Realising Reliable, Durable, Energy Efficient and Cost Effective SOFC Systems (Real-SOFC)
✍ Scribed by P. Holtappels; R. Steinberger-Wilckens
- Book ID
- 102217039
- Publisher
- John Wiley and Sons
- Year
- 2009
- Tongue
- English
- Weight
- 82 KB
- Volume
- 9
- Category
- Article
- ISSN
- 1615-6846
No coin nor oath required. For personal study only.
✦ Synopsis
Stationary applications of fuel cells, which are considered the prime solid oxide fuel cell (SOFC) market, require long lifetimes in the order of ten years and more. Whilst the engineering problems of designing and building SOFC systems for small and medium scale Combined Heat and Power generation (CHP) generally appear to be solvable (compare especially the Siemens, CFCL and HEXIS developments in the past years), the problem of system performance degradation still constitutes a dramatic challenge for the market entry of SOFC technology. Failing to meet the aim of securing 40,000 to 150,000 hrs of total lifetime will in the medium term eliminate the chance of market access for SOFC technology in stationary applications. Solutions can mainly be sourced in finding new and modifying existent materials capable of withstanding the operating conditions over longer time periods. Long-term stable operation is not the sole goal, though, since reliable operation under everyday conditions also requires 'robustness' of the technology. Reliable operation of fuel cell components will therefore necessitate thermal, load and (in the case of SOFC) redox cycling, operation at optimised efficiencies (high fuel utilisation) and with a variety of fuels, including naturally occurring fuel contaminants.
The European Integrated Project Real-SOFC ("Realising Reliable, Durable, Energy Efficient and Cost Effective SOFC Systems") joined 26 partners from the European fuel cell industry, research institutions and universities in a joint effort to understand and reduce degradation in SOFC. Within the 6 th Framework Programme, Real-SOFC was one of the first so-called 'Integrated Projects' aiming at integrating a comparatively high number of partners into ambitious and multifaceted projects. From 2004 to 2008 the project looked into improving the understanding of degradation processes and simultaneously using that knowledge in developing improved materials and concepts resulting in extended lifetime of stacks. Two 'new generations' of components were obtained and then produced by the industrial and manufacturing partners as industrial-standard components for iterative testing, thus completing two cycles of improvements. The overall goal was to prove reliable lifetime of stacks of well above 10 000 hours in order to qualify these for stationary applications.
Further attention was given to the 'robustness' of stacks, referring to increasing the tolerance towards sulphur content in the fuel, for thermal and redox cycling, and extending operation towards lower steam to carbon ratios -all of which worked towards simplifying the operation of SOFC systems and improving the 'ruggedness' of stacks under transient and sub-optimal conditions that may arise in everyday operation.
Degradation in fuel cells, besides the influence of external incidents and malfunctions, is predominately attributed to the unfavourable long-term behaviour and interaction of materials. Therefore a project like Real-SOFC has a strong emphasis on materials development. The topics covered in the project specifically included the following essential properties of SOFC materials: