<p><b>Abstract</b></p><p>Sedimentary basins are ubiquitous, naturally
porous and permeable, and the geothermal heat in these basins can be extracted
with geologic water or CO<sub>2</sub> and used to generate electricity. Despite
this, the broad potential that these formations may have for electricity
generation is unknown. Here we investigate this potential, which required the
creation of the <u>gen</u>eralizable <u>GEO</u>thermal techno-economic
simulator (genGEO). genGEO is built with only publicly available data and uses
five standalone, but integrated, models that directly simulate all components
of geothermal power plants to estimate electricity generation and cost. As a
result of this structure, genGEO, or a portion of it, can be applied or
extended to study any geothermal power technology. In contrast, the current
techno-economic tools for geothermal power plants rely on characterizations of
unpublished ASPEN results and are thus not generalizable enough to be applied
to sedimentary basin geothermal power plants which use subsurface CO<sub>2</sub>.</p>
<p>In this study, we present genGEO as
open-source software, validate it with industry data, and compare its estimates
to other geothermal techno-economic tools. We then apply genGEO to sedimentary
basin geothermal resources and find that using CO<sub>2</sub> as a subsurface
heat extraction fluid compared to water decreases the cost of geothermal
electricity across most geologic conditions that are representative of
sedimentary basins. Using genGEO results and p50 geologic data, we produce
supply curves for sedimentary basin geothermal power plants in the U.S., which
suggests that there is present-day potential to profitably increase the
capacity of geothermal power by ~10% using water as the subsurface heat
extraction fluid. More capacity is available at lower cost when CO<sub>2</sub>
is used as the subsurface fluid, but realizing this capacity requires
geologically storing between ~2 and ~7 MtCO<sub>2</sub>/MW<sub>e</sub>. But
developing sedimentary basin resources in the short-term using subsurface water
may not eliminate options for CO₂-based power plants in the long-term because the least-cost order of
sedimentary basins is not the same for both CO<sub>2</sub> and water. With
sufficient geologic CO<sub>2</sub> storage, developing sedimentary basins using
CO<sub>2</sub>- and water-based power plants may be able to proceed in
parallel.</p>
Feasibility study of repurposing Trenton–Black River gas fields for geothermal heat extraction, southern New York