Feasibility analysis of polymer electrolyte fuel cells for residential cogeneration applications in Australia

The objective of the thesis is to identify the technology and determine the economic feasibility for the implementation of the PEFC (Polymer Electrolyte Fuel Cell) stacks for Distributed generation in Australia. The disposition of the thesis starts with an introductory background that highlights the need for a distributed energy system where Hydrogen acts as the main energy source. Subsequently a detailed survey of the availability of various types of fuels for the fuel cell powered stand-alone micro-grid is presented. The different types of fuels considered during the study include natural gas, methanol, ethanol, liquefied petroleum gas (LPG) and diesel. Both the availability and transport aspects for different fuels are surveyed. The coverage domain and the stage of development of the fuel infrastructure vary with its type. The economic feasibility is determined by following a specified set of algorithm which consists of a series of calculations for varying system configurations. The configuration setup varies with the positioning and sizing of the system components like the fuel cell stack, the fuel reformer and the Combined Heat and Power (CHP) distribution network. The cost parameters and operating life for different configurations considered during the analysis are evaluated and then compared to the benchmark case where the power is bought from the grid and the heat demands are met by the conventional gas burner setup. Two different cost approaches have been used; first one where the benefits of scaling up the system are considered and the latter one where a linear system cost approach has been used. Examining the two cost approaches, it is observed that it is important to consider the beneficial scaling factors. The calculated results are considered for two different supply strategies. In the first strategy, the entire heating load of the utility is met by the fuel cell system. Whereas in the second strategy, the heat demand is partly met by the fuel cell system and the gas burner acts as an auxiliary heat source. A software tool in Visual Basic editor linked to a Microsoft excel sheet has been developed for calculations with varying heat and power demands, the three system architectures, and the type of fuel used. Subsequently an analysis on the effects of economic factors has been carried out with the help of the Visual Basic tool mentioned earlier. The results indicate that the different system architectures are suited in various scenarios and the amount of heat and power loads. The results also show that the price of power from the grid has to increase considerably where the fuel cell systems can compete economically with the benchmark case. If a fuel cell system is to be installed, considerations have to be given to the desired economic configuration, the actual heat and power load curves for a domestic utility, costs and availability of the fuel supply infrastructure. The calculated results highlight significant variation in the fiscal and utilization costs for the different combinations calculated in the study