Author(s): Babar Mujtaba; Paulo Diogo; Pedro Beca; Sofia Simoes; Patricia Fortes; Filipa Amorim

Linked Author(s): Paulo Diogo, Pedro Beça

Keywords: Long-term climate projections; Hydrological modelling; Hydropower production; Climate change scenarios

Abstract: Climate conditions have a significant impact on energy demand and production. The project CLIM2POWER, completed in 2021, aimed to develop a climate service at European scale for the planning of the power infrastructures operations using seasonal forecasts and long-term climate projections. This work presents part of the project, and focus on assessing the climate change impacts on hydropower production of Torrão Dam. Torrão reservoir is located on the Tâmega river, a tributary of the Douro river in northern Portugal. The long-term (2016-2100) climate data used is obtained from the EURO-CORDEX simulations, on a daily time scale. Two different combinations of regional and global climate models for scenarios RCP 4.5 and 8.5 (four combinations) were used: ICHEC-EC-EARTH-CLMcom-CCLM4 (CCLM4) and ICHEC-EC-EARTH-DMI-HIRHAM5 (HIRMAM5). Long-term precipitation data was bias-corrected using the multiplicative shift method, and for rainfall-runoff simulation, HEC-HMS model was used. The results showed that 30-years total annual precipitation for future periods (i.e, 2016-2040, 2041-2070 and 2071-2100) was 3.4%-28.1% lower than the historical one. 30-years annual total discharges of all future periods decreased for both models and RCPs (1.2%-30.2% less than the historical ones). Regarding future 30-year annual average capacity factors, there was reduction (1.8%-24.8%) with respect to historical one, except in two future periods for CCLM4 model of RCP 4.5 scenario i.e., 1.2% increased in the period 2016-2040 and 1.5% increased in the period 1971-2100. This suggest that hydropower production is not only dependent on future precipitation trends but also on the hydropower production procedures.

DOI: https://doi.org/10.3850/IAHR-39WC2521711920221138

Year: 2022