The mathematical formulation for targeting during energy allocation with carbon capture and storage (CCS) is formally developed. For operating-cost optimization with zero excess, it is shown that CCS sources may be regarded as resources with their cost taken as the increment over the non-CCS option. CCS sources along with clean-carbon resources may then be targeted by profile matching with the limiting composite to establish optimal primary cases. The limiting composite curve is itself sacrosanct and obtained by a single computation of the composite table algorithm (CIA) including only non-CCS sources. Carbon emission networks (CENs) are designed by the nearest neighbors algorithm (NNA). A cost criterion is established to determine cost-factor ranges for optimality of the primary cases, and results validated by solving linear programming (LP) and mixed integer linear programming (MILP) formulations. The methodology essentially comprises four distinct stages - targeting, network design, cost analysis, and optimization - with the first two stages not requiring any cost data. (C) 2011 Elsevier Ltd. All rights reserved.