The triple “generation, conversion and storage of energy” are the fundamental building blocks toward realizing the general aim of an energy supply on demand as unrestricted as possible. Meanwhile, however, it has become clear that this general aim leads to conflicting feedback loops on the ecological environment. Growing awareness of such deteriorating feedbacks has triggered worldwide activities to search for technical approaches in order to at least reduce the negative environmental consequences of energy consumption. At this point, materials science plays a central role. The contributions to this Thematic Series cover a plethora of research fields from materials-related problems that concern fuel cells, Li-based batteries, and organic solar cells, to energy-related applications of nanographite and silicon nanotubes as well as the optimization of thermoelectric materials and electrochemistry-based microscopy.