This book explores the critical role of energy management in addressing global challenges such as climate change, economic sustainability, and environmental conservation. As energy remains a pivotal force in all industries worldwide, managing energy efficiency has become paramount. The book delves into various aspects of energy management, emphasizing its synergy with energy technology and innovation culture. Essential coverage includes: The relationship between energy rationality and environmental sustainability; Advanced methodologies such as exergy and entropy-based approaches to optimize energy utilization and minimize waste; The importance of sector-specific decarbonization strategies in achieving sustainability goals. Energy Rationality and Management for Decarbonization serves as a comprehensive guide for policymakers, corporate leaders, and researchers interested in harnessing the power of efficient energy management to drive sustainable development and address pressing global challenges.