Thermo-Economic Analysis of Solid Oxide Fuel Cell Fuelled with Biomass from Human Waste

Abstract

Thermo-economic analysis of solid oxide fuel cell fuelled with biomass from human waste is a research work aimed at generating more hydrogen gas via simulation as fuel from producer gas contained in the biomass of human waste to fuel solid oxide fuel cell for 200kW power generation. Thermolib 5.4 one-month trial version, a MATLAB/Simulink’s was used for simulating the configuration drawn for the two adapted processes. From the simulated result, the energy analysis revealed that producer gas gasification had a thermal efficiency of 82.2% while that of producer gas slow pyrolysis was 34.69% owing to the lower heating value of both gases calculated to be 113.1414kJ/mole (gasification) and 466.3725kJ/mole (slow pyrolysis). The exergy efficiency indicates that for both processes, auto-thermal reformer had an efficiency of 99.7092% (gasification) and 99.645% (slow pyrolysis) while that for solid oxide fuel cell indicates that the producer gas gasification had an efficiency of 57.5937% and producer gas slow pyrolysis 72.4978%. The cost analysis indicates that the total annual cost of $204,947 for producer gas slow pyrolysis configuration is more expensive as compared to that of producer gas gasification configuration where the total annual cost is $133,560. Thus, for the set targeted 200kW power generation; the exergy performance of the solid oxide fuel cells supports the claims that carbon monoxide is also a fuel for the equipment alongside hydrogen gas that was the main fuel to be generated. Producer gas gasification was more efficient due to its low lower heating value and a lighter hydrocarbon content (methane) while that of slow pyrolysis for the set power was not because of the higher energy content of the gas (lower heating value) which implied that the gas had a high capacity of generating more power higher than 200kW