Thermal heating of the house. Cons of geothermal heating Other options for heating systems

The development of technology allows the use of self-regenerating energy sources - wind, water of the earth. Over the past decade, the production of installations that use geothermal energy has increased several times.

For example, in Sweden, more than 70% of new buildings use a heating system that uses the energy of the earth. Another advantage of such a system is that in the summer season it performs the function of a passive air conditioner.

The principle of operation of a geothermal heating system

The heart of a geothermal heating system is the heat pump. Using the Carnot cycle, it converts the low-temperature heat carrier of the geothermal circuit into a heat carrier of the heating system heated to 50 ° C. At the same time, the efficiency during such work is 350-450%. The motor resource of the heat pump before overhaul is 100 thousand hours.

A temperature of 50°C is optimal for maximum efficiency of the heat pump. Therefore, it is advisable to use underfloor heating or air heating to heat the house, since radiator heating systems are not well suited for operation in geothermal heating systems.

Ultimately, we get: for 1 kW of electrical energy used, we get about 3.5 kW of heat, which, due to the rise in the cost of heat carriers, is essential for saving our own budget.

Functional features of the system

The geothermal system of a private house consists of three circuits:

• Ground collector - a system of special pipes, with an installed recirculation pump. The temperature of the coolant of the external circuit fluctuates within 3-7°C. A delta of 4°C is enough for a heating system. The heat transfer medium is mainly ethylene glycol or a mixture of ethylene glycol and water.
• The heat pump circuit "takes" heat from the ground collector and transfers it to the heating system of the house. Depending on the area of ​​the house and the required heat output, it can generate up to 3500 kW of heat. The coolant for pumps from different manufacturers are: Thermia and Mammoth - ethylene or propylene glycol, for Heliotherm - Puron gas,.
• The circuit of the heating system, in which the coolant heated to 45-50 ° C enters the heating system.

Constructions of geothermal heating systems

When installing a geothermal system, the differences mainly concern only the external ground collector. There are four main outline layouts:

• Horizontal - the soil collector is placed below the depth of soil freezing (from one to one and a half meters - for different regions of the country). The following pipes are used as external collector pipes: metal-plastic, copper in a PVC sheath. The heat transfer of the earth is 10-25 W / m 2 and up to 50 W / m 2 for soil with a high level of groundwater. To obtain 7-9 kW of thermal energy, the collector area will be 300-500 m 2, depending on the installation conditions. With such a laying of the collector, it is not allowed to dig trenches near trees closer than 1.5 m. It is necessary to carry out landscaping and landscaping after the installation of the system is completed.

• Vertical placement - several wells are drilled for installation, in different directions and at different angles. Geothermal probes are laid in wells. In this case, the heat transfer is about 50 W/mp. Thus, to obtain the same 7-9 kW of thermal energy, 150-200 meters of wells are needed. At the same time, the landscape design of the site will not be affected, you need very little space to install the caisson and place the prefabricated collector in it.

• Water-placed circuit - an external heat exchanger is mounted in a nearby reservoir at a depth of 2-3 meters. One of the main requirements for such an arrangement of the heat exchanger is the proximity of the house to the reservoir up to 100 m, and the surface area of ​​the reservoir should be at least 200 m 2.

• Air heat exchanger - the external circuit takes heat from the air. They are effectively installed in the southern regions of the country. The main advantage of such a scheme is the absence of any earthworks, and the disadvantage of such an arrangement of equipment is the drop in plant efficiency to 100% at an air temperature of -15°C. And completely incapable of working at a temperature of -20 ° C.

Benefits of a geothermal heating system

Let's look at the main advantages of such a heating system:

• high efficiency - 350-400%;
• stable thermal characteristics of the heat pump;
• small installation volume;
• service lines for geosondes is up to 100 years, for a heat pump - up to 30 years;
• the ability to provide air conditioning;
• independence from energy carriers;
• maximum autonomy.

Prospects for the development of geothermal systems

Heating systems of geothermal type have low popularity due to their cost. So, for a house, about 200 m 2, a turnkey geothermal heating system costs about one million rubles, the lion's share - 30%, a heat pump.

In the Baltic States and Western Europe, when a house owner installs a system on self-regenerating heat sources, then the state compensates part of the costs of installing this system. At the same time, the payback period for a geothermal heating system is up to 5 years. Since the system is fully automated and does not require human intervention, the level of comfort is much higher than with heating with other types of fuel. The choice is yours.

