Can we optimise for justice? Reviewing the inclusion of energy justice in energy system optimisation models

Energy systems optimisation models are used for analysing energy systems and questions of e.g. greenhouse gas mitigation aligned with the Paris Agreement. However, the techno-economic nature of energy system models has opened for discussions about how well societal aspects are represented. Studying justice implications in energy systems modelling is an opportunity to inform policy-makers and the broader society how long-term changes to energy systems may affect different social groups and how to minimise injustices. In this paper, we review how, and to what extent, aspects of social justice have been included in energy systems optimisation modelling as well as areas for future research. In addition to reviewing published journal articles and reports, we organise a workshop with energy system modellers and social scientists, providing qualitative information on past approaches and potential future venues. We identify 3 key findings: (i) Exploring alternative system configurations to cost-optimality is receiving increasing attention and typically done through a ‘modelling to generate alternatives’ approach, (ii) among formalised definitions of distributional justice, equality (equal distribution) is the most common equity principle. There is at the same time little reflection on the choice and impact of equity principles, potentially contributing to an overly narrow understanding of justice. (iii) Among the workshop participants, participatory approaches which involves stakeholders and lay people are considered a potential future area of research, especially for making modelling results and processes more accessible and impactful to the wider public.