Suitability of utilizing small horizontal axis wind turbines for off grid loads in eastern region of Saudi Arabia

Small wind turbines of 1-3, 5-10, and 15-20kW rated powers are used to find out suitable and efficient turbines for power generation in the eastern region of Saudi Arabia. Additionally, the effect of hub height on energy output and the plant capacity factor is investigated to recommend an optimal hub height to be used in the present case. To achieve the set objectives, hourly mean wind speed data measured at 20, 30, and 40m and wind direction at 30 and 40m during 13 September 2005 to 9 May 2010 have been utilized. The annual mean wind speed values were 5.73, 5.34, and 4.75 m/s at 40, 30, and 20m with north-north west (NNW) prevailing wind direction. An increase of about 20.7% was estimated in wind speed measured at 40m compared to that at 20 m. Wind turbines Fortis Passat-1.4kW, Fortis Montana-5.8kW, Fortis Alize-10kW, and CF20-20kW with annual energy and plant capacity factor of 7.015MW h and 57.2%, 25.955MW h and 51.08%, 42.603MW h and 48.63%, and 54.674MW h and 31.21% were the most efficient turbines for the chosen location, respectively. Highest percentage increase in annual energy yield was obtained for a mere change of 5m from 15 to 20m in hub height in the present case study. The next best annual energy yield was obtained while increasing hub height from 20 to 30 m.