The development of any civilization is associated with the satisfaction of the requirements for one's home. Wherever a person lived in a cave or a modern skyscraper, caring for warmth and comfort was as important as getting food. Warming himself with a small fire, a stove or a modern heating system, he was forced to use firewood, coal, peat, diesel fuel, burning the priceless gifts of nature.

Technological development has made it possible to build powerful hydroelectric power plants, learn how to use wind energy, and, having comprehended the secrets of the inner layers of the earth, to think about creating an alternative method of using accumulated heat in the form of geothermal energy systems.

At the heart of the solution of the principle action of a geothermal heating system are the laws of physics discovered by scientists. The search for materials that can change their properties, while releasing a certain amount of heat, made it possible to create not only ordinary refrigeration units, air conditioners, but also powerful

It is with their help that it is possible to transfer the heat that always exists in the bowels of the earth to our house, carrying out the coordinated control of three special circuits that make up the heating system. The purpose of the external circuit is to take thermal energy from the ground or water. The coolant in it is a non-freezing liquid.

This heat is transferred through the heat exchanger to freon, which fills the second circuit of the system. Its physical properties, consisting in a low boiling point, allow energy to be obtained during the transition to a gaseous state. And for this, the temperature coming from the external circuit is quite enough. The third internal circuit of the heating system is the required number of radiators, pipes used in the house. It can be separate or shared with the hot water circuit included in the project.

Functional features of the system

The principle of operation and functional features of the geothermal heating system at home are to perform the following steps:

1. The solution located in the outer circuit acquires additional heating in the ground by about 5 degrees. Its final temperature may be in the region of 3.
2. Having entered the pump heat exchanger, the solution transfers its even small energy to freon, for which it is quite enough for evaporation. Passing into a gaseous state, freon enters the compressor, where it is compressed. The thermodynamic processes that take place in this case lead to a rise in temperature up to 100. And already hot gas is supplied to the heat exchanger, where it transfers energy to the heat carrier of the internal circuit, most often water. Thanks to the scientific work of physicists and engineers, this process has been studied in detail and laid down in the fundamental foundations of the operation of various types of modern equipment.
3. The coolant of the internal circuit reaches a temperature of 50-70 and enters the radiators, pipes. Cooled freon enters the expansion screen, its temperature and pressure drop to their original values ​​and the whole cycle can be repeated again. The solution of the outer circuit in the same way moves into the depths of the earth for a new portion of energy.

Designs and types of geothermal heating systems

The first issue that has to be addressed in the process of creating a highly economical geothermal heating system is the choice of the type of external circuit, which is a heat exchanger located underground or in water. At the same time, it is necessary to take into account not only your desires for the architectural fantasies of a new house, but also detailed geodetic studies of the area in which this house will stand or has already been built.

Not everywhere there are hot springs, geysers, volcanoes, but we are given the opportunity to use the warmth of mother earth almost anywhere on the planet. The main thing is to have a clear understanding of the technical side of the matter and the amount of necessary financial investments in any project to create a geothermal heating system.

The following types of heat exchangers are most widely used:

1. Horizontal heat exchanger. This option can be considered as an effective offer, only if there is a large free area near the house. It can only be used as a simple green lawn. Moreover, with the area of ​​​​the house, for example, 220 sq. m. the heat exchanger will be located on an area of ​​600 sq.m. Pipes are laid in special trenches, the depth of which should be below the level of soil freezing in this area.
2. Vertical heat exchanger. From a space-saving point of view, this option certainly has certain advantages. The problem may be the creation of special wells, the depth of which reaches 200 m, with a diameter of about 150 mm. Earthworks with drilling rigs are not cheap in any region. But the soil at such a depth always has a temperature of about 15, which ensures reliable operation of the system with a vertical heat exchanger.
3. Heat exchanger at the bottom of the reservoir. The most economical and simplest method of creating the outer contour of a geothermal heating system. Especially if you have your own reliable pond or permission to use a public reservoir. The distance to the reservoir from the house should not exceed 100 m, and its depth is 3 m.
4. There is a variant of an open heating system based on the use of water coming from an artesian well. It is driven through the heat pump as a heat carrier. For the reverse discharge of water, it is necessary to build a second artesian well. But such a system is not possible everywhere. At the same time, a very important factor is the return of water in the same amount to the deep layers of the soil to maintain pressure in the reservoirs.

