Kentucky Geological Survey completes assessment of Kentucky’s potential for CCS

Kentucky officials, energy companies and researchers have a new resource to help make decisions on management of CO₂ emitted from facilities such as coal-fired electricity plants. The Kentucky Geological Survey (KGS) at the University of Kentucky has completed a broad assessment of geologic factors affecting Kentucky’s potential for permanent storage of CO₂. It also addresses the potential use of CO₂ for increasing recovery of oil from Kentucky fields.

The Kentucky Energy and Environment Cabinet contracted KGS for the study that resulted in the report entitled “Evaluation of Geologic CO2 Sequestration Potential and CO₂ Enhanced Oil Recovery in Kentucky”. Copies were provided to cabinet officials in May and the report is available at the KGS website. Marty Parris, Steve Greb, and Brandon Nuttall of the KGS Energy & Minerals Section were principal investigators, but the study and report received important contributions from other KGS staff.

The report notes that Kentucky’s coal-fired power plants discharged 102.8 million t of CO₂ into the atmosphere in 2005: 95% of the state’s electricity comes from coal-fired power plants, so this issue is particularly important to the commonwealth.

According to the report, previous studies done under the auspices of the Department of Energy estimate that Kentucky can store up to 11.6 billion t of CO₂ in the pore space of underground geologic formations. “This Department of Energy estimate is speculative, however,” says Parris, “and the actual amount of pore space that can be occupied by CO₂ needs further scientific confirmation. In addition, the viability of carbon storage will be affected by engineering considerations, economics, and regulatory policies.” The report examines five topics:

1. The concept and strategy behind geologic CO₂ storage and the information needed to appropriately assess its potential. This overview examines the properties of CO₂ when stored deep underground, the geologic formations in which it can be stored, and how much pore space will be needed for industrial-scale geologic carbon storage.
2. A geologic evaluation of using CO₂ for enhancing the recovery of oil from Kentucky fields. Though CO₂ has been used to enhance oil recovery in other parts of the US since the early 1960s, the technology has little precedent in Kentucky.  KGS staff evaluated the conditions in 70 oil reservoirs for their suitability for enhanced oil recovery.
3. The analysis of subsurface formation-water chemistry and its implications for CO₂ storage. KGS used data from 356 water analyses from oil and gas reservoirs to examine flow and chemical processes in the subsurface and to estimate the amount of CO₂ that can be dissolved in the formation waters thousands of feet below potable groundwaters.
4. Evaluation of CO₂ storage potential, particularly along some of the state’s river corridors where coal-fired power plants are located. This portion of the report provides information on the deep rock units (more than 2500 ft below the surface) that may have carbon-storage capacity or may serve as seals to help keep stored CO₂ in place. Deep rock units are estimated to have 2.6 to 10.6 billion t of storage capacity, but capacity is not equally distributed around the state, and a few rock units comprise the bulk of the capacity.
5. Geologic evaluation of CO₂ storage potential for 23 sites nominated for coal-to-liquids installations. These were sites identified by the state as “locations appropriate for deployment of next-generation coal-based industries that would include possibilities for sequestering carbon emissions,” according to the report.

“Addressing the technological, economic, legal and policy issues of CO₂ capture and storage is of extreme importance for Kentucky and the nation as a whole,” said Len Peters, secretary of the Energy and Environment Cabinet. “This document is a key piece in the equation because it gives us significantly more information on various aspects of geologic storage of CO₂, as well as enhanced oil recovery, and the potential viability of both in the commonwealth. We will be using the information in this document to help us achieve the goals of managing CO₂ as outlined in Governor Beshear’s comprehensive energy plan to ensure that we can continue to use our abundant coal resources in a carbon-constrained world.” 

The report provides basic information to help the state, industry and others make decisions concerning potential for geologic carbon storage in Kentucky in the future. It concludes that more research through demonstrations and pilot projects is needed to understand the state’s carbon storage potential and to reduce the risks when implementing commercial-size carbon storage projects.

The publication is being provided free of cost through the KGS website

Read the article online at: https://www.worldcoal.com/coal/15062010/kentucky_geological_survey_completes_assessment_of_kentucky%E2%80%99s_potential_for_ccs/