Design and development of the 5 kW SOFC system

'Full text:' The 5 kW SOFC system has been under development at Fuel Cell Technologies Ltd. (FCT) since 2001. The power output and thermal capacity were chosen after considering typical load data for residential, remote and small commercial applications. A specification for a system was developed in conjunction with target market customers, and much useful feedback into the operability, reliability and maintainability of the system was incorporated. A single prototype was designed and built in 2002 utilizing tubular cells manufactured by Siemens Westinghouse Power Corporation (SWPC). FCT was responsible for system integration and Balance of Plant while SWPC was responsible for the generator which incorporated the cell stack, recuperator, insulation systems and reformer. This prototype was successfully tested at FCT in 2002 and was rapidly followed by four first generation or 'Alpha' demonstration units. The design methodology for the 5 kW system will be described, including the testing carried out to verify performance and reliability of the various subsystems. Results of safety and reliability analyses will also be included leading to an overall description of the design. In the presentation, the performance and design of these first generation units will be described. We will also present some site operating results. As this program was being completed, the second generation or 'Beta' unit was being designed and developed at FCT, with the goal of incorporating the lessons learned on site. This improved unit will be described and the results of early demonstration results of the Beta units will be incorporated into the presentation. It is anticipated that this will show the improved performance of a highly reliable and safe combined heat and power SOFC system. (author)