A parametric study of small-scale offshore vertical axis wind turbines: unlocking potential in low wind profile regions

In recent decades, wind turbines have emerged as substantial renewable energy technology, particularly for offshore applications. However, the utilisation of conventional wind turbine in regions characterised by a low wind speed profiles, such as Malaysia, remains limited. Therefore, this study addresses the gap by developing an unconventional small-scale Vertical Axis Wind Turbine (VAWT) provision for offshore application in Malaysia's low wind speed regions. The study commenced with a wind feasibility analysis which aimed to determine the viable range of offshore wind speeds prior conducting wind tunnel tests. The VAWT model was designed using Solidworks software, fabricated using a 3D printer and tested in the National Defence University of Malaysia (UPNM) wind tunnel lab facilities. Through a systematic analysis and optimisation of blade diameters, stages and angles using Taguchi method, this study aimed to enhance the wind turbine performance in terms of power coefficient (Cp) and tip speed ratio. The result highlighted the pivotal role of blade diameter and the number of stages as a key design factors for VAWT, with the optimal configuration of blade diameter of 16 cm, a single stage and Angle of Attack (AoA) set at 7˚. This configuration exhibited a remarkable Cp value of 0.622, signifying the power output efficiency of small-scale VAWT. Meanwhile, variations in AoA were found to be the least significant design factor, as all models demonstrated peak Cp values corresponding to wind speeds. Thus, these findings show the key design considerations for small-scale VAWT in low wind profile regions as well as contributing valuable knowledge for the sustainable development of wind energy in Malaysia.