电力书籍electric power generation—ch9.pdfVIP

9 WIND POWER GENERATION 9.1 INTRODUCTION TO WIND Wind power has been utilized by mankind since historical times. It has brought distant lands together, from the early days when the Greeks set sail on their ventures to later when Colombus “discovered” America. The famous character “Sancho Panza” made windmills immortal in literature. Of late, windmills have been getting increasing attention on account of wind energy being available “free” of cost and also on account of being the most nonpolluting source of electricity. On the electricity front, it started with a wind turbine driving an electricity generator, mainly an induction motor, which is universally available. The output ratings were minuscule: a few hundred watts. Today, it is entering into the club of megawatt-scale electricity producers. Kriegers Flak, an island located in the Baltic Sea between Sweden, Denmark, and Germany, is expected to fully commission its wind farm rated at 630 MW by 2010. The latest rates of growth are striking. In Europe, wind farm installations grew at a rate of 38% during 2007, compared to 19% during 2006. By 2007, total installed wind power capacity there stood at 67 GW. Germany, Denmark, and Portugal were promi- Electric Power Generation. By Digambar M. Tagare 173 Copyright © 2011 the Institute of Electrical and Electronics Engineers, Inc. 174 WIND POWER GENERATION nent. In the United States, total wind farm capacity stood at 11 GW in 2007. It is grow- ing fast in China, India, and many other countries [1]. Yet, total contribution by wind energy to production of world electricity energy at the beginning of 2006 has been very minuscule—0.7% of the total of 17,500 TW-hr [10]. It has its drawbacks by its v