An exergy analysis is conducted of a gas-fired CO2 capture process based on monoethanolamine (MEA) absorption technology. It is shown that with a combination of AspenPlus and ExerCom, it is possible to get a reasonable result for the exergy loss per unit operation. To enable this, certain modifications were made in the thermodynamics of the reaction of CO2 with MEA. In this reaction, ionic species are formed and an approach enabling the use of electrolytes is necessary. The results show that the major sources of exergy loss are the absorber, the flasher and the flue gas blower. (C) 2004 Elsevier Ltd. All rights reserved.