The economic viability of shallow geothermal systems with Borehole Heat Exchangers (BHEs) strongly depends on the thermal load which can be efficiently and sustainably exchanged with the ground. This quantity is usually defined as geothermal potential and, as reported in literature, it mostly depends on the thermal conductivity and the undisturbed temperatures of the ground. The GRETA Project funded by the EU Interreg Program Alpine Space aims to produce maps of the geothermal potential in pilot areas across the Alpine territory to identify the most suitable areas for shallow geothermal installations. This paper presents the case study of the Aosta Valley, where the recently developed G.POT (Geothermal POTential) method was adopted. It describes the data sources used and the assumptions made to derive input parameters (ground thermal properties, usage profile, etc.). In addition, the results of a survey on existing geothermal installations are presented.

The contribution of groundwater to streamflow in Alpine catchments is still poorly understood, despite the fact that it may heavily impact hydrological balance and stream habitats. This paper presents the results of a field campaign based on experiments with heat tracer methods to assess the hyporheic flow during the low‐flow period of a large Alpine river in Italy. These measurements were employed to validate a distributed hydrological model that can be used to asses river–groundwater interaction in both low‐flow and high‐flow conditions. The results show that groundwater may have a relevant role during low‐flow periods, by increasing river discharge and during floods, by subtracting direct run‐off that is stored in river banks. Copyright © 2015 John Wiley & Sons, Ltd.

No abstract

No abstract

I sistemi a pompa di calore che utilizzano la geotermia di bassa profondità (altrimenti nota come a “bassa entalpia”) per il riscaldamento ed il raffrescamento degli edifici rappresentano una tecnologia efficiente e vantaggiosa che può contribuire significativamente alla riduzione delle emissioni di gas serra. Nonostante le bassissime emissioni e i costi energetici significativamente ridotti rispetto all’impiego di combustibili fossili, la diffusione dei sistemi che sfruttano l’energia geotermica a bassa entalpia (profondità generalmente comprese tra i 30 e i 150 m dal piano campagna), è ancora limitata da molteplici fattori. In questo ambito, gli amministratori del territorio esercitano un ruolo chiave in quanto, attraverso la predisposizione di strumenti di vario tipo (informativi, normativi e tecnici), essi possono imprimere un impulso importante allo sviluppo dei sistemi geotermici di bassa profondità, ampliando così il ventaglio di tecnologie attualmente disponibili per lo sfruttamento delle fonti energetiche rinnovabili [...]