National Risk Assessment Partnership
The Need for Quantitative Risk Assessment for Carbon Utilization and Storage
Carbon utilization and storage—the injection of carbon dioxide (CO2) into permanent underground and terrestrial storage sites—is an important part of our nation’s strategy for managing CO2 emissions. However, some hurdles still exist before carbon storage becomes a reality in the U.S. at a large scale.
Of particular relevance to making a business case for large-scale, long-term storage feasibility is the development of quantitative science-based methods for estimating long-term risks.
The National Risk Assessment Partnership Initiative
The National Risk Assessment Partnership (NRAP) is a DOE initiative that harnesses core capabilities developed across the National Laboratory complex, in the science-based prediction of the critical behavior of engineered-natural systems. The NRAP initiative is currently focused in support of the business case for commercial deployment of CCUS.
To assist in effective site characterization, selection, operation, and management, NRAP is considering potential risks associated with key operational concerns, as well as those associated with long-term liabilities. Operational issues include the management of reservoir pressure and stress to avoid conditions that might induce seismic activity. Issues associated with long-term liabilities include groundwater protection and storage permanence to avoid CO2 leakage.
Figure 1. Risk profile curve, similar to Benson, 2004, describing the risks
and associated uncertainties of a storage project over time.
NRAP Products and Expected Benefits
NRAP products for carbon utilization and storage include:
Simulation toolsets and protocols for quantifying storage performance and potential risks.
Broadly applicable quantitative models for predicting the behavior of specific components at a storage site (such as changes in wellbore permeability due to chemical reaction).
A web-accessible database of critical parameters for calibrating models needed to predict CO2 storage and potential risks.
Comprehensive technical assessments of key storage security relationships and issues.
The tools and improved scientific base developed by the collaborative will help operators design and apply monitoring and mitigation strategies. They will help regulators and their agents quantify risks and perform cost-benefit analyses for specific Carbon Capture and Storage (CCS) projects. Finally, financiers and regulators will be able to invest in and approve CCS projects with greater confidence because costs of long-term liability can be estimated more easily and with less uncertainty.
Figure 2. Preliminary results of quantitative assessment of IPCC Storage Goal
of 99 percent retention for a particular site type.