Nexus-e is the central tool for the SWEET consortium to provide scenarios, outlining which pathways are feasible and which ones are potentially problematic, considering technical, economic, and social constraints for the national scale and regional scale. We assess these pathways with respect to efficiency, flexibility, resilience, cost-competitiveness, and sustainability. For this task, Nexus-e is further extended to represent the full energy system in Switzerland. This extension, in particular, focuses on industry and heating, transportation and the gas network, and allows us to conduct the following three assessments.

First, we assess the techno-economic potential of sector-coupling for the industry and heating sector. We consider all industry sectors in terms of energy consumed and supplied, revealing synergies through, e.g., waste heat available for the domestic heating sector. A particular focus will lie on the chemical industry, given its potential for both sector-coupling and flexibility due to its high energy use, waste heat potential, and need for chemical feedstocks that could also serve as energy carriers and/or storage. We consider residential and industrial heating demands and future trends on their corresponding temperature levels as well as a wide range of technology options and heat sources to determine the optimal pathway to decarbonize the heating sector.

Second, we assess the techno-economic potential of transportation in Switzerland for providing flexibility through electrification and sector-coupling. To do so, we represent the evolving demand of electricity, synthetic fuels, and other energy carriers used in transportation in Nexus-e. We consider the possible electrification of transportation (e.g., cars, ferries, trucks) and the pathways for decarbonizing the hard-to-electrify modes of transportation (e.g., shipping, aviation), for example, through sector coupling. We also perform a detailed assessment of the increased flexibility potential and how it benefits the Swiss energy system.

Third, we assess the role of the Swiss gas network in flexibility provision. We consider the use of synthetic gas located in key industrial sites and power-to-gas sites and of gas storage facilities as long- and short-term flexibility providers in connection with their operations within the gas grid. Furthermore, we will investigate whether the deployment of flexibility providers using synthetic gas needs a gas network infrastructure or rather point-to-point pipeline connections linking relevant gas synthesis and consumption sites.