Calculation of adequacy indices for interconnected Spanish electric systems in presence of RES, hydro and pump units

This article presents the recent developments in the methodology for the calculation of LOLE and EDNS in the Spanish electrical systems; these solutions can be directly applied or easily adapted to fit any other system as well. Starting from an existing probabilistic methodology, a new tool was created to address not only thermal power units but to include new features such as renewable generation technologies, higher degree of interconnections, and pumped hydro storage. Several areas of improvement have been identified and addressed. A recursive algorithm to treat the mutual support among interconnected systems is developed; stochastic contribution of wind power and other RES is added or improved; pump storage hydro units are considered, thanks to an optimization of the hydro resources; conventional hydro is modelled based on the historical availability of primary resource.