Sustainable Energy for Islands: Opportunities versus Constraints of a 100%Renewable Electricity Systems. El Hierro (Canary Islands) and Flores (Azores) case studies

Abstract: Islands? characteristics provide several advantages as laboratory for studying 100% renewable energy sources (RES) systems. Their isolation makes them a ?unique laboratories, to gain knowledge and understanding of people/environment relationships? ; to prove its feasibility and acquire the needed knowledge for such systems to work; to be pioneer project, basis of other islands? projects and even a global 100%RES electricity system. The objective of this research has been to evaluate if 100% renewable electricity systems are feasible based on the experience being done in two European islands? with different RES potentials and 100% RES commitment. For such a system to be sustainable, a proper renewable energy potential to cover the actual and future demand is needed. A holistic approach is required; a case specific combination of RES has to be established. Profitability in the exploitation of renewable energy sources has to be assured. The electricity market has to lead to the convenient energy mix, as to support the subsistence of the electricity system. A proper governmental intervention will be required. The, traditionally not accounted, social and environmental cost of the electricity systems can play a significant role in its feasibility. Factors influencing the sustainability of the system; driving forces, risk and barriers has been identified.