Techno-economic analysis of NGCC power plant with monoethanolamine based CO2 capture process: Exploring operational independent integration alternatives

Power plants are currently a major contributor to global CO2 emissions. Although renewable energy-based power generation is growing steadily, it is predicted that the role of natural gas combined cycle (NGCC) plants will continue to play a significant role in electricity production in the future. The use of post-combustion carbon capture technologies to reduce CO2 emissions from these power plants is a promising option. Among various carbon capture options, monoethanolamine solvent based CO2 capture (MEAC) is the most mature and widely used post-combustion technology. In this process, an aqueous solution of monoethanolamine is used to absorb CO2 from flue gas chemically. This research work investigates three different MEAC integrated NGCC power plant configurations by using auxiliary combustors, exhaust gas reuse (EGRu) and exhaust gas recirculation (EGRc) techniques in different combinations. The use of auxiliary combustors with EGRu and EGRc techniques not only allows the overall plant to operate independently but also improves the CO2 capture performance. A techno-economic analysis is conducted to analyze and compare these configurations to an NGCC power plant without CO2 capture. The results demonstrate that the configuration with EGRu incurs the lowest energy efficiency penalty of 11.5% among the MEAC integrated power plant configurations. In contrast, the novel configuration incorporating both EGRu and EGRc achieves the lowest levelized cost of electricity of 71.44 US$/MWhe and the lowest levelized cost of CO2 capture of 41.51 US$/tonCO2. The research in overall provides attractive options for integrating the NGCC power plants with amine-based CO2 capture, while maintaining operational independence.