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The objective of this work is to discuss design considerations related to the development of a stand-alone photovoltaic driven hydrogen production and consumption system. The referred system is currently on the design-phase so this work describes in particular the associated design considerations, governing equations, schematics and the expected system efficiency. The system design requirements include the production of enough energy to power an average residence located in the Ica city, Peru. The system design has been divided in four subsystems, each one having its own design considerations and limitations, (i) power, hydrogen (ii) production, (iii) storage and (iv) consumption. Regarding the power subsystem, the required considerations to generate the maximum amount of solar energy in the minimum amount of space are presented. For hydrogen production, different electrolyzer related technologies have been accounted for; including proton exchange (PEM), alkaline (AEC) and polymer (PEC). Hydrogen and oxygen storages are a critical aspect in the full hydrogen chain production. Currently no single technology satisfies all of the criteria required. As such, present technologies and selection considerations are presented. For using the produced hydrogen, fuel cell stacks including PEM and solid oxide ones are assessed. Finally, the right the combination of current, voltage (including conversion from DC to a constant AC supply) and fuel utilization maximizing efficiency and power output is determined.

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Hydrogen production through electrolysis is an important research topic since the use of hydrogen as a fuel has the potential to significantly reduce gaseous emissions in near future. The electrolytic splitting of water into hydrogen and oxygen can be carried out using for instance electricity generated from renewable energy sources such as solar radiation. Electrolysis processes occurring in electrolyzer cells are complex phenomena and a clear and accurate mathematical representation of the referred processes is vital to accurate predict electrolyzer cells performance. So a comprehensive mathematical model capable of properly describing alkaline electrolyzer cells performance, in terms of efficiency and hydrogen production rate, is proposed in this work. The mathematical model is based on several physical concepts such as energy losses due to electron and ion transfer, entropy increase, electrolyte flow rate, and electrolyzer physical structure and construction material. Compared to existing models, the new proposed one is more complete as it includes more operational parameters (six) affecting cells performance. Once developed, the proposed model has been fine-tuned using experimental data available in literature. The results obtained using the new developed model are in good agreement with Ulleberg’s experimental data. Based on the work carried out here, it is concluded that developing a mathematical model based on physical principles is crucial in the comprehension of electrolysis related processes and how to utilize them in the simplest and most reliable way.