This book discusses the fundamental as well as modern approaches and technologies related to the fields of renewable energy and biofuels. Renewable energy sources can be replenished in a given time frame and have the potential of replacing pollution causing fuels such as fossil fuels. Biofuels are derived from plants and other resources such as commercial, agricultural and domestic waste through biological processing using bacteria for anaerobic digestion. Biofuels are a commonly known form of renewable energy. The need to reduce the hazardous effect of non-renewable forms of energy has led to rapid progress and extensive research in this area. This extensive book collates researches from across the globe which explore the diverse aspects of renewable energy and biofuels. Different approaches, evaluations, methodologies and advanced studies have been included in this book. It will benefit researchers and students alike.