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Risk assessment as a framework for decisions

Mckenna, Sean A.; Borns, David J.

The risk assessment approach has been applied to support numerous radioactive waste management activities over the last 30 years. A risk assessment methodology provides a solid and readily adaptable framework for evaluating the risks of CO2 sequestration in geologic formations to prioritize research, data collection, and monitoring schemes. This paper reviews the tasks of a risk assessment, and provides a few examples related to each task. This paper then describes an application of sensitivity analysis to identify important parameters to reduce the uncertainty in the performance of a geologic repository for radioactive waste repository, which because of importance of the geologic barrier, is similar to CO2 sequestration. The paper ends with a simple stochastic analysis of idealized CO2 sequestration site with a leaking abandoned well and a set of monitoring wells in an aquifer above the CO2 sequestration unit in order to evaluate the efficacy of monitoring wells to detect adverse leakage.

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Storing carbon dioxide in saline formations : analyzing extracted water treatment and use for power plant cooling

Kobos, Peter H.; Roach, Jesse D.; Klise, Geoffrey T.; Krumhansl, James L.; Dewers, Thomas D.; Heath, Jason; Dwyer, Brian P.; Borns, David J.

In an effort to address the potential to scale up of carbon dioxide (CO{sub 2}) capture and sequestration in the United States saline formations, an assessment model is being developed using a national database and modeling tool. This tool builds upon the existing NatCarb database as well as supplemental geological information to address scale up potential for carbon dioxide storage within these formations. The focus of the assessment model is to specifically address the question, 'Where are opportunities to couple CO{sub 2} storage and extracted water use for existing and expanding power plants, and what are the economic impacts of these systems relative to traditional power systems?' Initial findings indicate that approximately less than 20% of all the existing complete saline formation well data points meet the working criteria for combined CO{sub 2} storage and extracted water treatment systems. The initial results of the analysis indicate that less than 20% of all the existing complete saline formation well data may meet the working depth, salinity and formation intersecting criteria. These results were taken from examining updated NatCarb data. This finding, while just an initial result, suggests that the combined use of saline formations for CO{sub 2} storage and extracted water use may be limited by the selection criteria chosen. A second preliminary finding of the analysis suggests that some of the necessary data required for this analysis is not present in all of the NatCarb records. This type of analysis represents the beginning of the larger, in depth study for all existing coal and natural gas power plants and saline formations in the U.S. for the purpose of potential CO{sub 2} storage and water reuse for supplemental cooling. Additionally, this allows for potential policy insight when understanding the difficult nature of combined potential institutional (regulatory) and physical (engineered geological sequestration and extracted water system) constraints across the United States. Finally, a representative scenario for a 1,800 MW subcritical coal fired power plant (amongst other types including supercritical coal, integrated gasification combined cycle, natural gas turbine and natural gas combined cycle) can look to existing and new carbon capture, transportation, compression and sequestration technologies along with a suite of extracting and treating technologies for water to assess the system's overall physical and economic viability. Thus, this particular plant, with 90% capture, will reduce the net emissions of CO{sub 2} (original less the amount of energy and hence CO{sub 2} emissions required to power the carbon capture water treatment systems) less than 90%, and its water demands will increase by approximately 50%. These systems may increase the plant's LCOE by approximately 50% or more. This representative example suggests that scaling up these CO{sub 2} capture and sequestration technologies to many plants throughout the country could increase the water demands substantially at the regional, and possibly national level. These scenarios for all power plants and saline formations throughout U.S. can incorporate new information as it becomes available for potential new plant build out planning.

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A life cycle cost analysis framework for geologic storage of hydrogen : a scenario analysis

Lord, Anna S.; Kobos, Peter H.; Borns, David J.

The U.S. Department of Energy has an interest in large scale hydrogen geostorage, which would offer substantial buffer capacity to meet possible disruptions in supply. Geostorage options being considered are salt caverns, depleted oil/gas reservoirs, aquifers and potentially hard rock cavrns. DOE has an interest in assessing the geological, geomechanical and economic viability for these types of hydrogen storage options. This study has developed an ecocomic analysis methodology to address costs entailed in developing and operating an underground geologic storage facility. This year the tool was updated specifically to (1) a version that is fully arrayed such that all four types of geologic storage options can be assessed at the same time, (2) incorporate specific scenarios illustrating the model's capability, and (3) incorporate more accurate model input assumptions for the wells and storage site modules. Drawing from the knowledge gained in the underground large scale geostorage options for natural gas and petroleum in the U.S. and from the potential to store relatively large volumes of CO{sub 2} in geological formations, the hydrogen storage assessment modeling will continue to build on these strengths while maintaining modeling transparency such that other modeling efforts may draw from this project.

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A Life Cycle Cost Analysis Framework for Geologic Storage of Hydrogen

Lord, Anna S.; Kobos, Peter H.; Borns, David J.

Large scale geostorage options for fuels including natural gas and petroleum offer substantial buffer capacity to meet or hedge against supply disruptions. This same notion may be applied to large scale hydrogen storage to meet industrial or transportation sector needs. This study develops an assessment tool to calculate the potential ‘gate-to-gate’ life cycle costs for large scale hydrogen geostorage options in salt caverns, and continues to develop modules for depleted oil/gas reservoirs and aquifers. The U.S. Department of Energy has an interest in these types of storage to assess the geological, geomechanical and economic viability for this type of hydrogen storage. Understanding, and looking to quantify, the value of large-scale storage in a larger hydrogen supply and demand infrastructure may prove extremely beneficial for larger infrastructure modeling efforts when looking to identify the most efficient means to fuel a hydrogen demand (e.g., industrial or transportation-centric demand). Drawing from the knowledge gained in the underground large scale storage options for natural gas and petroleum in the U.S., the potential to store relatively large volumes of CO2 in geological formations, the hydrogen storage assessment modeling will continue to build on these strengths while maintaining modeling transparency such that other modeling efforts may draw from this project.

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Results 26–50 of 74
Results 26–50 of 74