Economic optimization and comparative environmental assessment of natural gas combined cycle power plants with CO2 capture

There is a growing concern about environmental issues related to power generation systems. Particularly, natural gas power plants contribute to a significant portion of the global energy market and therefore have attracted considerable attention. Despite extensive literature in the field of analysis of natural gas combined cycle power plants with CO2 capture, there are still some gaps on the relative environmental impacts of different types of plants such as the unknown influence of the CO2 capture material and the implementation of organic Rankine cycles (ORCs). In this paper, 11 alternatives of natural gas combined cycle power plants based on post-combustion, pre-combustion or oxy-fuel combustion CO2 capture with monoethanolamine (MEA) or activated methyldiethanolamine (a-MDEA) and potential ORC implementation were simulated, economically optimized and environmentally assessed to shed light on these gaps. The results show the important role of thermodynamic efficiency in the system's environmental performance. The system based on post-combustion CO2 capture with a-MDEA and ORC showed a superior economic profile as well as a better environmental performance in terms of climate change and fossil resource depletion.