NETL CO2 Injection and Storage Cost Model

Abstract

The U.S. Department of Energy’s National Energy Technology Laboratory (NETL) has developed a model to estimate the costs of sequestering captured CO2. This model includes costs from initial regional geologic evaluation through site characterization, permitting, injection/MVA operations, postinjection site care to final site closure and transfer to long-term stewardship. Differences in storage costs across different geologic formations are driven by two basic factors: injectivity which determines the number of injection wells drilled to accommodate a given rate of CO2 injection and the volume of CO2 to be sequestered which determines, per in-situ reservoir parameters, the areal extent of the plume and hence the Area of Review of a Class VI well permit. The AoR defines the areal extent of MVA activities which dominates costs during injection and post-injection operations. The basic framework for this model provides costs for compliance with various sections of EPA’s Class VI regulation and Subpart RR of the GHG Reporting Program. Cost analysis at two levels is provided by this model: site specific where the modeler can enter their own reservoir and cost data and regional in the form of cost supply curves. A geologic and cost database was developed to support this model. Published analyses of storage cost to date have been very general, providing estimates for site characterization or overall costs but few details. While storage costs are a small percentage of overall CCS costs, they represent a significant investment. Getting to the point of injection operations will take tens of millions of dollars. Model results indicate that operation/post-closure MVA costs will represent some 70 percent of overall storage costs. Also, the financial mechanisms used to establishing Financial Responsibility prior to permitting may represent a significant cost. A detailed understanding of overall storage costs is critical for investors and policy planners. This model can be combined with a simple pipeline costing model that is part of NETL’s current Transport, Storage, and Monitoring Cost Model as well as with NETL’s Capture-Transport-Storage pipeline model capable of modeling CO2 pipeline networks. This model can be combined with NETL’s Power Supply Financial Model for cost analysis across the CCS value chain.