Re-Energizing Legacy Fossil Infrastructure: Evaluating Geothermal Power in Tribal Lands and HUBZones

Geothermal energy is a sustainable resource, specifically referenced as a key energy resource in the Trump adminstration’s Declaring a National Energy Emergency Executive Order in 2025, that harnesses heat from the Earth’s crust to provide continuous clean energy. Identifying suitable geothermal sites involves evaluating various geological and geographical factors to ensure optimal resource extraction and minimal environmental impact. This study evaluates potential geothermal sites in South and Southwestern US states with a high concentration of abandoned fossil fuel infrastructure, tribal lands, HUBZones, or all three in order to evaluate how to balance resource development, tribal land rights, and environmental justice in future geothermal energy systems. First, we used publicly available Geographic Information System (GIS) datasets to identify areas that are tribal lands, HUBZones, and/or have orphaned fossil fuel infrastructure. Then, we leveraged geothermal potential GIS datasets to classify subsurface temperatures and calculated how much energy enhanced geothermal system (EGS) technology could produce in these areas using methods from the geothermal literature. The analysis identified promising geothermal sites that overlap with tribal lands, HUBZones, and existing fossil fuel infrastructure in the following states: Arizona, New Mexico, Texas, Louisiana, Mississippi, Nevada, Arkansas, and Oklahoma. These states have at least a technical potential of over 2300 GW and have over 18,000 abandoned oil wells that could be converted into geothermal plants. This potential could contribute significantly to the nation’s renewable energy portfolio while simultaneously providing additional revenue opportunities and environmental remediation to tribal lands and low-income communities by leveraging policies and programs like the Indian Energy Purchase Preference (IEPP) and the Historically Underutilized Business Zone program (HUBZone), respectively.