This two part-paper investigates the performance of SEWGS (Sorption Enhanced Water Gas Shift), an innovative reactor for CO2 capture, applied to an Integrated Gasification Combined Cycle (IGCC). In part-A, different SEWGS working conditions are investigated outlining several advantages and performance differences. A comparison of two sorbents is also performed. Part B presents the economic assessment of the investigated SEWGS cases together with the reference plants selected for electricity production. Both pulverized coal and integrated gasifier combined cycle were introduced as reference technologies. Results show that with the base sorbent performances the calculated cost of CO2 avoided is about 30(sic)/t(CO2), which is lower than IGCC with CO2 capture via Selexol and pulverized coal with amine scrubbing. SEWGS allows reducing investment costs, thanks to the simultaneous CO2 and H2S separation, and efficiency penalties compared to Selexol. The adoption of a sorbent with improved performances further reduces the cost of CO2 avoided down to 23 (sic)/t(CO2): advantages of new sorbent are both in terms of equipment savings and lower efficiency penalty. The optimal SEWGS carbon capture rate is between 95% and 98%. Sensitivity analysis on SEWGS equipment cost showed that increasing investment cost of 50%, the impact on cost of CO2 avoided would be minimal, about 3 (sic)/t(CO2). This activity was carried out under the FP7 project CAESAR financed by the EU community. (C) 2012 Elsevier Ltd. All rights reserved.