Italy is a country with a high geothermal vocation with the presence of numerous fruiting areas both for the production of electricity and for direct uses, such as air conditioning of the environment, thermalism, agricultural uses, industrial processes, etc.
In particular, the use of geothermal heat pumps allows the exploitation of low temperature resources (<30 ° C) even at small depths, present practically everywhere in Italy and in almost all types of soil.
Despite the great potential, the use of geothermal energy in Italy has seen a very modest growth, unlike other European countries (Switzerland, Sweden, Austria and Germany) where it is an already consolidated reality.
Nevertheless, the Italian Geothermal Union estimates within 2030 an interesting growth in the use of geothermal energy, especially aimed at air conditioning of the rooms through heat pumps.
"For the specific contribution of the different sectors of direct uses"
- reads in the UGI document - "
an important increase in absolute value is estimated for everyone; but the air-conditioning of rooms, already in first place in the 2010 will become more important until it is in 2030 over 60% of the total ".
Low enthalpy geothermal and heat pumps
When we talk about domestic or “low enthalpy” geothermal systems, we refer to systems that use low temperature geothermal energy for air conditioning through heat pumps. The fundamental elements of a geothermal plant are:
1. Heat collection system
These are buried plastic pipes that act as heat exchangers, exploiting the thermal energy present in the subsoil or in the water
2. The geothermal heat pump
Installed inside buildings, the geothermal heat pump is the heart of the system. It does not require deep perforations and allows energy to be extracted from the ground (or ground water) to provide heating to the indoor environment and to reverse the cycle ensuring cooling in summer.
For non-high cooling needs and in the mid-seasons the heat pump can be bypassed, using only the difference in ground temperature to obtain the comfort conditions required in the environment: the so-called free-cooling allows to obtain cooling with the contribution of much less energy than would be required by a traditional system.
3. Heat distribution system in the environment
The best solution in combination with heat pumps are the radiant panels: in winter they circulate hot water to 30-35 ° C and in summer cold water to 18-20 ° C, heating and cooling with the maximum degree of comfort and savings energy.
Advantages of a geothermal system
Choosing a geothermal system means obtaining heating and cooling with a single system, using environmentally friendly technology that is economically advantageous.
The main advantages of a geothermal system are:
- Possibility of exploiting an inexhaustible source of energy at almost constant temperature conditions;
- Complete autonomy of the structure from the energetic point of view, for what concerns the summer and winter environmental air conditioning;
- Integration with other renewable sources, in particular, solar thermal, photovoltaic and biomass
- Possibility of free air conditioning in summer and in the middle seasons through "free cooling";
- Drastic reduction of the so-called "indoor pollution" (ie developed in internal environments) thanks to the absence of fumes or dangerous residues of unburnt gases, also eliminating the risks of explosion resulting from losses from gas distribution pipes or underground tanks of LPG or diesel.
- Elimination of the costs of the gas system, including ancillary costs for the connections and the flue.
- Maximum adaptability to many applications, from civil homes, to commercial buildings, hotels, schools, swimming pools, business centers, craft areas, etc.
- The internal installation of the heat pump without the presence of external units allows its use even in areas where there are architectural or aesthetic constraints
- Absolute noiselessness of the heat pump
Legislative simplification and incentives
Also in the government sector, interest in the development of technologies that exploit geothermal energy is growing.
The Legislative Decree 22 / 2010 has simplified the rules for obtaining authorizations both for projects for the exploitation of geothermal resources for energy purposes, and for applications for air conditioning of buildings, greenhouses and sports facilities through geothermal heat pumps.
An opportunity that is worth taking is the Ecobonus 2018, which allows you to bring in tax deduction up to 65% of expenses to improve energy efficiency and housing performance; for condominiums there is an increase in deduction up to 75% up to the whole 2021.
Furthermore, even with geothermal heat pumps, the Thermal Account incentive can be used.