This paper shows a study for the optimization of a PV-Wind-Diesel system with hydrogen storage located near Zaragoza (Saragossa) in Aragon, Spain. The study optimizes a renewable energy system with AC diesel generator and hydrogen storage with electrolyzer, hydrogen tank and fuel cell, to supply electric power to the loads.

As design tool the HOGA sfotware has been selected, where the acronym stands for Hybrid Optimizations by Genetic Algorithms. HOGA software uses genetic algorithms to find the optimal design of a hybrid system in much lower CPU time compared to other enumerative algorithms. This software, developed at the University of Zaragoza with the collaboration of the Foundation for Hydrogen in Aragón, has been taken as reference tool of IEA HIA (Hydrogen Implementing Agreement) Subtask 18b “Integrated System Evaluations”. The software is freely downloadable at the website of the Foundation for Hydrogen in Aragón (http://task18b.hidrogenoaragon.org/)

The objective function to minimize in the design process is the total Net Present Cost (NPC) of the system. The system is defined as a combination of components (PV generator, wind turbine, diesel generator, electrolyzer, hydrogen tank and fuel cell) and control variables. In this paper several load profiles have been applied, comparing the results and showing the importance of the Demand Side Management.