© 2020 Taylor & Francis Group, London.The patented Hull Vane, the energy saving appendage, is used to reduce the power need of the ships. It is a hydrofoil wing transversely fixed at the transom bottom of the ships. A negative pressure zone, which helps to reduce the stern wave, appears on the suction side of the Hull Vane due to the accelerated flow from the aft of the hull. In this study, the effect of the Hull Vane on the resistance components of the ship has been investigated in detail on the model scale by performing computational fluid dynamics (CFD) simulations. OpenFOAM (Open source Field Operation and Manipulation) has been used as a flow solver which is able to solve different types of fluid dynamics problems. In the scope of the numerical study the chord length of the Hull Vane has been changed to examine its effect on the total resistance. A significant 22.9% reduction on the total resistance has been observed on the subject ship as the result of the study.