Multi-objective optimization and 4E analyses to simultaneous production of electricity, freshwater, H2 and cooling based on biogas-steam reforming

Abstract

In the current study, a state-of-art biogas-driven poly-generation power plant is presented, evaluated and optimized. For assessing the multi-aspects feasibility of the proposed plant, exergy, energy, exergoeconomic, and environmental evaluations are applied as the robust tolls to the assessment of the plant. Also, to enhance the hydrogen production by the system, the steam reforming technology and proton exchange membrane are incorporated into the plant. Based on the obtained results, the designed plant can generate 86.04 kW, 0.9662 kg/s, 958.2 kW, and 704.573 kg/h of electricity, fresh water, cooling, and hydrogen, respectively. In this plant, the energy efficiency is approximately 33.5%, while the exergy efficiency is about 31.2%. Also, some unit cost of the product and environmental penalty cost rate are calculated at about 23.7 $/GJ and 141.7 $/h. Analyzing sensitivity helps identify which parameters affect the system's performance and determine the most effective optimization mode. The multi-objective optimization mode result improves the exergy and energy efficiencies of the plant by 19.9% and 24.5%, respectively.