Abstract
Interactions between different energy carriers (electricity, heat and gas) are considered beneficial for using renewable energy and reducing carbon emissions in the energy system. Nevertheless, the establishment of such hybrid grids or systems, also called multi-, integrated or smart energy systems, remains relatively unexplored. The concept is characterised by great complexity, questioning the common isolated view of energy grids. This paper analyses the changing requirements from historically grown, isolated energy grids towards renewable hybrid energy systems and the associated potential and challenges. A hybrid grid offers alternative use options, which make energy production and consumption more flexible. No peer-reviewed research provides quantitative analysis on the expected utilisation of the electricity, gas and thermal grid in a hybrid grids scenario. However, the traditional grids will compete among each other and increasingly with distributed power generation and consumption by prosumers. In addition, a reversal and reduction of the gas grid and possible new structures of a hydrogen network have to be considered. To achieve the desired savings in energy demand and carbon emissions while maintaining the security of supply and economic feasibility in hybrid energy systems, appropriate technologies, infrastructure financing, integrated system planning based on the relevant data and supportive market frameworks are required.