Interestingly, the first attempts to drill wells to use heat were made in the middle of the 18th century, but it was not until 1907 that an Icelandic farmer was able to direct hot steam from a nearby source through a cement pipe to his house.

The next step was also taken in Iceland, and only in 1903 the first 3 km long pipeline appeared in Reykjavik. Currently geothermal heating system is very popular in many European countries, USA, Mexico, Japan, New Zealand.

Advantages and disadvantages

Geothermal energy, the reserves of which are so large that only 1%, hidden in the earth's crust with a total depth of 10 km, can provide a volume 500 times greater than all the world's oil and gas reserves.

There are four main types of geothermal energy:

1. This is the heat of the earth from shallow depths, used by heat pumps.
2. The energy of hot steam, water in the earth's crust, currently used to generate electricity.
3. Heat coming from deep layers without the presence of water and magma energy accumulated in volcanic zones.
4. The use of this amazing gift of nature is determined only by the existing level of technology, the possibilities of technology and economic calculation.

Modern designs of geothermal heating systems have both positive and negative points.

The main negative is the cost. But it only seems at the initial moment. All costs pay off according to various data for 4, 5 years. This is due to the fact that modern models of heat pumps use much less energy for their work than any other heating systems. When consuming 1 kW of electricity, their return is 5 kW.

Positive points:

1. They do not burn fuel and do not produce harmful emissions of various compounds into the environment.
2. Minimum maintenance costs with high efficiency.
3. Environmental Safety.
4. Reliable fire safety properties of the system.

Efficiency and payback

You can not call geothermal energy a free gift of nature. The creation of heating systems based on it can amount to over a million rubles without taking into account the cost of a heat pump. It all depends on the required volumes of heating, its functional purpose and type. Usually, the economic feasibility of geothermal heating systems is calculated by comparing the costs of its maintenance.

The cost of any kind of energy used is not constant and will never decrease. In this regard, the alternative replacement of them with the use of the heat of the inner layers is, of course, economically viable and expedient, since heat pumps do not consume much energy, and it is not necessary to build expensive factories and power plants to extract and process thermal reserves.

Moreover, each generation of scientists finds new solutions for creating equipment and technologies in this direction. In addition, it is more correct to estimate the cost of heating systems equally for all types of fuel from zero without using existing centralized supply systems, for example, gas. And then the payback of the system in 5 years will become a real value.

The use of geothermal heating systems is reminiscent of the question, why not drive a Zaporozhets car at the present time. Of course, you can, especially off-road and into the forest for mushrooms. But you want to be faster and more comfortable. So it is in this case. One idea that your own heating system does not violate the environment, does not interfere with the life of even the smallest and unknown creatures in nature, will confirm the correctness of choosing a geothermal system.

Mounting and installation

It is better to install such a heating system not on your own, but by attracting specialists at least for certain types of work with self-confidence.

The main steps are:

1. Calculation of the internal contour of the heating system. This includes in detail the total length of the pipeline, the number of radiators, the creation of heated floors, the use of heat to produce hot water in the house.
2. Calculation of the laying depth of pipes of the external circuit for the selected type of heat exchanger. It is necessary to take into account the geodetic data of the area.
3. Drilling of the necessary shaft and installation of pipes. In the absence of a centralized water supply at the same time, it is easiest to solve the issue of creating other wells for water. The technology of their creation is different and requires special knowledge.
4. Selection and installation of the required model of the heat pump.
5. Installation of automatic devices monitoring the operation of the entire system and regulating the microclimate in any area of ​​the room.

Overview of pumps: manufacturers and models

The efficient functioning of the entire system is determined by the right choice of heat pump. According to the principles of operation, the pumps belong to the modern environmentally friendly type of equipment. In the process of their work, no harmful substances are released into the environment.

They are divided into:

• compression;
• absorption heat pumps;

The former are powered by electricity, the latter can use the energy of other types of fuel.

Currently, there are a fairly large number of companies on the market for this type of equipment. This allows you to purchase a heat pump for any power through a combination of different models, which is convenient for creating geothermal heating systems on an industrial scale.

The classic option is the use of heat pumps from Waterkotte Germany. This is equipment with a constant efficiency of up to 500%, independent of external factors. Having started production of heat pumps since 1970, the company is constantly updating a wide range of modern models without losing high quality.

