Comparing future patterns of energy system change in 2 °C scenarios to expert projections
Mariësse A.E. van Sluisveld (Copernicus Institute of Sustainable Development – Utrecht University, PBL Netherlands Environmental Assessment Agency); Mathijs J.H.M. Harmsen (Copernicus Institute of Sustainable Development – Utrecht University, PBL Netherlands Environmental Assessment Agency); Detlef P. van Vuuren (Copernicus Institute of Sustainable Development – Utrecht University, PBL Netherlands Environmental Assessment Agency); Valentina Bosetti (Economic Department – Bocconi University, Fondazione Eni Enrico Mattei); Charlie Wilson (Tyndall Centre for Climate Change Research – University of East Anglia); Bob van der Zwaan (Policy Studies, Energy research Centre of the Netherlands ECN, Faculty of Science HIMS – University of Amsterdam, Faculty of Science HIMS – University of Amsterdam)
Global Environmental Change, Volume 50, 2018, Pages 201-211
Integrated assessment models (IAMs) are computer-based instruments used to assess the implications of human activity on the human and earth system. They are simultaneously also used to explore possible response strategies to climate change. As IAMs operate simplified representations of real-world processes within their model structures, they have been frequently criticised to insufficiently represent the opportunities and challenges in future energy systems over time. To test whether projections by IAMs diverge in systematic ways from projections made by technology experts we elicited expert opinion on prospective change for two indicators and compared these with the outcomes of IAM studies. We specifically focused on five (energy) technology families (solar, wind, biomass, nuclear, and carbon capture and storage or CCS) and compared the considered implications of the presence or absence of climate policy on the growth and diffusion of these technologies over the short (2030) to medium (2050) term. IAMs and experts were found to be in relatively high agreement on system change in a business-as-usual scenario, albeit with significant differences in the estimated magnitude of technology deployment over time. Under stringent climate policy assumptions, such as the internationally agreed upon objective to limit global mean temperature increase to no more than 2 °C, we found that the differences in estimated magnitudes became smaller for some technologies and larger for others. Compared to experts, IAM simulations projected a greater reliance on nuclear power and CCS to meet a 2 °C climate target. In contrast, experts projected a stronger growth in renewable energy technologies, particularly solar power. We close by discussing several factors that are considered influential to the alignment of the IAM and expert perspectives in this study.