Diverse efforts in the same direction: A multi-model comparison of climate-neutrality power sector pathways for the Nordic countries

The Nordic countries have adopted ambitious climate targets that imply far-reaching transformations of their power sectors, making energy system modelling and scenario analysis a central input to long-term policy analysis. At the same time, comparisons across modelling studies are complicated by differences in model structure, assumptions, and data. This paper presents a comparative assessment of Nordic power sector transition pathways generated by eight structurally diverse energy system models, analysed without harmonising inputs in order to reflect prevailing modelling practice. The analysis examines where model outcomes converge or diverge and identifies the main drivers of these differences. Key indicators include generation capacity across major technologies, power-sector CO2 emissions, and the deployment of carbon capture and storage (CCS). Across models, there is broad agreement on a transition dominated by variable renewable energy in which wind power, complemented by solar photovoltaics, forms the backbone of the power system by 2050, alongside a declining role for nuclear power. At the same time, projected capacity levels, CCS deployment, and emissions outcomes vary substantially, reflecting differences in renewable resource assumptions, technology scope, system boundaries, and other structural modelling choices. Net-zero outcomes range from small residual emissions to net-negative values by mid-century, underscoring the importance of transparent scenario design and cautious interpretation of multi-model scenario analyses used in planning and policy contexts.