Sizing and analysis of big scale and isolated electric systems based on renewable sources with energy storage

A considerable number of institutions, companies and societies demand and trust the possibility of a sustainable world where the energetic production is based on renewable sources. Most likely future problem of the no-controllable renewable electric production (mainly wind and solar) may be the temporally variability. To follow the power demand is necessary controllable generation. The paper analyses based on hypothetical situations how to manage through storage systems the no-controllable productions to get the complete substitution of the no-renewable power plants. Data from real renewable plants has been used to explore in big electric systems (Spain) the optimal sizing of said storage systems. It is shown that with a potential renewable overproduction around 150% versus a yearly demand only a 1.5% energy storage capacity versus demand should be necessary.