Conversion of electrons bound in molecular orbitals into mobile electrons and back in a controlled and efficient way is key for a sustainable energy supply. For instance, the efficient generation and control of mobility of free charge carriers are key features for the direct conversion of solar into electric energy. Incorporation of mobile electrons into new molecular orbitals is in turn an essential step for the storage of this energy in renewable fuels. As in many other application areas computational modeling and simulation has evolved into a major contributor to a rational development of corresponding concepts. Employed are efficient computational screening strategies for the identification of novel materials, just as much as detailed, often multi-scale type approaches that generate mechanistic insight into the relation between elementary steps and macroscopic functionality. In the talk I will review some of our recent contributions to this highly interdisciplinary field, focusing in particular on a virtual screening for high carrier-mobility organic materials and electrocatalysis beyond the computational hydrogen electrode.