Energy Systems Transition: Digitalization, Decarbonization, Decentralization, and Democratization provides a thorough multidisciplinary overview of the operation of modern green energy systems and examines the role of 4D energy transition in global decarbonization mitigation efforts for meeting long-term climate goals. Contributions present practical aspects and approaches with evidence from applications to real-world energy systems, offering in-depth technical discussions, case studies, and examples to help readers understand the methods, current challenges, and future directions. A hands-on reference to energy distribution systems, it is suitable for researchers and industry practitioners from different branches of engineering, energy, data science, economics, and operation research.