Thermo-economic and environmental analysis of integrated power plant with carbon capture and storage technology

Abstract

The thermo-economic and environmental analysis of an integrated power system with carbon capture and storage was investigated. The plant comprises solid oxide fuel cell (SOFC), gas turbine (GTC), steam turbine (STC), organic Rankine (ORC), absorption refrigeration (ARC), and carbon capture and storage (CCS) technologies. The system was modelled in terms of energy, exergy and economics, and implemented in the Engineering Equation Solver and MS Excel spreadsheet. Key results show that net power is 147.2 MW, with energy and exergy efficiencies of 40.2 and 39.9%, respectively. A total exergy destruction rate of 217.4 MW is obtained, and distributed as 38, 18, 14, 13, 10, and 7%, respectively, for gas turbine, SOFC, ARC, CCS, ORC and STC. The study further propose that 96.7% of carbon dioxide (CO2) can be captured from the flue gases, and 807.3 kton of CO2 can be transported to depleted oil reservoirs annually for enhanced oil recovery. Cost analysis suggests that the plant's total cost, including the cost of transporting and storing CO2, is $ 186 million and cost of CO2 avoidance is $ 110 per tonne, while the levelized cost of energy and payback on investment are put at $ 0.123 per kWh and 5.2 years, respectively. Parametric simulation of pressure ratio, SOFC temperature, fuel utilization factor, excess combustion air, length of pipeline and interest rate were also investigated. The study has the potentials of pushing the energy policy landscape of an energy disadvantaged economy into a broader energy access and climate action terrains.