The potential of a novel multigeneration system based on a biogas-fueled gas turbine: Thermodynamic, exergoeconomic, and multi-objective assessments

A novel multigeneration system is proposed based on a biogas-fueled gas turbine. The proposed multigeneration unit comprises the Biogas-Fueled Gas Turbine (BFGT), the Proton Exchange Membrane (PEM), the Reverse Osmosis (RO) desalination, the Organic Rankine Cycle (ORC), and the Domestic Water Heater (DWH) for power, hydrogen, freshwater, and heating and is examined in terms of thermodynamics and exergoeconomics. A parametric study and multi-objective optimization are also done to assess the changes of the system parameters affecting the performance. Based on results, a thermal efficiency of 62.45 %, an exergy efficiency of 32.52 %, an environmental penalty cost of 1.93 $/hr, and a power specific cost of 28.98 $/GJ are calculated for the system. The parametric study indicates that the thermal and exergy efficiencies, and heating are maximized with the air compressor pressure ratio while the power specific cost, net output power, hydrogen production, and desalinated water have different trends. The resulted optimal designs are promising because they consider both the thermodynamic and exergoeconomic aspects simultaneously. The proposed system can be employed in areas with biomass energy potential that do not have access to the electricity grid to provide electricity, heating, freshwater and clean hydrogen fuel. The results also show that the multigeneration system is better in terms of energy and exergy efficiencies and economic parameters than the simple BFGT. Improvement of thermal efficiency compared to previous studies showcases advancements in methodology used in the current study for the proposed multigeneration system.