The new EcoTouch pump series, which has won numerous awards, confirms this fact. It includes DC 5027 models with output power from 6 to 26 kW and user-friendly intuitive touch controls. The best modern pumps include the Nibe F1245 model (Sweden), Korsa, Russia. The table shows the estimated cost of individual pump models.

Heat pump cost

Name	Heating power, maximum value, kW	Heated area, m 2	Price, rubles
EcoTouch AI 1 Geo	from 7.8 to 13.8	200-400	538 800 – 590 700
EcoTouch DS 5027 AI	5.9 to 7.3	100-200	337 800 – 379 000
F1126	from 5.56	100-200	from 240 000
F1145 PC	3,85	up to 100	316 300 – 397 200
HOTJET H-16w	from 5.53	200-400	291 560

Price overview for geothermal home heating

A complete calculation of the creation of a geothermal heating system can be carried out only on a specific application, taking into account all the requirements. It is correct to choose the nearest company working in this direction, and work out all the little things under the guidance of specialists. An example is the cost of the range of services of the Russian company Geoterm-Comfort.

The cost of the geothermal heating device:

Heated area of ​​the house (sq. m)	Heat pump power (kW)	Heat pump price (rub.)	The sum of all costs for the construction of an earth contour, including drilling wells and connecting a pump (rubles)	Total:
90-110	10,5	250 000	324 000	574 000
140-150	14	260 000	427 000	687 000
170-190	17,5	280 000	476 000	756 000
200-230	21	315 000	529 000	844 000
330-370	35	470 000	850 000	1 320 000

Development prospects

Modern technologies in industry, used to create new equipment, allow almost every owner of their own home to take advantage of the warmth of the deep layers of the earth. The importance of the possibility of reducing the energy costs of maintaining a home will only increase over time. Therefore, the process of development and implementation of geothermal heating systems cannot be stopped even by expensive projects. For, in the final analysis, this is an undoubted gain and also concern for the ecological heritage for the next generations of our planet.

Each owner of a country house faces such an important issue as ensuring the supply of heat to all residential premises. Today, various manufacturers offer their own options for individual heating of private cottages outside the city. A novelty in this area can be called geothermal heating. Of course, most homeowners believe that such a convenient and economical heating system can only be installed in areas where there are geysers, volcanic formations and hot water sources. Modern installations of this type are able to successfully operate in temperate latitudes, with warm springs at low temperatures.

Features of geothermal heating

Geothermal heating refers to alternative types of heat supply in the house. This option of a thermal installation can be called almost ideal for arranging a private house or a country cottage. To work in the system is used geothermal Energy, which is extracted from various natural heat sources. The basic principle of operation in such an installation is similar to the operation of a walking system. The main difference is the following: if in the refrigerator the refrigerator produces cooling for air from the resulting system, then thermal energy. Coordinated work is possible even with low temperature performance.

The main feature of geothermal heating in the house is that during the warm summer season the air in the house is cooled, but in winter it heats up. At the same time, the cost of such heating is very low in comparison with other thermal installations. In some ways, the operation of such a system is similar to air conditioning. It helps to create the necessary warmth and comfort in the house, providing the owners with comfortable living conditions in the house.

The principle of geothermal heating

The geothermal installation operates offline, while clearly regulating the required room temperature. The principle underlying its operation is the same for all installations, so it is independent of various manufacturers of components. The main work is assigned to special pumps, which may have some differences between themselves in terms of design solution, varieties, but at the same time coefficient data in terms of heat performance, they are all similar. In terms of energy used, the geothermal system works successfully with various types of earth energy.

The system consists of two circuits, namely:

• internal;
• external.

The first of those mentioned is represented by a heating installation familiar to many from the connection of pipes and radiator elements. The outer contour is overall heat exchanger, which is mounted under the earth or in the water massif. Inside, a special liquid with the addition of antifreeze circulates through it, sometimes it is also filled with plain water. The coolant is gaining ambient temperature, and already heated goes further to the geothermal pump. The heat accumulated in this way is transferred further to the internal circuit. This allows you to warm up the water in the radiator elements and pipes around the house.

