Dynamics of long-term electricity demand profile: Insights from the analysis of Swiss energy systems

Electrification becomes the most cost effective option to decarbonise the energy system by integrating large share of intermittent renewable energy sources. Numerous analytical tools/methods have been developed for analysing long-term electricity supply by incorporating advanced features. In almost all analyses, historical load profile has been assumed for the future electricity demands, i.e., load profile is linearly extrapolated or interpolated with respect to the change in annual electricity demands. This approach undermines the implication of emerging electrification such as e-mobility. New methods have been explored to generate future load curves. A limitation of such methods is that they ignore the interdependency between electricity supply and demands. Energy system approaches have advantages of determining the electricity demands endogenously and often have limited temporal representation to deal with infra-annual variability. This limitation has been widely addressed by introducing higher level of intra-annual time slices. Using a set of exemplary Swiss energy scenarios from the Swiss TIMES energy systems model with an hourly time resolution, this paper aims to showcase 'how can the electricity load profile evolve under different boundary conditions' and 'how can electricity supply influence the choice of end use technology'. The scenario analyses show that for changes in the annual electricity demands of - 3% to + 38% in 2050 relative to 2010 levels, the corresponding changes in winter peak are between - 30% and + 30% whereas summer peak consistently increase by 2%-23%. Summer peak is more pronounced due to growing air-conditioning demands whereas winter peak depends on emerging electrification requirements for heating and mobility.