Geothermal energy is obtained by taking advantage of the natural heat inside the earth to feed heating, cooling and hot water installations in homes. Because it is economical and friendly to the environment, some experts say that it is the renewable energy of the 21st century.
Even the College of Geologists in Spain has asked the government to promote this type of energy for residential uses, hospitals or offices. Many other countries in Europe have already implemented it with successful results.
And although it is not sufficiently recognized, in recent years more people have become aware of its advantages, since on average it achieves savings of more than 70% of consumption. The equipment has a long service life and practically does not require maintenance because there is no combustion, they are also not noisy and do not emit odors.
In Spain there is no official record of thermal renewable energies, however, the director of the company Girod Geotermia, Miguel Madero, estimated that by October 2016 there were about 2,000, according to an article published in "El País".
Unfortunately the ignorance of the population and the presumption that it is a system of highly elevated costs, has played against so that this type of renewable energy has more followers.
Madero exposes a personal experience; explaining that, as the owner of a chalet that has the first geothermal installation underground, it saves around 3,000 euros a year, which would be spent if it used a gas boiler and a conventional air conditioning.
According to "El Pais" sources, more than 90% of the equipment of this type has been installed in single-family homes and the rest in cooperative buildings. Last year, the largest geothermal installation in Spain was inaugurated in the cooperative EAI 310, which plans to amortize the installation, with 70 collectors, in a period of 7 to 9 years, according to the explanation of the architects who coordinate the project .
Margarita de Gregorio, geothermal director of the Association of Renewable Energy Companies, explained to El País that the mechanism of this system works with buried collectors that extract heat from the land and with a heat pump (located inside the building) who transmits it or transports it to the building or home in winter. On the contrary, in summer the house is cooled by transferring heat to the ground through the same exchange circuit.
The specialists explain that, the larger a house, the greater number of holes will have to be made and the deeper the ground, for which it is also essential to carry out a preliminary study.
There are different types of catchment: vertical wells, horizontal uptake and uptake in groundwater.
Currently, the most common catchment system is that of vertical wells. Although it is more expensive, its application is more practical, since they require much less space and at the same time have a higher performance, because the capture probes go deeper where the temperature of the subsoil is more stable throughout year.
For a detached house with a climate without major changes, often with one or two probes it is possible to heat a house, without the need of support from other heating systems.
Horizontal systems, although cheaper, are not as frequent, because they are more vulnerable to external changes in temperature and have lower performance.
Meanwhile, the phreatic catchments can only be executed in certain areas with constantly renewed water aquifers. Unlike the previous captures that are closed circuits, these are open systems that capture the water in a first well, to release it later in a second well downstream of the first or a certain distance.
Invest for the future:
Madero said in the aforementioned report that the initial investment for geothermal energy continues to represent an obstacle for new users, since the cost is similar to the value of installing solar panels, boiler and air conditioning in the house.
"A geothermal installation (soundings, technical room and underfloor heating) can be between 25,000 and 30,000 euros, depending on many factors," says the company Ecoforest that sells air, water and duct stoves.