The Integration of 3D Modeling and Simulation to Determine the Energy Potential of Low-Temperature Geothermal Systems in the Pisa (Italy) Sedimentary Plain

Abstract

Shallow, low-temperature geothermal resources can significantly reduce the environmental impact of heating and cooling. Based on a replicable standard workflow for three-dimensional (3D) geothermal modeling, an approach to the assessment of geothermal energy potential is proposed and applied to the young sedimentary basin of Pisa (north Tuscany, Italy), starting from the development of a geothermal geodatabase, with collated geological, stratigraphic, hydrogeological, geophysical and thermal data. The contents of the spatial database are integrated and processed using software for geological and geothermal modeling. The models are calibrated using borehole data. Model outputs are visualized as three-dimensional reconstructions of the subsoil units, their volumes and depths, the hydrogeological framework, and the distribution of subsoil temperatures and geothermal properties. The resulting deep knowledge of subsoil geology would facilitate the deployment of geothermal heat pump technology, site selection for well doublets (for open-loop systems), or vertical heat exchangers (for closed-loop systems). The reconstructed geological-hydrogeological models and the geothermal numerical simulations performed help to define the limits of sustainable utilization of an area's geothermal potential.

Defining the Shallow Geothermal Heat-Exchange Potential for a Lower Fluvial Plain of the Central Apennines: The Metauro Valley (Marche Region, Italy)

“…The adopted methodological approach consisted of the searching of publicly available data related to the main climate, geological and thermophysical features of the lower Metauro sedimentary fluvial plain. As the first 100 m underground is usually affected by thermal exchanges using vertical closed-loop BHEs-e.g., [1,17,18]-we selected this thickness to elaborate the geothermal thematic maps. All the data have been collected and organized at a local scale, corresponding to the investigated area extension.…”

“…The hydrogeological characters of the aquifers represent a fundamental feature to be considered for the evaluation of the heat-exchange potential of the underground arease.g., [17,18,43]. Unfortunately, no recent and complete data have been published on the whole lower Metauro Valley phreatic aquifer, to the best of our knowledge.…”

“…Energies 2021, 14, 768 2 of 18 All these features are necessary to describe the geothermal (or heat-exchange) potential of an area, defined as the thermal power that can be exchanged with the ground through a GSHE with a certain setup [12,13]. For this purpose, the geothermal potential, which is the indicator of the efficiency and suitability for the implementation of a BHE, has been mapped in a great variety of environments and areal scales, with many different techniques, combining climatic, geological, hydrogeological and thermophysical information, usually in GIS environment-e.g., [1][2][3]9,[12][13][14][15][16][17][18].…”

Repurposing Hydrocarbon Wells for Geothermal Use in the UK: The Onshore Fields with the Greatest Potential

“…Use of low-temperature geothermal heat from relatively shallow wells is well established in volcanic regions with high geothermal gradients (e.g., [3,4]). For sites in intraplate regions with moderate heat flow, such as the UK, many workers have identified the combination of social, technical, economic, and regulatory barriers to the adoption of this technology (e.g., [5][6][7]).…”

Active Fault Systems in the Inner Northwest Apennines, Italy: A Reappraisal One Century after the 1920 Mw ~6.5 Fivizzano Earthquake

“…The interior of the SD4 fault-bounded basin is also dissected by a few faults, mainly the west-and east-dipping Cerbaie normal faults, which bound the Montecarlo-Cerbaie horst in the center of the basin. A few other faults (Bientina, S. Croce sull'Arno, and Tinaia) are inferred in the south of the basin from subsurface data [90,93,94,99], possibly connected to the Livorno-Empoli fault. Although the tectonic studies of the SD4 basin faults are still few, the available works show that the cumulative vertical displacement on the Mt.…”