ارزیابی پتانسیل باد در استان کرمانشاه

به منظور ارزیابی پتانسیل بادخیزی در محدوده استان کرمانشاه داده‌های سرعت و جهت باد (دوره آماری 2009 تا 2013)، مدل رقومی ارتفاع و کاربری زمین اخذ شد. نقشه‌های منحنی میزان منطقه با فاصله های ده متر، زبری سطح زمین و موانع موجود در ایستگاه‌ها برای تولید اطلس باد آماده شد. ویژگی‌های باد در ایستگاه‌های هواشناسی تولید و بررسی شدند؛ سپس پتانسیل باد با کمک پارامترهای میانگین چگالی توان باد، محتمل‌ترین سرعت باد و سرعت باد بیشینه تولید انرژی در شرایط مشابه برای محدوده ایستگاه‌‌ها (ارتفاع 40 متری از سطح زمین و زبری سطح 0.03 متر) ارزیابی شد. مقایسه ویژگی‌های برآوردشده باد در ارتفاع 40 متری از سطح زمین برای زبری سطحی کلاس یک (0.03 = z0 )، در محدوده ایستگاه‌های مورد بررسی نشان داد که میانگین سرعت باد به‌ترتیب در محدوده ایستگاه‌های گیلان‌غرب (جنوب غرب استان) و تازه‌آباد (شمال غرب استان) بیشترین و در محدوده ایستگاه‌های کنگاور (شرق استان) و سرپل‌ذهاب (غرب استان)، کمترین مقدار را دارد؛ همچنین با توجّه به پارامتر k ویبول مشخّص شد که رژیم بادی در ایستگاه‌های تازه‌آباد، سومار (جنوب غرب استان) و گیلان‌غرب یکنواخت‌تر و در ایستگاه‌های کنگاور و روانسر (شمال استان) نامنظّم‌تر از دیگر ایستگاه‌ها است. در ایستگاه‌های روانسر و کنگاور نبود وزش باد، محتمل‌ترین پیشامد است؛ همچنین در ایستگاه‌های سرپل‌ذهاب و اسلام‌آباد غرب (جنوب استان) نیز محتمل‌ترین سرعت باد بسیار پایین و کمتر از یک متر بر ثانیه است. درحالی که محتمل‌ترین سرعت باد در ایستگاه‌های تازه‌آباد (m/s5.72)، گیلان‌غرب (m/s5.61) و سومار (m/s4.91) به‌ترتیب بالاترین مقادیر را دارند؛ بنابراین باوجودی که ویژگی‌های سرعت باد نظم مکانی مشخّصی نشان نمی‌دهد، به این صورت که گاه ایستگاه‌هایی با فواصل کم تفاوت‌های زیادی دارند که ناشی از اهمّیت تاثیر عوامل محلّی و ریزمقیاس و پیچیدگی‌های منطقه است؛ به طور کلّی می‌توان گفت که نیمه غربی استان نسبت به نیمه شرقی پتانسیل بادخیزی بالاتری دارد.

