Analysis of the performance of the first biogas-fed SOFC plant in Europe (the DEMOSOFC project)

In a period of increasing awareness about climate changes and environmental protection, it is important to focus on the development of cleaner energy sources, to reduce the environmental impact of fossil fuels combustion plants. One of the possible solutions is the use of biofuels-fed high efficiency and zero emissions cogeneration systems like fuel cells. The purpose of this thesis is to study the performance of the Solid Oxide Fuel Cell (SOFC) cogeneration plant installed in the framework of the DEMOSOFC European project. The modules are based on the SOFC technology and are fed by biogas locally produced by the SMAT wastewater treatment plant in Collegno, Italy. The system is producing electricity and heat, 100% self-consumed within the plant. The work analyses the electric and thermal performance of the first two SOFC modules (of 58 kW and 45 kW each) after one complete year of operation, as well as the effectiveness of the biogas cleaning unit and the heat recovery system. Data recorded by the numerous operating sensors onsite are collected and elaborated, to evaluate the plant according to a list of selected Key Performance Indicators. The SOFC modules demonstrated to be very effective with an average yearly electric efficiency of ~48% (from compressed biogas to AC power) and a thermal efficiency of ~33%, but technical and logistic problems not directly connected to the modules imposed long periods of stop. The two SOFC modules worked for a total of 3973 hours over the entire year of operation, producing 176.75 MWh globally.