화학공학소재연구정보센터
Desalination, Vol.209, No.1-3, 199-208, 2007
Wind resource assessment of eastern coastal region of Saudi Arabia
Depleting oil and gas reserves, combined with growing concerns of global warming, have made it inevitable to seek energy from renewable energy sources such as wind. The utilization of energy from wind is becoming increasingly attractive and is being widely used/disseminated for substitution of oil-produced energy, and eventually to minimize atmospheric degradation. Quantitative assessment of wind resource is an important driving element in successful establishment of a wind farm/park at a given location. More often than not, wind-energy resources are relatively better along coastlines. In the present study, hourly mean wind-speed data of the period 1986-1997 recorded at the solar radiation and meteorological station, Dhahran (26 degrees 32' N, 50 degrees 13' E, eastern coastal plain of Saudi Arabia), have been analyzed to present different characteristics of wind speed in considerable depth such as: yearly, monthly, diurnal variations of wind speed, etc. The long-term monthly average wind speeds for Dhahran range from 4.2-6.4 m/s. More importantly, the study deals with impact of hub height on wind energy generation. Attention has also been focussed on monthly average daily energy generation from different sizes of commercially available wind machines (150, 250, 600 kW) to identify optimum wind machine size from energy production point of view. It has been found that for a given 6 MW wind farm size, at 50 m hub height, cluster of 150 kW wind machines yields about 48% more energy as compared to 600 kW wind machines. Literature shows that commercial/residential buildings in Saudi Arabia consume an estimated 10-40% of the total electric energy generated. So, concurrently, as a case study, attempt has been made to investigate/ examine the potential of utilizing hybrid (wind+diesel) energy conversion systems to meet the load requirements of hundred typical 2-bedroom residential buildings (with annual electrical energy demand of 3512 MWh). The hybrid systems considered in the present case-study consist of different combinations of wind machines (of various capacities), supplemented with battery storage and diesel back-up. The deficit energy generated from the back-up diesel generator and the number of operational hours of the diesel system to meet a specific annual electrical energy demand of 3512 MWh have also been presented. The diesel back-up system is operated at times when the power generated from wind energy conversion systems (WECS) fails to satisfy the load and when the battery storage is depleted. The evaluation of hybrid system shows that with seven 150 kW WECS and three days of battery storage, the diesel back-up system has to provide 17.5% of the load demand. However, in absence of battery storage, about 37% of the load needs to be provided by the diesel system.