During his PhD studies, Ricardo Fernandes investigated how CO₂ can be managed in a climate-neutral European energy system, focusing on the roles of CO₂ capture, transport, conversion (utilisation), and sequestration, as well as carbon dioxide removal (CDR) strategies. Through the modelling of this energy system, his research shows that nationally defined emissions limits provide a more realistic representation of the EU’s distributed governance structure, increasing total system costs by only 1.4% compared to a single EU-wide limit. Several CDR strategies–afforestation, perennialisation, and enhanced rock weathering–play a significant role in achieving a cost-efficient climate-neutral system, reducing total system costs by about 9% and enabling the removal of 169 MtCO₂ annually. Direct air capture is not required when these CDR strategies are combined with a continent-wide CO₂ transport network. Overall, Ricardo’s work advances energy system modelling and provides policy-relevant insights for designing cost-effective strategies to achieve climate neutrality in Europe by 2050.

The PhD study was completed at Department of Mechanical and Production Engineering, Faculty of Technical Sciences, Aarhus University.

This summary was prepared by the PhD student.

Time: Friday, 17 April 2026 at 13:00
Place: Building 5125, room 408, Lecture Theatre Edison, Department of Electrical and Computer Engineering, Aarhus University, Finlandsgade 22, 8200 Aarhus, Denmark
Title of PhD thesis: Carbon capture, transport, conversion, and sequestration in a highly renewable European energy system
Contact information: Ricardo Fernandes, e-mail:ricardo.fernandes@mpe.au.dk
Members of the assessment committee:
Professor Falko Ueckerdt, Interdisciplinary Transformation University Austria, Austria
Senior Researcher Markus Millinger, Research Institute of Sweden (RISE), Sweden
Associate Professor Ulrich Doll (Chair), Department of Mechanical and Production Engineering, Aarhus University, Denmark
Main supervisor: Associate Professor Marta Victoria, Department of Mechanical and Production Engineering, Aarhus University, Denmark
Co-supervisor: Professor Martin Greiner, Department of Mechanical and Production Engineering, Aarhus University, Denmark
Language: The PhD dissertation will be defended in English

The defence is public.
The PhD thesis is available for reading at the Graduate School of Technical Sciences/GSTS, Ny Munkegade 120, building 1521, 8000 Aarhus C.