The use of oxy-combustion is an attractive alternative to amine based absorption of CO2 to retrofit coal-fired power plants. The aim of this work is to compare these two carbon capture technologies taking into account environmental and economic criteria. To this end, we have developed a rigorous bi-criteria mixed-integer nonlinear programming (MINLP) model that allows identifying in a systematic and rigorous manner the best pollution control technologies (including carbon capture devices) to be installed in an existing coal-fired plant. We have applied this methodology to a coal-fired power plant of a given capacity. Numerical results indicate that carbon capture with MEA performs better for soft environmental limits while oxy-fuel combustion is the preferred choice when more stringent environmental limitations are considered. (c) 2012 Elsevier Ltd. All rights reserved.