A proposal for a vulnerability index for hydroelectricity generation in the face of potential climate change in Colombia

Abstract

The effect of potential climate change on the relationship water resources/hydropower generation in the Sinú-Caribbean Basin, Colombia, was analyzed. Climatic-hydrological variables that best express the vulnerability (positive or negative changes on water resources and related systems, and not precisely the definition of vulnerability given by the IPCC) of water resources in the region were identified, taking into account the current and projected values for the period of analysis 2010 to 2039. These variables were estimated based on the application of several general circulation models under greenhouse gas emissions scenarios A2. These scenarios were chosen considering that its outputs could provide a better basis to prevent adverse effects. The use of a weighted average scenario was proposed, and a vulnerability index for hydroelectric energy generation was established. In using the weighted average scenario was possible to determine the reduction of 13.3% in water storage volume in the reservoir with respect to the current scenario (year 2005 historic average), and the reduction of 22.8% in water storage volume with respect to the top of conservation storage capacity, and also, the reduction of 16.2% in energy generation with respect to current generation, and the reduction of 29.5% in energy generation with respect to the maximum hydropower generation capacity. The vulnerability index made it possible to determine (according to the models applied) that the hydropower generation system has a 44.4% low degree of vulnerability, a 22.2% medium degree of vulnerability, and a 33.3% high degree of vulnerability. In other words of nine analyzed models, four project a low degree of vulnerability, two medium degree and three a high degree of vulnerability.