Carbon capture and storage (CCS) has been an energy industry practice for decades, originating as a mechanism to enhance oil and gas recovery. But carbon dioxide gas is tricky to capture, and even trickier to store: Without airtight sealants and careful monitoring, the gas seeps up through cracks in the subsurface and quickly reenters the atmosphere. But what if the carbon dioxide could be instead stored as rock?
This assessment was conducted to fulfill the requirements of section 712 of the Energy Independence and Security Act of 2007 and to contribute to knowledge of the storage, fluxes, and balance of carbon and methane gas in ecosystems of Alaska. The carbon and methane variables were examined for major terrestrial ecosystems (uplands and wetlands) and inland aquatic ecosystems in Alaska in two time periods: baseline (from 1950 through 2009) and future (projections from 2010 through 2099). The assessment used measured and observed data and remote sensing, statistical methods, and simulation models. The national assessment, conducted using the methodology described in SIR 2010-5233, has been completed for the conterminous United States, with results provided in three separate regional reports (PP 1804, PP 1797, and PP 1897).
In recent years, carbon capture and storage (CCS) has been advocated as a means to continue using fossil fuels until carbon-free energy systems are developed while at the same time reducing anthropogenic carbon emissions (IPCC, 2005). CCS entails capturing carbon dioxide (CO2) from fossil fuel combustion and sequestering it from the atmosphere for thousands to hundreds of thousands of years. Storage can be accomplished through mineral carbonation, ocean storage, biological storage, or geologic storage. For a variety of reasons, geologic carbon sequestration (GCS) is the technology that can be deployed in the shortest timeframe while capturing significant amounts of CO2.
Given the wide range of stakeholders this publication is intended for and its broad subject matter, it is unlikely that any one reader will be well versed in all topics. Thus, this report has introductory material incorporated into each content area to guide the reader through these possibly unfamiliar subjects. For example, in discussing the chemistry of CO2, phase diagrams are explained, so the discussion of the phase relations of injected CO2 and its implications for project design, safety, and monitoring can be understood by the non-specialist. Likewise, the regulatory section provides an overview of environmental laws before investigating the details of the Safe Drinking Water Act’s UIC program. Equipped with this background information readers can effectively assess the various claims and counterclaims about CCS.
"Unconventional reservoirs" for carbon dioxide (CO2) storage—that is, geologic reservoirs in which changes to the rock trap CO2 and therefore contribute to CO2 storage—including coal, shale, basalt, and ultramafic rocks, were the focus of a U.S. Geological Survey (USGS) workshop held March 28 and 29, 2012, at the National Conservation Training Center in Shepherdstown, West Virginia. The goals of the workshop were to determine whether a detailed assessment of CO2 storage capacity in unconventional reservoirs is warranted, and if so, to build a set of recommendations that could be used to develop a methodology to assess this storage capacity. Such an assessment would address only the technically available resource, independent of economic or policy factors. At the end of the workshop, participants agreed that sufficient knowledge exists to allow an assessment of the potential CO2 storage resource in coals, organic-rich shales, and basalts. More work remains to be done before the storage resource in ultramafic rocks can be meaningfully assessed.
The objective of this report is to provide basic technical information regarding the CO2-EOR process, which is at the core of the assessment methodology, to estimate the technically recoverable oil within the fields of the identified sedimentary basins of the United States. Emphasis is on CO2-EOR because this is currently one technology being considered as an ultimate long-term geologic storage solution for CO2 owing to its economic profitability from incremental oil production offsetting the cost of carbon sequestration.
This report describes the design and performance of the surface equipment used for CO2 storage and injection during the Midwest Geological Sequestration Constortium (MGSC) Validation Phase (Phase II) enhanced oil recovery (EOR) pilot test at the Mumford Hills, Indiana, test site (EOR II) from September 2009 through December 2010 and at the Sugar Creek, Kentucky, test site (EOR III) from May 2009 through May 2010. A total of 6,950 tons (6,300 tonnes) of CO2 were injected at the Mumford Hills site, and a total of 7,230 tons (6,560 tonnes) of CO2 were injected at the Sugar Creek site. The CO2 storage and injection equipment performance, design capacity, and lessons learned for both sites are presented and discussed in this report.