1 Copyright © 2014 by ASME WIND POWER OUTPUT PERFORMANCE HORIZONTAL AND VERTICAL AXIS WIND TURBINES FOR ISOLATED SMALL APPLICATIONS IN SAUDI ARABIA Luai M. Al-Hadhrami King Fahd University of Petroleum and Minerals Dhahran-31261, Saudi Arabia Shafiqur Rehman King Fahd University of Petroleum and Minerals Dhahran-31261, Saudi Arabia ABSTRACT The study evaluated the energy output and plant capacity factor of small wind turbines in the category of 3 – 10 kW rated power. The effects of hub height on energy output and the PCF have been studied. To achieve the set objectives, hourly average wind speed data measured at 10, 20, 30, and 40 meter and wind direction at 30 and 40 meter above ground level during July 01, 2006 to July 10, 2008 has been utilized. The highest percentage change in annual energy yield (AEY) was obtained for an increase in hub height from 20 to 30 m for both horizontal and vertical wind turbines used in this study. Horizontal axis wind turbines HAWT-1, HAWT-2, and HAWT-6; and vertical axis wind turbines VAWT-1, VAWT-2, and VAWT-4 are recommended for various ranges of loads. Horizontal axis wind turbines were found generally more efficient than the vertical axis wind turbine in the present case. In general, all the turbines showed a maximum increase in energy yield for an increase of 10 m in hub height from 20 to 30m and the annual mean energy yield usually followed the load pattern in the study area. Lastly, the mean turbulence intensity was always less than the value recommended in IEC64100-1 standard. KEYWORDS: Wind speed; wind anemometer; small wind turbine; turbulence intensity; wind power density INTRODUCTION Saudi Arabia is a vast country with total area of 2,149,690 sq km. It occupies most of the Arabian Peninsula, with the Red Sea and the Gulf of Aqaba to the west and the Arabian Gulf to the east. Saudi Arabia contains the world's largest continuous sand desert, Empty Quarter. The inhabitants are spread all over the land. Although most of the cities and towns are connected with electrical grid but some small dwellings in the north and south are fed by isolated diesel generating power plants. To connect all the localities with electrical grid is both time and money intensive; hence attempts are being made to diversify the means of power generation through wind and solar sources. The present paper is an effort towards understanding the usage of small wind turbines for small loads like battery charging, water pumping, street lighting, partially supplementing schools and gas stations, etc. The fast technological development and energy intensive life styles have resulted in tremendous increase in power requirements. Utilization of renewable energy resources has two fold benefits, one it reduces the dependence on fossil fuels and also supplies energy where there is no electrical grid. The widely used sources of clean energy include the wind, solar thermal, solar photovoltaic, hydro, geothermal, and biomass. Of these sources, wind has been adapted by industries and accommodated by individuals due to its availability, ease of maintenance, low cost of operation. The annual cumulative wind power installed capacity reached 282.587 GW by the end of 2012 compared to 238.050 GW in 2011, an increase of 18.71 %, (GWEC Ref. [1]). With a cumulative installed capacity of 75.324 GW, China remained the leader in wind power industry as of end of 2012. United States of America, Germany, Spain and India remained at 2 nd , 3 rd , 4 th , and 5 th place with total cumulated wind power installed capacities of 60.007 GW, 31.308 GW, 22.796 GW, and 18.421 GW; respectively by the end of 2012. The applications of small wind turbines, include heating greenhouses and residential buildings (Ozgener [2]), hydrogen production for upgrading bitumen from oil fields (Olateju and Kumar [3]), and water lifting (Abed [4]), to name a few. Lara et al. [5] evaluated a 3 kW wind turbine feeding a battery bank of 48 V/880 Ah by means of a non-controlled 6-pulse rectifier. The overall efficiencies showed a maximum of 17% of the wind energy to be available for water pumping. Nagai et al. [6] reported the performance of a 2 kW rated power wind turbine in terms of the functions of wind turbine rotational speed, generated outputs, and its stability for wind speed changes. The expected performance of the machine was confirmed under real wind conditions and the wind turbine showed a power Proceedings of ASME Turbo Expo 2014: Turbine Technical Conference and Exposition GT2014 June 16 – 20, 2014, Düsseldorf, Germany GT2014-26592