Low enthalpy geothermal energy is an interesting alternative to the traditional methods of air conditioning in buildings: it is an alternative for heating / cooling that favors environmental sustainability which is well-suited for urban areas.
Many countries are promoting the installation of alternative heating / cooling systems to cope with the climatic emergency and to reduce the rate of pollution highly populated and industrialised areas.
Among these, the low enthalpy exploitation technologies are the most used within the urban environment.
The possibility of being installed anywhere makes these plants a valid alternative to the traditional air conditioning sources as they allow to reach higher environmental sustainability goals.
Since the applicability of these plants depends essentially on the properties of the soil and groundwater, the study of the spatial distribution of the geological parameters and underground temperatures is pivotal for good energy planning at regional scale.
Low enthalpy geothermal energy exploits the constant temperature of the ground or groundwater through heat pump systems which allow to extract heat from a relatively low temperature source. Although the heat pump needs electricity to extract / dissipate heat in the ground, the ratio between the thermal energy produced and the electricity consumed varies from 3 to 5 times.
In general, geothermal plants can be distinguished between two main types:
open-loop systems, which take ground water and then reintroduce it (or to superficial water)
closed-loop systems, equipped with closed-circuit systems with a heat pump or geothermal probe in contact with the ground, but without exchange of ground water
The potential of a geothermal plant depends on several factors including the initial ground temperature, the thermal properties and the hydrodynamic characteristics of the soil. The combination of these parameters determines the efficiency of a certain geothermal plant and is defined by the geothermal potential. The geothermal potential expresses the thermal power (W) that can be exchanged with the ground, or how much heat can be taken or released per unit of volume.
One of the advantages of this type of technology is the absence of on-site emissions, which makes these systems suitable for air conditioning buildings in urban areas. These systems can also be used to support large thermal / thermoelectric power plants. They are called co-generation plants.
Low-enthalpy geothermal energy in Italy is not applied as in other countries (eg the United States, Germany, Switzerland) due to little dissemination and incentive.
Since in Italy there are many alluvial basins (some very extensive like the Po valley) and the energy / thermal demand in densely populated areas is very high,
a study about the potential of these technologies is mandatory to improve and optimize the installation of these plants.
In the PerFORM WATER 2030 project the focus is set on the quantification of the thermal potential of groundwater in the Metropolitan City area of ‚Äč‚ÄčMilan.
Documents on Geothermal published on the web-site of RSE (Ricerca Sistema Energetico), the research center dedicated to energy supported by the Italian Ministry of Economy and Finance
Documents on Geothermal published on "Rinnovabili in Lombardia", the Lombardy Region's web-portal dedicated to renewable energy (please note: italian language only)
Thematic cartography made available by the Environmental and Territorial Information Service of the Provincia Autonoma di Trento
Back to Science & Technology