The critical role of monitoring, verification, and accounting for geologic carbon dioxide storage projects

Abstract

A growing concern that increasing levels of greenhouse gases in the atmosphere are contributing to global climate change has led to a search for economical and environmentally sound ways to reduce carbon dioxide (CO 2) emissions. One promising approach is CO 2 capture and permanent storage in deep geologic formations, such as depleted oil and gas reservoirs, unminable coal seams, and deep brine-containing (saline) formations. However, successful implementation of geologic storage projects will require robust monitoring, verification, and accounting (MVA) tools. This article deals with all aspects of MVA activities associated with such geologic CO 2 storage projects, including site characterization, CO 2 plume tracking, CO 2 flow rate and injection pressure monitoring, leak detection, cap-rock integrity analysis, and long-term postinjection monitoring. Improved detailed decision tree diagrams are presented covering the five stages of a geologic storage project. These diagrams provide guidance from the point of site selection through construction and operations to closure and postclosure monitoring. Monitoring, verification, and accounting techniques (both well-established and promising new developments) appropriate for various project stages are discussed. Accomplishments of the Department of Energy (DOE) Regional Carbon Sequestration Partnerships field projects serve as examples of the development and application to geologic storage of MVA tools, such as two-dimensional and three-dimensional seismic and microseismic, as well as the testing of new cost-effective monitoring technologies. Although it is important that MVA and computer simulation efforts be carefully integrated to ensure long-term success of geologic storage projects, this article is limited to a discussion of MVA activities. This article is an extension of a report published in 2009 by the DOE National Energy Technology Laboratory titled, "Best Practices for Monitoring, Verification, and Accounting of CO 2 Stored in Deep Geologic Formations," to which interested readers are referred for

The Geomechanics of CO2 Storage in Deep Sedimentary Formations

“…One promising approach is CO 2 capture and storage (CCS) in deep geologic formations, such as depleted oil and gas reservoirs, unminable coal seams, and deep saline aquifers (Bachu 2008;Benson and Cole 2008;Bickle 2009;Plasynski et al 2011). Geological media suitable for CO 2 storage must have sufficient capacity and injectivity, and must confine, or at least sufficiently delay the lateral or vertical migration of CO 2 to the surface.…”

Evaluating Use of Satellite Observations for Detecting Large CO2 Leaks and Carbon Sequestration Monitoring

“…In conjunction with carbon scrubbing techniques, sequestration could significantly mitigate the emission of carbon-burning power plants. Scrubbing and sequestration could reduce the carbon output of a given carbon-fired plant by 80-90%, and the geologic carbon storage capacity in the US alone is large enough for capture and sequestration to be a long-term (100+ year) method of emission reduction [Plasynski, 2011]. Although properly selected sites are predicted to maintain nearly all of their input carbon even over large time scales, the possibility exists for CO2 migration and eventual leaking [Holloway, 1997].…”

“…Similarly, injection into coal seams displaces the methane gas commonly contained in these formations. Both of these methods, properly applied, may provide a low net cost method of emission reduction in the power-generation sector [IPCC, 2005;Plasynski, 2011]. In the US, oil, gas, and coal reservoirs have an estimated storage capacity of 316 gigatonnes (Gt, 10 12 kg), which at current estimated US point source emission rates would provide 83 years of complete CO2 storage.…”

“…In the US, oil, gas, and coal reservoirs have an estimated storage capacity of 316 gigatonnes (Gt, 10 12 kg), which at current estimated US point source emission rates would provide 83 years of complete CO2 storage. Storage in saline formations, though without an intrinsic economic gain from carbon injection, would provide storage capacity for 867-3320 additional years at the current rate of emission [Plasynski, 2011].…”

“…In addition to reducing the efficacy of the carbon storage method, leakage could have detrimental effects on vegetation and water resources. This possible effect on water quality brings sequestration methods under the purview of the Underground Injection Control (UIC) Program of the United States Safe Drinking Water Act, which further solidifies the demand for a wide variety of monitoring methods [Plasynski, 2011;Little, 2010]. Potential methods for monitoring include well analysis via boreholes and seismic sensors, soil sampling, local atmospheric sampling via eddy covariance towers, and aircraft-borne LIDAR measurements [Bateson et al, 2008].…”