A new biomass-natural gas dual fuel hybrid cooling and power process integrated with waste heat recovery process: Exergoenvironmental and exergoeconomic assessments

Abstract

The integration of gas turbine cycle (GTC)-based energy processes with a biomass gasification process employing a post-combustion approach, in addition to improving the reliability and performance of the energy cycle, can reduce the current crisis in the energy sector and balance the environmental impacts of the hybrid energy cycle. The present paper develops a multi-criteria evaluation and optimization of a novel hybrid cooling and power process (HCPP) based on GTC and post-combustion-based biomass gasification process integrated with downstream cycles. Two fuels (i.e., natural gas and biomass) are utilized simultaneously to produce energy in the proposed process. In addition, the downstream cycles are based on two organic Rankine cycles (ORCs) and a refrigeration unit to recover waste heat. The performance of the developed HCPP has been evaluated and discussed from the thermodynamic-conceptual, exergoenvironmental and exergoeconomic points of view. Additionally, a tri-objective optimization is applied to identify optimal inputs and outputs variables. The overall results indicated that the proposed HCPP can produce 13 MW of electric power and 7.6 MW of cooling load. The thermal and exergy efficiencies of the system were 70.1% and 42.85%, respectively. Moreover, the values of levelized cost of energy (LCOE) and product unit environmental impact (PUEI) were calculated as 0.0748 USD/kWh and 0.0184 Pts/kWh, respectively. However, under tri-objective optimization, the values of LCOE and PUEI can be reduced by approximately 9.4% and 16.8%. The effect of different parameters was also discussed and evaluated through a parametric analysis. Furthermore, the conceptual assessment and design of the solar field was developed for a hypothetical scenario and configuration (based on geographical conditions of a certain region).