Engineering Sustainabilitiy Development and Its Application in Fuel Cell Systems

Fuel cell system is considered as one of the most important sources of clean energy in the near future to meet the challenge of environment friendly global energy demand, however its sustainability as a fuel has not been completely established, including environmental, economical and safety impacts. In this paper, a sustainability analysis is performed for Fuel Cell systems compared with other current and future potential energy sources. Most of the sustainability studies have been concerned so far only with the environmental impact and less rigorous methods have been used in other studies to quantify the sustainability of energy systems. The methodology used in this study ensures a Sustainable Development of a process not only with respect to environmental impact, resource consumption but also with respect to societal and economic impacts. It incorporated indicator-based analysis, which allow provisions for benchmarking for alternative processes and simplifies priorities for several sustainability elements of the processes. Indicators were selected from mostly seen parameters in manufacturing process systems. To integrate those indicators with the Fuel Cell energy systems the formulations were modified to adopt it with the energy systems. Three of the major prospective fuel cell systems PAFC, SOFC and MCFC were considered in this study to compare their sustainability indicators. Some of the difficulties can be encountered to quantify the performance of the systems are due to lack of sufficient process specific data, scarcity of necessary information and satisfy the needs for decision makers. To overcome these difficulties a decision making tool was used to compare and set priorities to these indices of different fuel cell technologies. Since the performance indicators analyzed for this system varied widely, a Multi Criteria Decision Making (MCDM) process was used in this purpose. Analytical Hierarchy Process (AHP) is chosen as a MCMD tool which was applied to compare the indicators of different fuel cell process alternatives under study. The Sustainability indicator priority score and each individual alternative's performance score together are used to determine the most sustainable alternative.