Geothermal energy in Sicily could play a key role among renewable resources. Indeed, numerous active volcanic zones (Etna, Aeolian Islands, Pantelleria) or areas with high hydrothermalism (Paternò, Sciacca, Mazara del Vallo, Termini Imerese) make the region very suitable for the exploitation of medium-high enthalpy geothermal resources. Although there are anomalous geothermal gradients with rather high temperatures at shallow depths, there is also a huge low-enthalpy geothermal potential in the shallow subsurface that is not always economically used. The Aeolian Arc is one of the most interesting geo(hydro)thermal site of Southern Italy, which could offer exploitation of geothermal resources from low to medium-high enthalpy. Here, we present a case study from Salina, focusing the attention particularly on the area of Santa Marina Salina. Exploration of the subsurface with assessment of lithological and petrographic/petrophysic characteristics of rocks (e.g. type, structure and texture variability, thermal conductivity, etc.) has been performed. Results provide indications about the maximum possible low-enthalpy geothermal energy potential, which is useful for planning technical solutions characterized by high efficiency. The detailed field survey allowed us to get information on lithological/lithostratigraphic features and hydrogeological conditions of the area, with extension of the thematic cartography to the shallow subsurface (0-150 m of depth). These data have been used to derive the distribution of thermal conductivity of the subsurface at various depths. Application of a theoretical model has led to the definition of the most favorable areas for exploitation of low-temperature resources through vertical closed loop systems by using geothermal probes installed at depths lower than 100 m. Our data become crucial for the correct sizing of lowenthalpy geothermal installations.
|Titolo:||Evaluation of the low-enthalpy geothermal potential in volcanic terrains: a case study from the Island of Salina (Aeolian Islands, Italy)|
VICCARO, MARCO [Membro del Collaboration Group] (Corresponding)
|Data di pubblicazione:||2018|
|Appare nelle tipologie:||4.2 Abstract in Atti di convegno|