Optimization Method of Wind Turbine Locations in Complex Terrain Areas Using a Combination of Simulation and Analytical Models

Once an area has been identified for a wind farm, the annual energy production of the farm is the most important quantity to obtain high exploitation efficiency. This quantity depends mainly on factors such as wind resource characteristics, type, number and arrangement of turbines. For areas with complex terrain, wind resource characteristics depend largely on terrain features, so the selection of turbine installation locations is very important. Because when the turbines operate, they will cause a wake effect that increases the turbulence of the flow behind. Therefore, it is necessary to find the optimal distance between turbines so that the annual energy production reaches the maximum value. This study presents a method to determine the optimal turbine locations when considering the correlation between wake loss and turbine space in the case of mountainous terrain. Firstly, a computational fluid dynamics model combined with a geographic information system are used to determine the 3-dimensional wind characteristics at specific locations. Secondly, a Jensen model is used to consider the wake effect according to the distance between turbines. Then, the the annual energy production values are determined through the analytical model. In addition, a comprehensive assessment of levelized cost of energy is also provided to confirm the practicality of implementing the optimization model. Finally, the optimal location configuration of the turbines is proposed. This method was tested and compared with a farm with sufficient data to assess reliability and then applied to an area in Ninh Thuan, Viet Nam. The results showed that the the annual energy production obtained from this farm can be up to 252.3 GWh (30 turbines) compared to 99.9 GWh (10 turbines), which is 2.5 times larger.