This book presents the select proceedings of the first International Conference on Energy and Materials Technologies (ICEMT) 2021, organized by the Department of Mechanical Engineering, Sri Sivasubramaniya Nadar College of Engineering, Kalavakkam, India. It covers the recent technologies in two broad thematic areas: energy and materials. Various topics covered in this book include hybrid energy, advanced energy systems, energy management, energy policy, geothermal, nuclear energy, bio-energy, waste to energy, power plants, and automotives. The book will be useful for students, researchers, and professionals in the area of mechanical engineering, especially various domains of energy.