ABSTRACT
This chapter explores the concept of energy transition, focusing on the evolution of energy systems from their historical configurations to the sustainable models required for the future. An energy system comprises interconnected components and processes that produce, convert, store, distribute, and consume energy. Historically, these systems relied heavily on fossil fuels and centralized infrastructures, with limited integration of renewable energy sources (RESs) or advanced energy storage systems (ESSs).
The chapter reviews significant advancements over the past two decades, including the widespread adoption of wind and solar energy, the development of biofuels and synthetic carriers, and the increased use of ESSs like lithium-based batteries and hydrogen electrolysis. It highlights ongoing transformations in final energy use technologies, particularly the shift to electric urban mobility and energy-efficient residential systems.
These changes represent steps towards fully sustainable energy systems, which prioritize renewable energy, decentralized grids, and minimal environmental impact. The chapter introduces the concept of the energy transition as a structured path towards these goals, emphasizing the need for accelerated global action. The European Union’s ambition to achieve a fully decarbonized energy system by 2050 serves as a case study for the necessary technological, policy, and societal shifts.
The chapter concludes by setting the stage for an in-depth discussion of the key enabling technologies (KETs) required to complete the energy transition, covered in the subsequent chapters.
