Energy for Sustainable Society

9Wind Energy Systems

View of the first offshore wind farm in the United States from South of Block Island, RI. The 30‐MW, five‐turbine Block Island Wind Farm began commercial operations in December 2016. The project was developed by Deepwater Wind. (For more information visit: http://dwwind.com/project/block-island-wind-farm/ Accessed on 10/22/2019).

9.1 Introduction

Wind is a clean, sustainable, and renewable source of energy. Wind power has been an essential driving force of the economic development since early civilizations. For thousands of years, sailboats carried voyagers and merchandise on rivers, lakes, seas, and oceans. Windmills powered water pumps, grain‐grinding mills, and various mechanical equipment throughout the centuries; Antique communities used windmills to pump water. In the eleventh century, grain‐grinding vertical‐axis windmills supported the agriculture in Persia and the Middle East. In the medieval age, crusaders and merchants traveling to Asian countries brought the idea of converting wind energy into rotational mechanical work to Europe. More advanced mechanisms using gear trains allowed development of horizontal axis windmills. By the thirteenth century, Dutch engineers used windmills to pump water out of areas below sea level. The windmills used to drain wetlands transformed swamps and marshlands into fields suitable for agriculture and other development. ...