Ways to implement a geothermal installation

Such heating differs among themselves in the ways of installing a heat exchanger. Three varieties are currently in use:

1. Vertical heat exchanger: it is compact and has a higher cost of installation compared to other types. To install a vertical heat exchanger, you do not need to use a large area, but you need to use specialized drilling rigs. Depending on the chosen technology, the depth of the finished well can reach up to 200 meters, the minimum indicator is 50 meters. The service life of the system is up to one hundred years. It is advantageous to install this type of geothermal heating in the case of installation on an already equipped site. The landscape of the area will remain practically untouched.
2. Horizontal heat exchanger: this type is used quite often. When installing a horizontal heat exchanger, the pipes are laid to a large enough depth, which necessarily exceeds ground freezing level. The main disadvantage of using just such a wiring is that a large area must be used for mounting the collector. It is difficult to lay such a system on an already equipped site.
3. water-placed heat exchanger: this installation is the most economical in terms of costs among the whole variety of geothermal heating, as it works due to energy of water masses. Such a system is relevant for those homeowners who have some kind of reservoir at a distance of hundreds of meters. Such a heat exchanger the most profitable which makes its installation the most appropriate among all types of such heating.

Pros and cons of geothermal heating

Geothermal heating became relevant in America during the crisis in the 80s. Initially, the installation of installations cost a lot of money and such heating was used exclusively by wealthy people, but later geothermal heating became more accessible for public use.

Benefits of using geothermal heating in a private home:

• geothermal energy can be obtained and subsequently used almost anywhere;
• the supply of this type of heat is unlimited;
• the use of such energy is considered the most sustainable;
• geothermal energy does not contain any kind of harmful emissions from the combustion of carbon dioxide;
• heating based on a geothermal installation does not require constant maintenance of the house;
• heating is considered free for the owner of the house;
• installation pumps take up much less space than similar thermal installations, a geothermal pump for installation needs about the same amount of space as, for example, a refrigerator;
• geothermal energy helps both to heat the room and, if necessary, to cool it, the principle of operation is similar to the algorithm of air conditioners;
• if desired, such heating can be installed in conjunction with other heat supply systems, for example, with a gas system, diesel or powered by solar energy.

Despite a number of positive aspects of using this type of heating, geothermal installations have their own limitations, the main ones are:

• high cost of installation of the entire system;
• long payback period.

Such shortcomings of the heating system pale in comparison with the current trends in the global rise in the cost of various types of fuel. Of course, the payback period is long, but over a hundred years, a geothermal installation will show all its advantages and prove its economy on practice. This type of heating has already been appreciated in a number of European countries and in America. For example, in Sweden, about 70% of private homeowners have chosen just such a system as heating.

Video

Sergey Elgazin found out everything about geothermal heating in one of the Finnish houses:

There are a number of autonomous engineering systems that are an integral part of any private country house. One of them is the heating system, which provides a comfortable temperature of the internal air of the house for living at any time of the year, in accordance with the weather conditions.

Geothermal heating is a promising option for heating, which is based on the use of natural resources - the heat of the earth, which is an inexhaustible resource. The heat pump transfers the heat from the ground or surface water to the heat carrier circulating through the heating system inside the house.

Hydroinzhstroy will perform all the work necessary for the organization of geothermal heating: we will prepare a project, select and bring equipment, carry out earthworks, carry out installation and commissioning. Everything will be done on time and with the highest possible quality. We give a guarantee for the work performed.

Benefits of geothermal heating

Profitability. High efficiency of work - having spent 1 kilowatt of electricity, a ton emits 3–5 kW of thermal energy. For comparison, in electric heating systems, 1 kW of electrical energy is converted into 0.7-1.0 kW of thermal energy.

Security. The fuel does not use explosive and flammable fuel.

Ecological purity. No gas leaks. The absence of smoke and smell in the premises. No air pollutant emissions.

Comfort. Ease of operation and maintenance. High degree of automation. Possibility of use as an air conditioning system in the summer.

Autonomy. Independent work under the control of automation.

Durability. The service life of the heat pump is 25 years.

Geothermal heating at home: how it works

The geothermal heating system of the house has three closed circuits. Salt solution or antifreeze circulates through the pipes of the external circuit, located in the ground or water, which removes heat. Passing through the heat exchanger (evaporator) in the heat pump installation, it gives off heat to the refrigerant of the internal circuit. The heated refrigerant is pumped by the compressor, as a result of which the temperature of the refrigerant rises. Through another heat exchange device (condenser), the refrigerant transfers its energy to the heating circuit of the house.

The outer loop can be a horizontal collector or a vertical probe.

