Renewable energy scenarios in the portuguese electricity system

Portugal has been demonstrating over the years a high dependence of imported fossil fuels, especially with regard to the transportation and electricity production sectors. The urgent need to balance supply and demand as well as the growing concern about environmental issues and reduction of external energy dependency justified an increasing interest in the exploitation of renewable energy sources (RES) looking for more efficient strategies in terms of economic and social or environmental dimensions. The electricity sector represented a clear example of this RES trend with European and Portuguese policies focused on strategies promoting renewable resources and energy efficiency. Following different studies already conducted in other countries, this paper presents an approach to a possible 100 % renewable electricity scenario in Portugal, supported by the application of the model EnergyPLAN. The importance of the interconnection as stabilization measure for a system highly dependent on renewable energy sources of variable output is put in evidence. The results also established that the cost structure of each scenario is mainly driven by the low marginal cost of renewable technologies along with their high investment costs