A necessary step toward the deployment of CCUS in the PCOR Partnership region is understanding the magnitude, distribution, and variability of major stationary CO2 sources and potential CO2 storage sites. The PCOR Partnership continues to refine the characterization of sources, geologic storage, and infrastructure within the region. This continued regional characterization is refining CO2 storage resource estimates for the program and providing context for extrapolating the results of the large-scale demonstrations.
Opportunities for the safe, long-term geologic storage of CO2 are found in the deep portions of the extensive sedimentary basins present throughout the PCOR Partnership region.
Although oil was discovered in the PCOR Partnership region in the late 1800s, significant development and exploration did not begin until the late 1920s. Today, oil is drawn from the many oil fields in the PCOR Partnership region at depths ranging from as little as 200 feet (60 meters) below ground level to approximately 5 miles (8000 meters). The body of knowledge gained in the nearly 90 years of exploration and production of hydrocarbons in this region is an important step toward understanding the mechanisms for secure storage of significant amounts of CO2.
Reconnaissance-level CO2 storage estimates were made for selected oil fields in the Williston, Powder River, Denver–Julesberg, and Alberta Basins. The estimates were developed using reservoir characterization data obtained from petroleum regulatory agencies and/or geological surveys from the oil-producing states and provinces of the PCOR Partnership region. Results of the estimates for the evaluated fields (using a volumetric method) in the four basins indicate a CO2 storage potential of over 3.5 billion tons (3.2 Gt) of CO2 while producing an extra 7 billion barrels of oil from existing developed reservoirs.
Deep saline formations within the PCOR Partnership region have the potential to store vast quantities of
anthropogenic CO2. The PCOR Partnership and its partners in Canada have evaluated several saline formations
to determine the magnitude of the CO2 storage resource available. In areas of many sedimentary basins,
more than one geologic layer has the characteristics for safe, permanent CO2 storage: porosity, permeability
, and capacity for storage with an appropriate seal to ensure safe, long-term storage. The basins in the PCOR
Partnership region have many such configurations, called stacked target formations, offering the potential for
geologic storage at many depths from a single surface location. The limiting factors are minimum depth (injected
CO2 is naturally supercritical at 3000 ft) and minimum salinity (to avoid protected groundwater resources).
Reconnaissance-level characterization has identified at least 330 Gt of potential storage in deep saline formations. More detailed characterization activities in the PCOR Partnership region are ongoing.
The PCOR Partnership has identified, characterized, and categorized 458 stationary sources in the region that have an annual output of greater than 100,000 metric tons of CO2. These stationary sources have a combined annual CO2 output of nearly 500 million metric tons (Mt). Although not a target source of CO2 for geologic storage, the transportation sector in the U.S. portion of the PCOR Partnership region contributes nearly an additional 158 Mt of CO2 to the atmosphere every year.
The annual CO2 output from the various large stationary sources ranges from 100,000 metric tons (0.1 Mt) for industrial and agricultural processing facilities that make up the majority of the sources in the region to nearly 18 Mt for the largest coal-fired electric generation facility. Fortunately, many of the large point sources are located in areas that are favorable for CO2 storage because they lie above deep sedimentary basins.
The geographic and socioeconomic diversity of the PCOR Partnership region is reflected in the diversity of the CO2 sources found there. About two-thirds of CO2 is emitted from electricity generation. Significant emissions also result from energy exploration and production activities; agricultural processing; fuel, chemical, and ethanol production; and various manufacturing and industrial activities.
Canadian emissions within the PCOR Partnership region are primarily in Alberta, with extensive use of fossil fuel resources. When compared to total U.S. CO2 emissions, the states in the PCOR Partnership region emit relatively more CO2 from electric utilities and less from industries and transportation.
Although the CO2 emissions from the individual PCOR Partnership point sources are no different from similar sources located around North America, the wide range of source types within the PCOR Partnership region offers the opportunity to evaluate the capture, transport, and storage of CO2 in many different scenarios.
CCUS policy is taking a prominent position in the climate management debate that is occurring at national, regional, and local
levels, and the legal framework for the geologic storage of CO2 continues to evolve.
In areas where extensive oil and gas production activities have taken place (in particular, EOR or acid gas injection), the legal framework is well established for these types of injection activities. In other jurisdictions, less of the legal framework may be in place for geologic storage of CO2. Government organizations—which vary by jurisdiction—may have oversight for various aspects of the CCUS project, including the permitting, construction, health and safety, liability, protection of water supplies, and monitoring. EPA has promulgated rules for various aspects of carbon management and reporting; many states are moving forward with their own rules and regulations to accommodate CCUS projects.
Staying abreast of the latest regulatory developments is of the utmost importance for The PCOR Partnership. Participating in the Interstate Oil and Gas Compact Commission’s (IOGCC’s) Geological CO2 Sequestration Task Force and Pipeline Transportation Task Force, the Groundwater Protection Council’s (GWPC’s) Class VI Workgroup, and the Presidential Interagency Task Force on CCUS allows the PCOR Partnership to provide technical input to State and Federal Policy and Regulations related to CCUS. The PCOR Partnership also provides reviews and comments where appropriate on provincial, state, and federal rule making and reviews enacted legislation.
To facilitate the exchange of information, ideas, and experience among oil and gas regulatory officials, the PCOR Partnership hosts Regulatory Roundup Meetings. The meetings inform regional regulatory officials about the current status and evolving nature of regulations that affect CO2 capture, compression, transport, injection for CO2 storage, or CO2 EOR. These meetings allow for improved coordination of regulatory strategies that will ultimately enhance opportunities for CO2 storage and CO2 EOR in the region.
A number of states have put laws and regulations for CCUS onto the books, including Wyoming, North Dakota, Texas, and Louisiana, to name a few. However, with the publication of EPA’s final rule and guidance documents covering injection wells for geologic storage of CO2, states now have to rewrite their legislation and rules to conform to EPA’s rule.