Climate change impacts on reservoir inflows and subsequent hydroelectric power generation for cascaded hydropower plants

This study describes a procedure for investigating climate change impacts on reservoir inflows and subsequent hydroelectric power generation (HPG) for cascaded hydropower plants. By integrating a weather generator, an HBV-based hydrological model and an HPG simulation model, both the reservoir inflows and subsequent HPG amounts during the baseline period (1980-1999) and the future period (2020-2039) were simulated and compared. The downscaled rainfalls and temperatures under the A1B and B1 emissions scenarios from seven general circulation models (GCMs) were used to generate the reservoir inflows. The simulated seasonal inflows, averaged by the multi-model ensemble approach for the seven GCMs, tend to decrease in the future. Under the A1B scenario, the percentage change in HPG for the seven GCMs ranges between -14.9% and 4.6% during the May-October wet season and between -33.1% and 0.2% during the November-April dry season. Under the B1 scenario, the corresponding values are -19.6% to 4.1% and -30.6% to -6.4% during the wet and dry seasons, respectively.