For being densely populated and urbanized, and for concentrating high-value economic activities, estuarine regions have an increased energy demand, which boosts the claim for new, efficient, renewable, and safe energy production. Among these technologies, hydrokinetic energy conversion systems are potentially well-suited for estuaries. However, in the actual context of climate change, it is important to know how changes in mean sea level may affect hydrokinetic energy production. This work proposes a methodology to assess the hydrokinetic energy potential for future scenarios using numerical hydrodynamic modeling techniques. Applied to the Douro estuary, several scenarios considering present conditions, as well as medium (2050) and long-term (2100) predictions under different Shared Socioeconomic Pathways are proposed. The results revealed that the studied region maintains a high dependence on freshwater discharge until 2100, although tidal oscillation is also significantly perceived in the entire estuary. Overall, hydrokinetic power potential will not increase with the mean sea level rise and will instead be considerably lower. Therefore, a decline in the kinetic energy available for exploitation is expected with increasing CO2 emissions, along with the associated intensification of sea level rise. Results reinforce the need to perform local studies to evaluate future trends in hydrokinetic energy production.

This research was supported by the Strategic Funding UIDB/04423/2020 and UIDP/04423/2020 through national funds provided by FCT – Foundation for Science and Technology and European Regional Development Fund (ERDF), and by the project EsCo-Ensembles (PTDC/ECI-EGC/30877/2017), co-financed by NORTE 2020, Portugal 2020, and the European Union through the ERDF, and by FCT through national funds. The authors would like to thank the Instituto Hidrográfico, EDP Energias de Portugal and the projects ECOIS (POCTI/CTA/48461/2002), RAIA (0313-RAIA-1-E), RAIA. co (0520-RAIA CO-1-E), RAIA tec (0688-RAIA TEC-1-P), ECORISK (NORTE 07 0124-FEDER-000054) and INNOVMAR/ECOSERVICES (NORTE 01 0145-FEDER-000035) for the data provided.