Multi-Period Cost Optimization of Multi-Mode Carbon Capture and Storage Chains

Abstract

A generally applicable multi-period and multi-mode CCS value chain cost model is developed to account for all individual costs and evaluate different options for CCS value chain implementation. The approach followed involves the configuration of a mixed integer linear programming optimization model, in which the objective function is to minimize the total cost of the CCS chain, considering constraints of mass balance, injection wells, intermediate storage sizing, flow and routing. The model functionality is illustrated through a case study based on a Norwegian CCS chain which is assessed for a planning horizon of 30 years, assigned in five-year long intervals. The model adopts the methodology developed previously by the authors for pipeline transport and geological storage of CO₂ and introduces CO₂ ship transport and intermediate storage at two design pressures (7 and 15 bar). It also includes a newly introduced CO₂ conditioning step (compression and liquefaction) and a further injection mode, directly from ship. For the CCS chain analyzed, it is found that higher CO₂ supply provides economy of scale gains, thus lower levelized cost. Pressure design for ship transportation plays a significant role on the cost of the chain with the trade-off between low conditioning costs and higher transport cost. In the Norwegian CCS case analyzed, individual pipelines from a single hub to each storage site are more economical than a single trunk-line with multiple connections to injection sites. Geological storage costs are largely driven by the availability and the operational costs of the individual sites.

Keywords: CCS Chain, CO2 Ship Transportation, MILP Optimization