Models on the wrong track: Model-based electricity supply scenarios in Switzerland are not aligned with the perspectives of energy experts and the public

Model-based scenarios have become the key method to explore uncertainties in the electricity supply transition of many countries. While retrospective scenario studies show that multi-organization, multi-model scenario ensembles increase the diversity of considered uncertainties, it remains unclear whether such ensembles align with the perspectives of transition stakeholders, including the wider public. This study compares a multi-organization, multi-model ensemble of 82 Swiss electricity supply scenarios for 2035 from a review of 19 studies between 2011 and 2018 with preferred scenarios from three samples of stakeholders: citizens from an online survey (N=61), informed citizens from participatory workshops (N=46), and energy experts from another online survey (N=60). The results show that most informed citizens and experts preferred an almost 100% domestic renewable electricity supply in Switzerland in 2035. On the contrary, most model-based scenarios relied significantly on fossil fuel-based generation and net electricity imports. Possible reasons for this misalignment include the lack of broad stakeholder participation in the development of such scenarios and the modeling choices such as cost-optimization models that are known to underrepresent renewable electricity. For both scenario developers and users, this study offers a word of caution that even a rich scenario ensemble could focus on alternatives that are not preferred by stakeholders and that diverse stakeholder and public perspectives can enrich scenario ensembles. For the Swiss electricity supply transition, the results indicate that a large-scale deployment of renewable electricity before 2035 is preferred by the expert and citizen samples and, therefore, such scenarios should be modeled more in the future.