Researchers from EPFL and HES-SO Valais have conducted a study modeling the Swiss energy system with the hypothetical constraints of carbon neutrality and energy independence by 2050. The results indicate that these goals could be achieved while reducing energy system costs by approximately 30% compared to 2020.
The study demonstrates that Switzerland has the potential to achieve a carbon-neutral and independent energy system by 2050 by tapping into its untapped local renewable energy resources. Remarkably, this system could even be more cost-effective than the country’s energy system in 2020, assuming the same constraints, with potential cost reductions ranging from 30% to 32%. These findings could pave the way for a stronger commitment to domestic investment in clean energy.
Although complete energy independence is not a specific goal, aligning with the Federal Act on Climate Protection Objectives (scheduled for a Swiss vote in June 2023), carbon neutrality by 2050 is a crucial target. The researchers employed their modeling framework, EnergyScope, to simulate a fully energy-independent Swiss state to ensure theoretical supply security and subsequently evaluate the impacts of imports and exports. The model generated cost-optimal investment options to meet the demands of Swiss society, including households, transportation, and industry, while considering existing or reinforced infrastructure.
The EPFL research team, led by François Maréchal from the Industrial Process and Energy Systems Engineering group (IPESE), concluded that achieving the aforementioned goals would require a significant increase in photovoltaic (PV) and wind electricity generation. To reach an economic optimum, it is suggested that approximately 60% of Switzerland’s roof area be covered with PV systems.
Jonas Schnidrig, a Ph.D. student from EPFL and HES-SO Valais and the first author of the study published in Frontiers in Energy Research, highlights the unexploited solar PV potential in already-built-up areas of Switzerland. He suggests that an economic optimum can be achieved by covering fewer than two out of every three roofs, emphasizing the need to determine the most suitable roofs for PV installations.
As solar production is more prominent in the summer, while wind intensity increases in winter, striking the right balance between electricity generation and seasonal storage becomes crucial to meet Switzerland’s energy demand throughout the year, particularly in the winter season. The study proposes that the predominantly summer-oriented solar production could be optimally complemented by deploying wind capacity, which primarily generates electricity in winter, alongside hydroelectricity and biomass.
The researchers also demonstrate that there are multiple equivalent solutions and assess their sensitivity to cost uncertainties. The models highlight the interdependence of different options and the influence of technological choices on other investments and infrastructure.
In conclusion, the researchers assert that the key difference lies in the nature of costs. The current Swiss energy system heavily relies on (inexpensive) imports rather than domestic investment. Consequently, consumers bear the cost and depend on resources and technologies that are sourced and operated outside Switzerland. On the other hand, the future system modeled in this study is based on local investment and the utilization of indigenous resources, which appears to be the most economical and resilient choice in the long run, according to François Maréchal.