The energy derived from renewable sources such as sun, wind, rain, tides, etc. is known as renewable energy. These sources are preferred over conventional sources of petroleum and coal because they are naturally replenished in small timescales. They can be found in almost every geographical area unlike conventional resources. Some of the most widely used renewable energy technologies include wind power, hydropower, geothermal energy and solar power. They are primarily used for the purpose of electricity generation, apart from usage in the transportation industry. This book is a compilation of chapters, which discuss the most vital concepts and emerging trends in this field. It includes some of the most significant pieces of work being conducted across the world, on various topics related to renewable energy. Researchers and students actively engaged in this field will be assisted by this book.