Comparison analysis of hydrogen addition into both anode and afterburner of fuel cell incorporated with hybrid renewable energy driven SOFC: An application of techno-environmental horizon and multi-objective optimization

Abstract

In order to mitigate environmental issues raised by fossil fuel plants, the application of novel technologies driven by clean resources is essential for electricity generation. The fuel cells, in this respect, are of extreme importance; among them, SOFCs are the most proper ones for large-scale power generation plants. The SOFCs, when integrated with biomass gasification, represent a clean, efficient alternative. However, the low hydrogen content of fueling synthesis gas may be challenging. To mitigate this challenge, the present research aims to supply pure hydrogen to be mixed with synthesis gas before entering the anode compartment of SOFC. Wind energy is employed to take advantage of renewable energy for green hydrogen production to produce the required pure hydrogen. Feasibility assessment of a considered novel hybrid electricity generation system is carried out based on thermodynamics laws. Its performance characteristics are compared with a typical biomass-driven SOFC power block. Also, environmental considerations to specify the CO2 emission status of the hybrid plant were taken into account. The results show that with increasing current density, the maximum power values are calculated to be around 267 kW and 283 kW, respectively. Also, the hydrogen-injected framework produces more electricity by 5%–6%, which depends on operating conditions. Such a power generation enhancement has led to greater values for exergetic efficiencies as well as lower values for environmental damage impacts for the novel hybrid structure compared to a typical biomass-driven SOFC unit. Optimization results indicate that at point B, the W˙net and εed respectively become, 330 kW and 0.9.