Development and Analysis of a Novel Multi-Generation System Fueled by Biogas with Smart Heat Recovery

This paper presents a novel multi-generation system based on biogas fuel for simultaneous production of goods such as electricity, cooling, freshwater, and hydrogen using smart heat recovery of combustion gases. The performance of the proposed system is investigated in terms of the first and second laws of thermodynamics. Also, to acquire a comprehensive evaluation of operation costs, an exergoeconomic analysis has been performed. Furthermore, a comprehensive parametric study has been conducted to understand the behavior of the system performance parameters with the design parameters. In the following, to show the superiority of using a Stirling engine, the investigation of the present study is performed under two different scenarios. The proposed system could produce 986 kW, 137.5 kW, 8.39 m3/h, and 2.96 kg/h, net output electricity, cooling load, distilled water, and hydrogen while working with the Stirling engine. In this case, the energy and exergy efficiencies of the proposed system are obtained at 37.3% and 32.08%, which are improved by about 2.96% and 7.89%, respectively. In terms of cost metrics, the total unit cost of the products is about 0.1086$/kWh which has increased by 8.1% compared to the non-sterling engine mode.