<p>The horizontal axis wind turbine is a technologically advanced energy extraction device that can capture the power of wind energy, which is one of the renewable energy sources that is growing exponentially. This study focuses on analysing the performance of HAWTs for offshore wind conditions. Computational fluid dynamics is used to measure the effect of the blade tip devices, specifically split-winglets at varying wind speeds. It is concluded that adding a split-winglet to the blade increased its performance by 7% at wind speeds of 6, 8, and 10&#xa0;m/s. The influence of varying the split-winglet cant angles is also investigated and found that a cant angle of 45° is optimal. The performance of the blade is decreased on increasing the cant from 45° to 60°. The study further investigated the aeroelastic effect of the blade after tip addition using the one-way FSI methodology. The aeroelasticity involves the study of the mutual interaction between the aerodynamics and structural dynamics, where structural deformation alters the airflow around the blade, and the resulting aerodynamic forces further influence the structural response, creating a continuous feedback loop. This is performed for varying wind speeds for the base blade and optimum split-winglet configuration of 45° for two material properties. The results showed that adding split-winglet to the base blade increased the maximum deformation of the blade. The study indicates that split winglet blades have the potential to enhance the aerodynamic and aeroelastic performance of HAWTs under offshore wind conditions. However, it is important to limit the deformation of the blade to prevent collisions of the blade with the tower.</p>