Final Environmental Impact Assessment of the Innovative Micro-Bio-CHP Fuel-cell Microgeneration System for Multi-family Buildings

Micro-Bio-CHP integrates a biomass updraft gasifier, a combined thermal-catalytic gas-cleaning unit, a solid-oxide fuel cell (SOFC) and a photovoltaic array for multi-family buildings. The system is compared with a pellet boiler, a Stirling-based biomass CHP and a natural-gas SOFC at identical nominal heating capacity, for a representative nine-apartment building. Specific emissions of NMVOC and TSP fall substantially below those of both biomass reference systems and approach those of the natural-gas SOFC. CO emissions are comparable to those of the Stirling-based biomass CHP and roughly one order of magnitude below the pellet-boiler and natural-gas SOFC references, while NOx emissions are reduced relative to both biomass references. Within the applied accounting conventions – including grid-electricity displacement and biogenic-CO2 climate-neutrality accounting for sustainably sourced wood pellets – stock modelling for Germany under a mid-range deployment scenario indicates that Micro-Bio-CHP is the only one of the four options reaching modelled net-negative balances for both total suspended particulates (TSP) and greenhouse gases (GHG) by 2050. Austria shows the same qualitative pattern at smaller absolute scale. The principal optimisation priority is the reduction of fuel demand and the increase of the overall system efficiency.