Renewable Energy
Geothermal
Heating is the most common direct use of geothermal Energy. In the rational use of geothermal energy it’s even more applicated the heat pump. The heat pump is a machine that could transfer heat from a corps to another hotter than that raising it’s temperature.
This system allows to have hot water and heating in winter and then to benefit of air conditioned in summer. We propose two common geothermal’s techniques consisting in installation of horizontal and vertical geothermal probes.
• Which parts constitute a geothermal plant for the house ?
The geothermal plant is constituted by geothermal’s probes that penetrate the soil and by an heat’s pump, a low energy-use device that can transfer energy to heating system, air conditioned system and to a store tank to produce hot water.
• Which types of geothermal’s plants exist ?
There are plants that use the heat of the hearth and others that use water’s heat from a water table.
Above all ther are vertical plants where probes or the canalizations go down deeply in the soil and plants where probes are developed horizontally with a deepness of 60 cm .
• How much space is required to use geothermal’s energy for the house ? What have I to think about ?
About an horizontal plant it’s necessary to use some tens of square metres (an average of 3 m2 for each Kw of energy). In a vertical plant probes go down with a deepness of 100 m but they can reach 150-200m; in this case it’s necessary o investigate on ties of perforability on the soil. In the case of a water table it’s necessary that this is not under water right.
• What about the costs of the plant ?
The costs o fan horizontal plant are really inferior. For an house of 100 m2 in example, it’s necessary to have 200 m2 of probes. Excavations cost about 8 euros for each m2, adding the cost of heat pump the plant costs from 2000 to 2500 euros. Regarding vertical systems probes alone cost about 7000-8000 euros.
• Which are the other benefits o fan horizontal plant ?
They can use also the thermal energy of atmospherical agents like wind or rain that could be used only on the superficial stratus of the soil.
• What is the cost of maintenance ?
The cost of maintenance is about the 20% of a traditional boiler plant
.
• What type of maintenance is needed ?
Probes live 25 years and they don’t require maintenance.
• Are all types of soils suitable to install geothermal plants ?
No, gravelly and sandy soils are not suitable because they are very dry. Generally soils with an high conductivity of heat are suitable for this.
• Which plants are linkabled with geothermal systems ?
Geothermal systems require radiant’s panels on the floor and above all a good thermal isolation. In a bad isolated house, the geothermal plant loses its effectiveness .