Utilization Risk Assessment and Thermal Conductivity Testing for the Low Temperature Geothermal Play Fairway Analysis for the Appalachian Basin

In order to alleviate the large carbon footprint of fossil fuel technology, renewable energy has begun to gain momentum with consumers and industries alike. Geothermal energy has the benefit of providing a reliable energy source with only 5% of the carbon dioxide emissions of fossil fuels, as well as provide a means of carbon sequestration. The application for this energy source is highly dependent on several factors, including reservoir characteristics, temperature, and regional demand. High temperature systems (\u3e150 °C) are best suited for electricity production, while low and medium temperature reservoirs (\u3c90 °C and 90-150 °C, respectively) may be better suited for direct use applications, such as manufacturing purposes or district heating and cooling for commercial and residential areas.;Enhanced, or engineered, geothermal systems (EGS) may provide a means to take advantage of geothermal reservoirs with lower available temperatures. To determine the efficacy of EGS technology in eastern United States, a play fairway analysis was performed on the Appalachian basin. Risk factors examined include thermal resource quality, natural reservoir quality, induced seismicity, and utilization opportunities, which is a focus of this work. Levelized cost of heat, or LCOH, was used to provide a comparison of factors, such as combination of capital costs, operation and maintenance costs, and performance and fuel costs. To determine LCOH, commercial, residential, and infrastructure data were collected from the US Census and fed into GEOPHIRES, a program that uses surface piping, heat exchange equipment (residential and/or commercial), operations, upfront capital cost, and maintenance costs over the lifetime of a 30-year project. The impact of industrial demand on LCOH, such as process heating and cooling and HVAC, for dairy, wood drying, and paper mills were also examined.;Heat flow estimates are equally important in the selection of potential geothermal sites. Estimation of the temperature-at-depth uses heat flow, which is dependent on factors including geothermal gradient and thermal conductivities. Thermal conductivity is a function of depth and position, and for some models is calculated as a weighted average based on thicknesses of lithographic layers. Obtaining actual thermal conductivities can be challenging, and often require the use of databases to predict the geographic variation. For this project, thermal conductivities from Marion County well #244 rock cuttings were found using a portable electronic divided bar (PEDB) system and were compared to COSUNA estimates to assess the current model method