Solar photovoltaic potential to complement hydropower in Ecuador : a GIS-based framework of analysis

Sammanfattning: In Ecuador, more than 85% of electricity production relies on hydropower and consequently the supply of electricity relies on water availability. During the dry season (October-March) hydropower capacity could diminish up to one-third of its installed capacity or more under a severe drought causing a substantial augmentation of thermoelectric power output to offset the lack of hydropower to cover electricity demand, and consequently increasing the overall operational cost and emission of CO2 of the power system. Compensating hydropower seasonality with non-hydro renewable energy is thus necessary to safeguard and maintain in the long-term the supply of clean and affordable electric service. This thesis studies the potential of non-hydro renewable energy such as PV to compensate the seasonality of hydropower and assess its impact on the long-term expansion of the Ecuadorian power system. To do so, a GIS-based and participatory multi-criteria analysis is applied to find the best suitable areas to deploy PV power that is complementary to hydropower from a technical, economic and environmental viewpoint. Then, using the Stochastic Dual Dynamic Programming software a long-term simulation (2019-2030) of the power system’s operation under a baseline and alternative expansion scenario without and with PV respectively is performed in order to assess the economic and environmental impact of integrating complementary PV in the expansion of the Ecuadorian power system. Results indicate that the installation capacity potential of complementary PV is 35,7 GWp which is equivalent to 4.3 times the actual capacity of the Ecuadorian power system, and it is distributed in suitable land areas mainly in the South of Ecuador with a total area of 805 km2 that is equivalent to 0.3% of the area of the country. Comparing simulation results of power system expansion scenarios shows that the alternative scenario that considers a high penetration of PV in the power system (3.9 GWp) reduce by half the annual operational cost of the power system and more than one quarter (33%) of the lifecycle GHG emission by 2030. Thus, integrating PV rather than thermoelectric power in the long-term expansion of the power system is the best option from an economic and environmental viewpoint. This study set the basis to encourage planners and decision makers to consider these findings for future expansion plans in order to set up a sustainable power system for Ecuador at low cost and environmental impact.