Vulnerability of hydropower project under changing climate

Decision makers are concerned with the likely impacts of climate change on the hydropower business. Hydropower generation is proportional to the available water at any given time. Since the hydrologic regime of a stream is function of various climatic variables, the changing climate is posing a threat to the water availability and its seasonal distribution. This is likely to affect the hydropower generation and the associated revenue. Additional stress to the hydropower business can occur from fluctuating electricity prices and the unfavorable gap between the supply and the demand. In order to access the vulnerability of the project it is imperative to test the system for the various stresses. In the present research stress-testing of a hydropower facility located in northern Ontario is carried out. The future streamflows are assessed by employing the hydrological model, Soil and Water Assessment Tool (SWAT). To ascertain the robustness of the model simulation, multi-objective calibration strategy has been adopted. The calibrated model is then forced with the climate data from an ensemble of six regional climate models (RCMs) which simulates the stress due to changing climate. Annual average change in generation is not significant but an increase of 31% during spring and reduction by 41% during summer are concerning. A feasible range of market electricity price and a range of percentage gap between demand and supply are modeled as additional stresses in the system. A range of total annual revenue generated is thus computed to access the vulnerability of the system.