System concept and process layout for a micro-CHP unit based on low temperature SOFC

Abstract

Anode Supported Cells (ASC) are considered as a promising SOFC technology for achieving higher power densities at significantly reduced operating temperatures. Thereby it is commonly expected to enhance both the profitability and durability of fuel cell systems in real world applications. In the collaborative project LOTUS a micro-CHP system prototype will be developed and tested based on a novel ASC technology with an operating temperature of 650°C. The consortium gathered to work in this project incorporates a number of leading European SOFC-developers, system integrators and research institutes, namely the companies of HyGear Fuel Cell Systems (NL), SOFCPower (IT) and Domel (SLO) as well as the Fraunhofer IKTS (D), the EC Joint Research Centre (NL) and the University of Perugia (IT). Th e project is funded under EU 7th Framework Programme by the Fuel Cell and Hydrogen Joint Undertaking (FCH-JU), grant agreement No. 256694. In the first project phase the principle system design was developed strictly following a topdown approach based on a system requirements definition, a model based evaluation of applicable system concepts and a final process definition based on layout calculations and parameter studies. The Fraunhofer IKTS was leader of the work package system design and modeling. In the second phase of the project all required components and submodules are developed with respect to the given process design parameters. The core SOFC stack module with an operating temperature of 650°C will be provided by SOFCPower incorporating enhanced ASCs that are newly developed with support of the University of Perugia. A compact fuel processing module will be developed by HyGear based on air enhanced steam reforming and also enabling for a controllable proportional stack-internal reforming. The advanced fuel processing concept leads to a higher electrical efficiency and a variable power to heat ratio of the system, which is adjustable independently from the electric power output level. A novel exhaust suction fan with a significantly reduced power demand during all operational stages will be provided by Domel for system integration. Finally, in the third phase of the project, the setup and commissioning of the system prototype will be carried out, supported by a model based control logic development and failure mode analysis. The testing procedures, data analysis an d performance evaluation will be monitored by the EC Joint Research Centre