The book collects the latest research and thinking from international experts on green computing and the smart city. The financial and environmental costs of energy are a concern in smart cities due to the high usage of computing, technology, security, IoT, communications, traffic, and other technologies. This book tackles this problem with a focus on computing, reporting on various approaches being taken worldwide, illustrated by several international case studies demonstrating these approaches. Researchers use this book as an up-to-date reference and engineers use it as a guide for the design and implementation of real solutions.