Parametric study of a power plant extension system based on solid-oxide electrolyzer cell (SOEC) system was conducted. Parameters involved in the analysis include temperature, amount of exhaust gas recirculation (EGR) and mole flux. Three limiting steps for reactant gases conversion were identified. An attempt has been made to explain the twin effects of EGR on the system performance. Increased performance of CO2 conversion at lower temperatures has been observed. Significant effects of mole flux and temperature on CO2 and H2O conversion have been confirmed. For the system configuration under study, 46.2% of electricity-to-syngas efficiency has been achieved. Maximum CO2 removal performance of similar to 2.57 mol CO2/kWh was predicted at the temperature of 500 degrees C. Conversion ratio of 50-100% of CO2 is achievable depending on the operating conditions. Recommendations have been made for incorporating SOEC system into a power plant to mitigate CO2 and improve efficiency and flexibility of electricity production. (C) 2013 Elsevier Ltd. All rights reserved.