Green energy is derived from natural processes that produce small amount of pollution. Some of the resources used for this purpose are wind power, solar power, geothermal power, hydro power etc. Environmental systems include all the factors that affect the development, survival and evolution. This book unravels the recent studies in the field of green energy and environmental systems. It will also provide innovative topics for research which interested readers can take up. Scientists and students actively engaged in this field will find this book full of crucial and unexplored concepts. It extensively discusses the emerging technologies that increase energy efficiency. This text will serve as a valuable source of reference for engineers, environmentalists, ecologists, conservationists, professionals and students associated with this area.