The engineering design and R&D of auxiliary heating systems and their sub-systems are a key activities in the frame of the present conceptual design phase for a first of a kind DEMOnstration Fusion Power Plant in order to develop a system capable of achieving and controlling burning plasmas. In the frame of the EU DEMO reference design, the R&D activities consider the injection of about 50 MW of Electron Cyclotron (EC) power to support and assist different plasma phases. As the project is still in the conceptual phase, a range of options for gyrotrons, transmission lines and antennas is under assessment taking into account the guidelines for the integration of the EC system in a nuclear reactor and a maximal achievable reliability and availability of the EC power during operation.