Planning for a 100% renewable energy system for the Santiago Island, Cape Verde

Abstract

Ensuring the supply of affordable energy, improving energy efficiency and reducing greenhouse gas emissions are some of the priorities of the governments of several countries. The pursuit of these energy goals has triggered interest in the exploration and usage of Renewable Energy Sources (RES), which can be particularly appropriate for island systems as is the case of Cape Verde. This work proposes a generation expansion planning model for Cape Verde considering a 20 years’ period. Different scenarios were analysed, each one representing a possible RES contribution for electricity production, reaching a 100% RES share. The results demonstrate that the increase of the RES in the system will lead to an increase in the total system cost. However, a significant decrease in both CO2 emissions and external energy dependency of the country is projected. The seasonality of the RES resources, and in particular of wind power is shown to be one of the most important challenges for the effective uptake of such a renewable power system. A least-cost solution might be possibly achieved if storage technologies would be considered within the modelling approach (e.g. battery and Power-to-Gas technologies) which would also contribute to accommodate the Critical Excess of Electricity Production (CEEP). While the proposed model allowed already to present some useful scenarios, it becomes also evident the need to expand the analysis by using hourly data and taking into account the sector’s integration (e.g. power, heat and transport).