the world. Its exploitation is based on the sound evaluation of wind resources. This study used data from a meteorological mast, a floating light detection and ranging (LiDAR) device, and the Modern-Era Retrospective Analysis for Research and Applications, a reanalysis data set established by the NASA Center for Climate Simulation, to evaluate wind resources of the Changhua-South Offshore Wind Farm. The average wind speeds evaluated at a height of 105 m in the studied wind farm were 7.97 and 8.02 m/s according to the data obtained from the floating LiDAR device and a mast, respectively. The full-load hours were 3320.5 and 3296.5 h per year when data from the LiDAR device and mast were used, respectively. The estimated annual energy production (AEP) with a probability of 50% (P-50) reached 314 GWh/y, whereas the AEPs with a probability of 75% (P-75) and with a probability of 90% (P-90) were 283 GWh/y and 255 GWh/y, respectively. The estimated AEP of P-75 was 90% of the AEP of P-50, whereas the estimated AEP of P-90 was 81% of the AEP of P-50. This difference might need to be considered when assessing the risk of financing a wind project.