Geothermal Energy Planning Considerations for Military Operational Energy Demands

Abstract

Contingency locations are temporary military bases that are often established in austere or contested environments. These locations rely heavily on diesel fuel for electrical power, which creates logistical vulnerabilities and increases the risk to personnel conducting fuel resupply missions. While the Department of Defense has made progress in adopting renewable energy technologies, many of these systems remain too large, inefficient, or underdeveloped for widespread use in operational environments. Geothermal energy presents a promising but underexplored alternative for generating reliable, on-site electrical power without the need for continuous fuel resupply. This thesis evaluates the feasibility of geothermal energy systems for military operational energy demands and introduces a modified power planning process that incorporates geothermal considerations. The research focuses on closed-loop geothermal systems, utilizing an example system called the “Mil-Loop”, which is designed to minimize the system surface footprint and support remote installations. The planning process integrates existing geothermal tools, including GEOMAP/TEST for resource estimation and GEOPHIRES for system modeling and performance analysis. The Mil-Loop System Model incorporates each step of the planning process to produce a site-specific power system profile. A case study using site-specific data from Bagram Airfield was used to assess the performance of a hybrid geothermal-diesel power system. The results suggest that geothermal system integration could reduce diesel fuel consumption by up to 42.9 percent over a 40-year site lifecycle. A sensitivity analysis indicates that geothermal system power output, drilling time, and installation costs are the most critical parameters affecting system viability. Advances in drilling technology and heat extraction have the potential to reduce installation costs and timelines, making geothermal more competitive with diesel generation. This thesis also identifies a gap in military energy planning resources, specifically the lack of frameworks that include geothermal options for operational environments. It recommends that the DoD begin integrating geothermal technologies into its energy planning strategies and develop modular systems that can be deployed in contested or resource-constrained areas. While this research is limited by simplified power demand modeling and generalized tool assumptions, it offers a practical framework for evaluating geothermal viability in future defense applications. This study demonstrates that geothermal energy systems, particularly closed-loop configurations, can serve as a viable and strategically beneficial power source for military operations. When paired with targeted technology development and thoughtful integration into planning processes, geothermal systems can reduce logistical burdens, improve energy resilience, and enhance mission success in operational environments.