In the context of greenhouse gas emissions reduction, carbon capture and storage (CCS) is considered as a promising option, especially for power plants applications. Three different concepts are mainly investigated; pre-, oxy-fuel and post-combustion capture. For separating the CO2 from the other gases several technologies can be applied such as chemical or physical absorption, adsorption or membrane processes. The technology choice and performance is defined by the gas composition and flowrate, the CO2 concentration, the required CO2 purity and the technology availability. The technology performance is given by the separation efficiency, the thermal and mechanical energy demand and the costs. The aim of this project is to study membrane separation processes for CO2 capture applications and to compare the performance with other technology options for CO2 capture in power plants.