Two main challenges are facing the world in the 21st century. One is to meet the exponentially growing demand for energy, particularly in the developing countries, where today 1.6 billion people do not have access to commercial energy. The other is to deal with the global, regional and local environmental impacts resulting from the supply and use of energy. 

Renewable energy sources are considered to be clean energy sources but their large-scale use is hampered by the cost of generated energy and low utilization factor. Wind energy, however, has emerged as the most economical of renewable energy sources. There has been remarkable growth of wind power installations in the world. Germany is the world leader (installed capacity 8750 MW) in wind power, while India ranks fifth (installed capacity 1627 MW). Both countries have the common objective of supplying about 10% of their respective energy demand by using renewable energy by the year 2010. While the German program aims at reducing greenhouse gas emissions, the Indian program has the dual objective of providing energy to meet the growing demand and simultaneously controlling the emissions. In both the countries, the programs and nearly two decades old. It was, therefore, considered appropriate to have an appraisal of wind power technology and its environmental and social impact arising in both the countries. 

The contents of this book have been drawn from the deliberations of an Indo-German workshop jointly organized by Max Mueller Bhawan, The Associated Chambers of Commerce and Industry of India (ASSOCHAM) and the Indian Institute of Technology, Delhi. Participation from the industry, particularly Suzlon Energy Ltd. and Vestas RRB India Ltd. contributed significantly to the event. 

Though wind-generated electricity is already competitive with fossil based energy, the environmental and social aspects make wind power an attractive source of energy. The authors of various chapters have in a remarkable way provided a crisp insight of the wind power programs in India and Germany, and in discussing the environmental and social impacts. We hope that this work will continue the lively and informative exchanges that characterized the original workshop.