This book presents a new approach to analyzing energy system issues. By first exploring basic concepts, energy history from the discovery of fire to post-industrial societies and the transition from bio-fossil, energy sources and types, energy potentials around the world, as well as methods for analyzing and analyzing economic projects The field of energy in the first chapters or chapters of the concepts attempts to provide the reader with the ability to analyze and explore the energy world. This book then examines trends in the portfolio of energy portfolio changes to future chapters in internationally acclaimed research that, like many other topics, the energy market will be changing. Although the human need for energy is unimaginable, their forms of energy and their share of the energy portfolio are changing. the ultimate aim of this book is to train experts in the energy system analysis and modeling of the energy systems.