geothermal energy
geothermal energy
what geothermal energy is? Geothermal is the heat generated and stored in the Earth. Part of this heat comes from solar radiation. Some other comes from the residual heat generated 4500 million years ago, when the planet was created, which still reaches the surface. The rest of the heat comes from the disintegration of the isotopes present in Earth’s crust and mantle. The geothermal energy for low temperatures is energy that is obtained by extraction of the heat from the Earth. This caught energy is constantly regenerated by effects of the Sun, the rain and the internal heat of the land.
winter
why using geothermal energy?
summer 10º
cold
30º
hot
hot
heat 18º
cold
Geothermal systems use constant Earth’s temperature as heat source during cold periods. Conversely, during hot periods it is used as cooling source. This is possible due to the fact that, few meters under surface, there is a constant temperature circa 10ºC. A standard installation means a 60%-80% saving. The reason is quite simple: transferring excess of heat/cold from the space we want to cool/heat to a space with a constant temperature is easier and cheaper than transferring it outdoors.
heat 18º
advantages • There is no combustion thus Greenhouse gases emissions are considerably reduced. • Hot water, house heating and pools heating requirements are covered in any kind of installation. • It can provide heating, cooling and hot water regardless of environmental temperature, 24 hours/day 365days/year. • The geothermal pump can be installed indoor or outdoor with no exhaust outlet requirement. • It provides a very comfortable heating. It is not dry and temperature constant.
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geothermal energy
How does it work? It uses a heating pump that extracts the heating energy from outside. The energy is extracted at low temperature. It reaches very high temperature due to a compression process performed in a cooling circuit (powered by electricity) thus it can be used for heating or water heating and, if the cooling circuit is inverted, it can also work as a cooling system. Heat pump’s structure is simple and consist on: compressor, evaporator, condenser and expansion system. In a close circuit a coolant liquid flows. This collects the heat from the terrain which the condenser afterwards distributes to the heating and the hot water system. This process takes place in the close circuit of the geothermal heat pump. There, the coolant liquid constantly evaporates, afterwards it is compressed and finally condensed again. This way it is possible to raise the calorific energy from low temperature levels to higher or, contrary, to invert the process (cooling purposes).
field research Thermal Response Research (TRR) is a test performed during first drilling. The ground must be physically and thermally stabilized before starting the test. Its purpose is to determine the characteristics of the ground such as thermal conductivity and volumetric thermal capacity in order to calculate installation’s thermal performance. Based on the data obtained, the exchanger’s installation can be redesigned, optimizing its size by enlarging or reducing it (less number or less deep drillings) in order to ensure a correct energy supply.
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geothermal energy
uses • Houses, residentials, hotels installations.
• Wineries, office climatization, deposit cooling.
• Direct heat comsumption.
• Greenhouses, farms, fish farms.
• Swimming Pools’ conditioning.
• Absorption-based cooling.
• Industrial processes.
• Electricity generation.
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• Heated floors.