Techno-economics of Enhanced Geothermal Systems Across the United States Using Novel Temperature-at-Depth Maps

Abstract

As geothermal technology continues to gain momentum, it becomes increasingly important for stakeholders to assess the economic feasibility of geothermal power projects when integrated into electricity markets. This study developed geographical maps demonstrating the techno-economic viability of enhanced geothermal systems (EGS) across the continental United States. Particularly, we modeled the design and operations of the upstream, midstream, and downstream system components to evaluate the levelized cost of energy (LCOE) of various EGS targets. This study integrated accurate techno-economic data including geothermal resource characteristics, capital and operational costs, temperature-at-depth maps, weather patterns, proximity to transmission lines, amongst others. Given its crucial impact on the viability of geothermal resources, we particularly developed new temperature-at-depth maps for this purpose. We also used an open-source software called Flexible Geothermal Economics Modeling (FGEM) from our previous work, to capture the effect of hourly weather variations on geothermal operations. Evaluating LCOE of EGS across depths of 1-7 km, we found that there were many sites across the continental United States where LCOE improves continuously with depth due to the favorable geothermal gradients despite the increase in drilling costs. We also found various location across depths with LCOE of less than 50 USD/MWh, which would be profitable under today’s power market pricing.