| چکیده انگلیسی مقاله |
Extended Abstract
Introduction:
Energy is one of the most important and vital socio-economic inputs of development (Keyhani et al., 2010). Expansion of industries, ever-increasing population and limitation of non-renewable resources have intensified the tendency to study renewable energies especially wind energy. Feasibility study is the first step on the establishment of wind farms.The world's wind energy production capacity reached to 435 Gigawatts in 2015, but still it is only around 7% of the potential energy production capacity of this huge clean energy source. At present, China, United states, Germany, India and Spain are the leading countries in the use of wind energy in the world. China alone obtains about 50% of her energy from wind powers. Meanwhile, in 2015, Iran produced only 117 megawatts which is about 0.03% of total energy obtained from wind in the world (World Energy Council, 2016: 57). Iran's vast area with relevant climate variability has a higher potential capacity than what is now being exploited. Therefore, a correct understanding of the temporal-spatial pattern of wind speed and its annual and intra-annual variability is the first step to focus on the areas prone to wind power generation in the country. The main purpose of this study is to investigate and feasibility of winter wind energy in Ardabil.
Materials and methods:
In the present study, 3-hourly data of Ardabil synoptic station were used in the period of 1995 to 2004. In order to determine potential wind energy, wind velocity and wind direction data as well as temperature in winter in the hour 00, 03, 06, 09, 12, 15, 18 and 21 were gathered. Usually, wind velocity and direction are recorded at a height of 10 meters above the ground. Then, its wind rose and wind energy were drawn using WRPLOT version 7.0. In order to determine long-term changes of the average wind velocity, linear regression method has been used. International Renewable Energy Agency in collaboration with the Technical University Denmark (DTU) have presented the world's most complete wind atlas. In this research, information and maps of the World Wind Atlas were used. The latest atlas uses ERA5 dataset of European Center for Medium-Range Weather Forecasts (ECMWF) for the simulations in period 2008-2017. In the present research, data gathered in 6 points including Ardabil's synoptic station and 5 other points (in the windy areas in the county) have been analyzed using the information of this atlas.
Results and discussion:
In December and January, wind velocity at 12:00 UTC in Ardabil synoptic station during the studied period, was greater than or equal to 4 m/s on 82% of the days while it is the same on all days (100%) in six months of the year. Meanwhile at 15:00 UTC more than 60% of the days and at 9:00 UTC more than 65% of the days during the year the status was like the same too. In other words, in three months of the year, it is possible to extract Potential energy in a great number of the hours during days and nights in this station. In other months, the feasibilty remains in one third of the hours of the day and night. Results shows that in all months, there have been significant changes in the trend of wind velocity in Ardabil station. Also, using the Global Wind Atlas (GWA), average wind velocity was extracted at 10 and 50 meters in the area around Ardabil. The area of Ardabil can be divided into two halves, north-west and south-east. the south-east part of the city have a more significant wind velocity. It is due to the fact that some areas of the city have had high average annual wind velocity (2008-2017). It must be noted that in the two studied parts, 6 areas were selected in the city and analysis were done. The average power density for 10% of the selected areas had the highest values (e.g., in Heer village, Dojagh village and Foladloy were 896 w/m2, 720 w/m2 and 611 w/m2 respectively. While average value of power density for Ardabil, Balghou and Kalkhoran were 348, 357 and 331 w/m2, respectively.
Conclusion:
In December, January and February, energy is possible to expolite in the most hours day and night at this station, while in other months, only durind a third of the hours of days and nights it is available. In the most months of the year, there have been significant positive changes in trend of wind velocity in Ardabil synoptic station. The biggest changes were in January, which is increased more than 4 m/s comparing to the average wind velocities in a 36-year duration of the analyzed data. Based on the results extracted from Global Wind Atlas in the 6 studied points in the windy areas around Ardabil, differences in wind velocity, prevailing wind direction, peak hours of wind and the behavior of these variables in the different months of the year were determined. The lowest wind velocity and potential energy density is in Ardabil (near synoptic station) and the highest is in an area in Heer village in the southeast of Ardabil. According to the classification of wind based on International Electronic Commission, Heer district can be categorized in the second class, while the other two stations are put in the third class. Since the minimum velocity required for installing commercial turbines is 6 meters per second and for starting small turbines is about 4 meters per second, it is suggested to start turbines in Ardabil, Balgho district and Kalkhoran. Feasibility studies should be carried out on small farms in Heer, Dojagh, and Foladloy to set up commercial farms.
Keywords: feasibility, Ardabil, Global Wind Atlas, trend. |