Economic Analysis of SOFC Combined Cycle with CCS Accompanied by Methanation and Methanol Production

In this study, a novel solid oxide fuel cell CO2 capture and utilization co-generation system is discussed. The system uses photovoltaic power to produce hydrogen for methanation reactions and synthesis of methanol to utilize the carbon dioxide captured by the system. The system aims to capture, store, and utilize the carbon dioxide produced by the system when using natural gas to generate electricity, which is zero carbon emission from the power generation system. The process involves separating CO2 from the system's exhaust gas, efficiently capturing and storing it through methanation and methanation. The synthesized methane is utilized for SOFC power generation, while the synthesized methanol is sold commercially. To calculate the economic performance of this system, the discounted cash flow method was used. To evaluate the economics of the system, the system parameters were set to a retail sales price of electricity from the power plant of $0.36/kWh and the rated output of the system was 750 MW, the renewable energy capacity (photovoltaic) of the system at 151.3 MW, the system was set to have a discount rate of 3%, and a 50%-50% reactor share for the synthesis of methane and 50% for the synthesis of methanol. The results of the economic calculations are: the payback period of the system using the simple equilibrium method is 9 years, the NPV is 10 years, and the dynamic payback period considering the NPV and the discount rate is 18.86 years. The integration of SOFC power generation with CO2 utilization and storage through methanation and methanation presents a promising solution for achieving efficient power generation while effectively addressing CO2 emissions. The economic analysis supports the feasibility of the system.