The Assessment of Kermanshah Wind Potential

We gathered wind data (20092013), Digital Elevation Model and Landuse maps to assess wind potential. Topographic maps of the area with contour distances of 10 meters, surface roughness and obstacles in the stations were prepared to produce wind atlases. Then wind potential was calculated and evaluated using parameters including mean wind power density, most probable and maximum energycarrying wind speed in 40 m AGL and 0.03 m surface roughness conditions. The comparison of wind properties in studied sites for 0.03m surface roughness and 40 m AGL conditions showed that mean wind speed is the highest in Gilanqarb and Tazehabad and the lowest in Kangavar and Sarpolzahab respectively. Besides, the investigation of shape reveals that wind speed is more uniform in Tazehabad, Somar and Gilanqarb, while it is less uniform in Kangavar and Ravansar. Most probable wind speed equals to 0 in Ravansar and Kangavar. Moreover, it is very low (less than 1 m/s) in Sapolzahab and Eslamabadqarb ,while it is the highest in Tazehabad (5.72m/s), Gilanqarb (5.61 m/s), and Somar (4.91 m/s). Although there is no notable spatial pattern for wind speed in Kermanshah province due to topographical complexity, sites with high wind energy potential is more frequent in west of this province (such as Tazehabad, Gilanqarb and Somar) compared to the east of it. Thus, the west of this area has more potential to use wind energy in general.Extended Abstract1IntroductionRecently, the development of renewable energy in order to replace fossil fuel energy generation has been identified as a key strategy to mitigate climate change which is now a standard objective of national and international climate and energy policies. Furthermore, the growing use of renewable energy not only enhances the mitigation of global warming but also serves to meet future energy demand. Among the various types of available renewable energy in the country, wind energy is currently one of the fastest growing, most commonly used and commercially attractive renewable sources for generating electricity. Wind resources present a promising option to be integrated with the conventional energy sources to match the increased demand of electricity. Since there has not been no comprehensive wind potential study so far, in Kermanshah province, it is necessary to pay this important subject to reply for increased demand of electricity.   2Materials and MethodsWe gathered wind data (20092013), Digital Elevation Model and Landuse maps to assess wind potential. The present study assesses the average of monthly wind speed, hourly wind speed, directional wind speed, wind rose, stability frequency, weibull distribution fit, and cumulative distribution curves in all synoptic stations. Applying parameters like mean wind power density, most probable and maximum energycarrying wind speed, wind potential was calculated and evaluated in 40 m AGL and 0.03 m surface roughness conditions. 3Results and DiscussionThe findings show that annual mean wind speed in Sararood, Gilanqarb, Somar and Tazeabad is highest, while it is lowest in Sarpolzahab, Kangavar and Ravansar stations. Generally, average wind speed is higher in warm months than cold months in all station except for Tazehabad station. The assessment of mean annual diurnal profile of mean wind speed shows that it follow diurnal heating in most of stations and months. However, it is not true for Tazehabad, Gilanqarb and Somar stations completely, where diurnal profile of mean wind speed affected by landform mostly. The coefficient of variation of mean monthly wind speed is higher in November, December, January or February in most stations and it also is lower in warm months of spring and summer seasons. Besides, the highest variation of mean monthly wind speed has seen in Ravansar, Kangavar, EslamAbad, Sonqor and Javanrood, while the lowest is seen in Tazehabad, Somar and Qasreshirin stations. The wind direction frequencies exhibit W pattern as the most frequent or second for the all stations, and also N and NE patterns as the lowest frequency directions in most stations. There has not been any spatial pattern for wind speed in the study area, so that close stations are different in wind speed properties which is due to local and micro scale factors importance and topographical complexity in this region.The comparison of wind properties in studied sites for 0.03m surface roughness and 40 m AGL conditions showed that mean wind speed is the highest in Gilanqarb and Tazehabad and the lowest in Kangavar and Sarpolzahab respectively. Besides, the investigation of shape reveals that wind speed is more uniform in Tazehabad, Somar and Gilanqarb, while it is less uniform in Kangavar and Ravansar. In spite of lower mean wind speed in Ravansar than Tazehabad and Gilanqarb, this site has more mean wind power density, which is due to more occurrence of high speed winds, leading to more energy potentially. However, this high mean wind power density cannot lead to high energy production for two reasons. First, high wind occurrence irregularity and second, not increasing or even reducing the amount of energy generated by turbines from a certain wind speed. This is true somewhat for Eslamabad station, too. Thus mean wind power usage alone will be misleading to investigate wind potential and it is necessary to use this parameter with another parameter such as wind uniformity. Most probable wind speed equals 0 in Ravansar and Kangavar while it is very low (less than 1 m/s) in Sapolzahab and Eslamabadqarb. Moreover, it is the highest in Tazehabad (5.72m/s), Gilanqarb (5.61 m/s), and Somar (4.91 m/s).4ConclusionAlthough there is no notable spatial pattern for wind speed in Kermanshah province due to topographical complexity, sites with high wind energy potential is more frequent in west of this province (such as Tazehabad, Gilanqarb and Somar) compared to the east of it. Thus, the west of this area has more potential to use wind energy in general.