This white paper presents the reference architecture of the SEGRID project’s use case 2 scenario 2: central load balancing of renewable energy. The reference model is described with its different ICT components and configurations. As supplementary material to this report, four models devised in the securiCAD threat modelling tool are provided. The four models represent four different alternative configurations of the reference architecture. The models are intended as a starting point and support for further cyber security analyses of other smart grid scenarios.