تجزیه و تحلیل مشخصات فنی سیستم های تبدیل انرژی باد برای توسعه پایدار

Wind energy as a clean, environmentally friendly and cost effective renewable energy resource, is taken into consideration by many developed and developing countries as a promising means to provide electrical energy. In feasibility study stage of the wind energy systems, the sustainability analysis is one of the main issues that can assure the investors and stockholders to invest in this renewable energy. Since a system can be truly sustainable by achieving the energetic, ecological and economic sustainability, the present study will focus on the technical characteristics and performance analysis of the wind energy systems. The relations between reliability, availability, energy and exergy efficiency, risk management and the environmental impact of the wind energy systems are investigated in the context of this study. It is concluded that the wind characteristics data and the wind speed are the main effective parameters on its reliability and availability. It is also revealed that considering the system loss, exergy efficiency results of the wind energy systems are more reliable than the energy efficiencies. Due to avoid future failure of the systems, the causes of the failure are investigated and it was concluded that the structural failures caused by storms and strong winds are known as the most prevalent failures.

Renewable energy as the best substitution of fossil fuels is taking into account during the past decades to supply the worldwide energy demand. As the renewable energies are pollution-free, the produced electricity from them is called “green power” [1]. Among various renewable resources, wind energy as an abundant, free and environmentally friendly energy, experienced the fastest growing trend [2]. In order to evaluate the feasibility of wind power to provide energy, technical characteristics, energy and exergy analysis are studied. Generally, technical characteristics are studied in five aspects of reliability, maintenance requirements, availability, sustainability and environmental impacts. However, these aspects are interrelated, for instance, the maintenance and availability of the system have significant effects on its reliability. BoroumandJazi et al. [3] provide a comprehensive discussion on the technical characteristics of the renewable energy applications and their relation with system’s performances. The classification of the technical characteristics and their relations are illustrated schematically in Fig. 1.An alternative means to evaluate the performance of wind energy is exergy analysis. Applying this contemporary thermodynamic method to the system can give a more realistic view of its performance. Numbers of studies are conducted in performance evaluation of various systems using second law of thermodynamic, such as industrial boilers [4], gas turbines [5], and refrigeration cycles [6]. There are number of studies in literature, which computed the exergy efficiency of the renewable resources. A comprehensive review on application of the second law of thermodynamic in investigating the performance of the different solar systems is presented recently by Saidur et al. [7]. The performance analysis and technical characteristic investigation of a system play a crucial role in evaluating the renewable energy systems and lead to the development and the optimization methods of the systems. The present study reviews the existing surveys on the exergy analysis, sustainability, reliability and risk management of wind energy applications. In the context of this study, general characteristics of wind energy and wind turbine technologies are presented in Section 2. Moreover, the sustainability aspects of wind energy are investigated in Section 3. Furthermore, the reliability and availability of wind energy are studied in Section 4, which is followed by performance analysis, and risk management of the system in Sections 5 and 6, respectively. The environmental impacts of wind energy are studied in Section 7. Section 8 is a summary of analysis procedure of effective technical characteristic of wind energy system on its sustainability. The future direction in Section 9 will give some outlines to who are interested to continue their studies in this field. Finally, the conclusions of the study are presented in Section 9.

Following conclusions are made based on this study: I. A sustainable wind power system should be reliable, available, energetic, ecologic and economic sustainable system. II. To ensure the availability and reliability of the system, the wind speed data and wind characteristics are the main parameters to be analyzed. The Weibull probability density function and the artificial neural networks are the common tools that are applied for investigating the reliability and availability of a wind system. III. To ensure the energetic sustainability of the system, the performance analysis of the system based on the thermodynamic laws and its failure causes are studied. It is worth mentioning that among the energetic and exergetic analysis of a system, the results of exergy analysis are more reliable due to considering the loss of the system. A difference about 20–24% between the energy and exergy efficiencies is reported for low wind speeds, while it changes to 10–15% for high-speed turbine. IV. In order to consider the wind technology as an ecological sustainable technology, the effects of wind turbines on the birds and bats, their noise effect and visual impact should be decreased.