In this section, we describe the development of a complex multi-domain electromechanical system as an interconnection of simpler subsystems. We first give a global overview of the total system to be modelled, then describe the subsystems of the model, and conclude with final remarks on how network modelling was used in this problem, and to what benefit. Our electromechanical system exchanges energy between the power grid, a local mechanical source and a local general load, which may contain subsystems from any domain.