Returns to Scale in Carbon Capture and Storage Infrastructure and Deployment

Abstract

The degree to which carbon capture and storage (CCS) is deployed will be partly determined by the returns to scale of the technological system that captures, transports, and stores carbon dioxide (CO2). This technological system spatially connects the organization of CO2 point sources with the organization of geologic CO2 storage reservoirs. These point sources and storage reservoirs are heterogeneous in the amount of CO2 that they produce or store and in the costs of capturing or storing CO2, and the associated cost structures interact to determine the returns to scale for the entire coupled system. The SimCCS cost-minimizing geospatial deployment model is used to deploy CCS for a variety of combinations of CO2 sources and injection reservoirs and determine the returns to scale for CCS deployment and unravel the determinants thereof. SimCCS minimizes the total costs of the entire capture, transport, and storage system by simultaneously determining how much CO2 is captured from each source, how much CO2 is stored in each storage reservoir, and assigning CO2 flows through pipeline networks that include trunk distribution lines that are routed to minimize the influence of the social and physical topography. The returns to scale for the entire CCS system involves the interaction of the cost structures for each link in the CCS chain — capture at the source, transport through the network, and storage at the reservoir — each of which is modeled with cost structures that allow for increasing returns to scale. While it is possible that these cost structures can reinforce each other, the variability of source and reservoir costs and capacities interact with the spatial organization of sources and reservoirs to limit and ultimately reverse the returns to scale for CCS as the scale of the system expands.