| Abstract |
Closed-loop geothermal systems (CLGSs) use a closed-loop heat exchanger such as U-loop or co-axial systems for subsurface heat extraction. These systems have recently received significant attention and investment, with several companies developing and commercializing this technology. Additionally, access to consolidated, independent, high-quality simulations for early scoping and/or project management purposes has become increasingly useful. However, open-source software for rapid data exploration and decision-making for closed-loop projects is limited. Most existing packages or tools serve as general-purpose subsurface simulators, and they may not provide above-ground economic modules. Likewise, their software may operate on legacy code, require local setup, and rely on the user scrpting default conditions or researching hundreds of parameters to roughly mimic a closed-loop system. Furthermore, proprietary applications that comprehensively serve both below-ground and above-ground techno-economics currently need to be purchased. To this end, we present GeoCLUSTER v2.0: an open-source, cloud-native, techno-economic web simulator that enables start-up developers and venture capitalists to rapidly explore the economic viability of closed-loop geothermal systems, such as capital and levelized costs. Users can explore scenarios through several methods: 1) toggling between the heat-exchanger designs, working fluids, and end-use, 2) optimizing power output and economic competitiveness by clicking on the scenario buttons and moving easy-to-use sliders, and 3) visualizing simultaneous graphics and summaries. In GeoCLUSTER’s v2.0 release, we integrate a Slender-Body Theory (SBT) model that enables users to rapidly and semi-analytically simulate any type of U-loop and co-axial system which were not originally included in its first release, such as depths deeper than 5 km and geothermal gradients larger than 70°C/km. This speed and parameter space expansion is due to the SBT’s 1D discretization along the wellbore that, unlike 3D finite element (FEM) or finite volume methods (FVM) that must solve the entire reservoir volume extending outwards from the well, can cut down on orders of magnitude and mesh size. In turn, with data and compute increasingly integrating into the tool, we profile the application’s memory usage and significantly reduce its memory footprint (97% drop). Thus, GeoCLUSTER acts as an agile software for quickly adapting to emergent geothermal feasibility research, and in this paper, we present GeoCLUSTER’s most recent updates as it supports continued systematic evaluation of the technical performance and cost-competitiveness of closed-loop geothermal systems. |