Understanding Wind Power Systems

Abstract

All of the above statements represent prominent objections to wind power development. For the most part, these statements are premised upon small truths that have been exaggerated by wind power opponents in order to generate public opposition. The intent of this chapter is to try and separate fact from fiction in order to give the reader a better technical understanding of the true hurdles faced by nations that embark on ambitious wind power development programs. Although a technical understanding of wind power systems is not necessary to understand the case studies presented in this book, enhanced technical understanding will help the reader better understand the possibilities and limitations of the technology. This chapter begins by describing the basic components of a wind power system before exploring how technical choices made in regard to system components and site location influence generation costs. From this technical foundation, the discussion will shift to the stochastic (fluctuating) nature of wind power and examine existing solutions for smoothing power fluctuations. This will provide the reader with a better understanding of the potential of wind power systems to replace fossil fuel electricity generation technologies. In concluding sections of this chapter, an attempt will be made to separate truth from fiction in regard to community and environmental impacts commonly attributed to wind power systems. Hopefully, by the end of this chapter, the pros and cons associated with wind power development will be better understood. There are basically two main wind turbine designs—vertical axis and horizontal axis. Vertical axis wind turbines (VAWT), which can resemble egg beaters placed on towers, are not widely used for electricity generation, so this section will focus on the main components of horizontal axis wind turbines (HAWT). The main components of a wind turbine includes the rotor blade; the nacelle (which houses the gearbox, generator, and yaw motor); the tower upon which the wind turbine is placed; the foundation which anchors the tower to the ground; the control system and transformer (usually located at the base of the tower), which transforms the collected energy into electric current that can be delivered to the electricity grid; and the electrical conduits that connect the wind turbine to the electricity grid.