The coordination between planners and operators of coupled energy systems will allow the further integration of renewable energy sources in the electricity network by storing energy in fuel form over long periods of time using power-to-gas, the recovery and more efficient use of heat, and the decarbonization of industrial processes and transportation modes that can’t be electrified. Energy networks, such as electricity grids and natural gas pipeline networks, have traditionally been planned and operated independently. In order to enhance the integration and coordination of different energy networks, they must be planned and operated in coupled ways. Different energy networks have historically been and are still modelled by different tools.