Operation of a SOFC with MK35x Stacks within a Biomass Micro-CHP System Based on Wood Pellet Gasification

Within the Micro-Bio-CHP project, funded under the Horizon Europe program, an energy supply system for energy autonomous multi-family buildings based on biomass gasification coupled with a SOFC system shall be implemented. In contrast to conventional CHP-solutions, a partial flow of the product gas is extracted from the biomass gasifier and led to the SOFC system for highly efficient electricity production. BIOS Bioenergiesysteme GmbH as the consortium lead operates the CHP plant with its experience in biomass gasification. The aim of the project is to achieve a high fuel utilization of over 75 % and high electric efficiencies on stack level of more than 44 %. Therefore, a stack module from Fraunhofer IKTS with 3x40 cell stacks was integrated into a SOFC system from INERGIO Technology SA, also containing a HCl- and H2S-removal unit from Hysytech S.r.l. The first operation of the coupled systems shows promising results. The targeted quality of the gas was reached and can be converted by SOFC with an electric efficiency at stack level of 45%. An environmental and overall impact assessments will be performed by the institute WIKUE. Although a highly efficient thermal and catalytic tar reforming is achieved through a catalyst developed by Catator AB, a residual benzene fraction can be found in the product gas. Therefore, contamination tests with benzene were conducted on a single stack to evaluate the influence on the performance on a scientific level.