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arXiv · 2402.14823

Geothermal Energy in Sedimentary Basins: Assessing Techno-economic Viability for Sustainable Development

Abstract

Drilling deep geothermal wells has proven to be a challenging endeavor, primarily due to issues such as loss circulation events, material limitations under high temperatures, and the production of corrosive fluids. Furthermore, the substantial upfront costs, coupled with geological and technical obstacles associated with drilling super-hot EGS wells in igneous rocks, hinder the widespread implementation of geothermal systems. Alternatively, geothermal energy development in sedimentary basins presents an opportunity for clean energy production with relatively lower investment costs compared to the development of super-hot EGS in igneous rocks. Sedimentary basins exhibit attractive temperatures for geothermal applications, and their wide distribution enhances the potential for nationwide deployment. Decades of drilling and development experience in oil and gas wells have yielded a wealth of data, knowledge, and expertise. Leveraging this experience and data for geothermal drilling can significantly reduce costs associated with subsurface data gathering, well drilling, and completion. This paper explores the economic viability of geothermal energy production systems in sedimentary basins. The study encompasses an analysis of time-to-hit-temperature (THT) and cost-to-hit-temperature (CHT) parameters, as well as Favorability maps across the United States. These maps are based on factors such as well depth, total drilling time, well cost, and subsurface temperature data. By integrating sedimentary basin maps and underground temperature maps, the THT and CHT maps can facilitate the strategic placement of EGS wells and other geothermal system applications in the most favorable locations across the United States.

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BibTeXRIS

Orkhan Khankishiyev, Saeed Salehi, Runar Nygaard, Danny Rehg. 2024-02-05. Geothermal Energy in Sedimentary Basins: Assessing Techno-economic Viability for Sustainable Development. https://arxiv.org/abs/2402.14823

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