Assessment of a hybrid stand-alone power system with hydrogen production and storage

In stand-alone power generation systems the intermittence of solar and wind energy sources requires the use of energy storage devices able to follow the time-varying electrical load demand. Energy storage based on hydrogen technologies is one of the most interesting options. The aim of this study is to investigate the performance of stand-alone power generation systems where the excess of electrical energy produced by wind turbines and photovoltaic modules is used in PEM hydrogen generators. Gaseous hydrogen is stored in pressurized vessels and used in PEM fuel cell stacks to produce electrical energy when required by final users. Excess of electrical energy can also be stored in a battery bank. In particular, this study was applied to the power generation and hydrogen storage facility being installed at the “Sardegna Ricerche Renewable Energy Cluster” near Cagliari in Sardinia. The expected performance of the stand-alone power generation system were evaluated through the commercial software HOMER, according to the available solar and wind resource data. Moreover, benefits coming from future implementations of the energy storage capacity were also assessed.