The carbon capture and utilization (CCU) system can be divided into four sub-systems: [NGCC + MEA], [NGCC + PSA], [Reforming + FT] and [Reforming + MS]. Table lists the input and output for sub-systems. The input of a sub-system contains the decision variables and relevant variables from other sub-system. The output of a sub-system contains its mass and energy balance. After the decision variables θ = [θ !:' , θ ;"'< , θ ;"'7 , z =9 , θ =9 , θ !" , ϵ, ε] are given a set of values, the mass and energy balance of the whole CCU system can be assembled from the sub-systems. E ?1##@!:' : net electricity output for [NGCC + MEA] sub-system, netMW.