| Summary: | Fuel cells are a promising technology for the production of electricity from hydrogen or other fuels with high efficiency and low emissions. They are suitable for stationary, transportation and portable applications. However, they are still more expensive than existing technologies and there are technical challenges that need to be overcome for their commercialisation. Therefore, accurate and efficient design methodologies for fuel cell systems design are becoming increasingly important. Modelling and optimisation present a great potential to inform fuel cell systems design, which often results in savings in design cycle time and cost, and better design and operation. The purpose of this thesis is to investigate the applicability of model-based design approaches to fuel cell systems design when applied to a single-cell fuel cell, then a fuel cell stack and, ultimately, a system-level fuel cell system, such as a microcogeneration plant. The development of mathematical models for a single-cell fuel cell, a stack and a microcogeneration system is presented in detail. The use of these models in model-based design is then illustrated. For instance, the effectiveness of a conventional humidification design is examined using the single-cell fuel cell model. The fuel cell stack model is used within a multi-objective optimisation framework to investigate how size trades for efficiency. Finally, the micro-cogeneration plant model is used to investigate the trade-off between fuel consumption and electrical power output, compare different micro-cogeneration operating strategies and examine the interaction between operating strategies and electricity network. Overall, when properly formulated and validated, modelling and optimisation are useful tools in fuel cell systems design as they provide means by which engineers can obtain valuable information about the behaviour of the system, make informed decisions, generate different design alternatives and identify good designs even before a prototype is fabricated.
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