Horizontal manifold

1. Collector pipes are laid on the horizontal surface of the bottom of a trench dug to a depth of 1.5 meters - below the freezing level of the soil. For laying pipes, a free area of ​​​​a large area is required, on average - about 500 square meters.

2. The collector is laid on the bottom of the reservoir.

Vertical probe

If there is no river, pond, lake nearby, and the area of ​​​​the site is such that it is not possible to mount a horizontal heat collector, you can drill an artesian well and lower a vertical probe into it - a pair of U-shaped HDPE pipes through which brine will flow and collect soil heat. The number and depth of wells are calculated depending on the heated area of ​​​​the house and the hydrogeological conditions of the site.

Disadvantages of geothermal heating

geothermal method of heating a house - significant capital costs will be required.

Volatility - the system requires power to operate. To avoid the interruption of the heat supply to the house due to a power outage, it is necessary to purchase a gasoline or diesel fuel-powered electric generator.

Soil hypothermia occurs in the area where the heat collector is located (usually due to design errors). Leads to violations in the work of the system.

The cost of geothermal heating

The organization of heating based on a geothermal heat pump will require considerable financial costs. But in this case, the high cost can only be attributed to the shortcomings with a stretch. An efficient, environmentally friendly and economical system is well worth the high initial investment (which will pay off over time). The cost of the system depends on many factors: the area of ​​the heated premises, the power of the heat pump, the installation option for the collector, etc. 000 to 850,000 rubles.

Other options for heating systems

To date, there are many different heating systems, but the heating system using a liquid heat carrier has become the most widely used. Compared to other systems, it has the highest efficiency, practicality and safety. The principle of its operation is that the heat generator (boiler) heats water or non-freezing liquid (antifreeze), which enters the heating devices (radiators, convectors) through pipes, heating them, which in turn heat the air in the room, and returns to the place of its heating.

According to the type of energy carrier, heat generators are divided into 4 groups:

Gas.
The most common and relatively inexpensive option. Gas heating requires the presence of a main gas pipeline or the installation of gas holders. Advantages: economy and high degree of automation.

Liquid fuel.
Heating with liquid diesel fuel is a more expensive method.

Electrical.
It is convenient, but not cheap, to heat the premises of the dwelling with the help of an electric boiler.

Solid fuel.
With a boiler that runs on wood or other solid combustible materials, there is a lot of trouble: you need to regularly load fuel and clean the combustion chamber from ash.

Content

To provide a private house with heat, units operating on electricity, solid, gas or liquid fuels are traditionally used. In recent decades, solar collectors and the heat of the earth's interior have been used as an alternative source of thermal energy. Heating a house using the heat of the earth is called geothermal home heating.

Geothermal heating of the house due to the energy of the earth

Heating from the ground is in growing demand as the cost of conventional energy carriers is steadily rising, while fossil fuel supplies are declining. Investing in earthen heating of a country cottage is quite profitable, taking into account economic prospects and significant savings on autonomous heat supply during the heating season.

Methods for obtaining natural thermal energy

Geothermal heat pumps differ in the way they extract heat:

1. Installations using the heat of deep groundwater, hot geysers, etc.
2. Systems that include an antifreeze tank installed in the ground at a depth of 75 meters. Heating from the bowels of the earth is provided by the natural heating of the container with antifreeze; as a result, the refrigerant, passing through the heat exchanger, gives off the received heat and returns to the tank.
3. The geothermal circuit is laid along the bottom of the reservoir, which is a natural heat accumulator. In this case, it must be taken into account that the reservoir can completely freeze in winter.

Types of geothermal heat pumps

Heating a house with earth energy requires large-scale installation work, but it is an environmentally friendly way to get practically free thermal energy. To heat the house, you will need insignificant expenses for the electricity necessary for the functioning of the system.

Principles of operation of geothermal heating

Heating from the energy of the earth is successfully used in various climatic zones: the systems are able to work in both southern and northern regions.

A geothermal installation, in the course of its operation, uses such a physical property of certain liquids as the ability to evaporate, which leads to surface cooling. It is this phenomenon that underlies the operation of refrigeration equipment.

The principle of operation of geothermal heating is a cooling process launched in the opposite direction. This is how air conditioners work, capable of not only cooling, but also heating the air in the room.

How a heat pump works

However, air conditioning units have a limited capacity - they cannot function at temperatures below -5°C. And the geothermal system is able to provide heating for the house, regardless of the air temperature on the surface. This is due to the fact that in the environment from which it takes thermal energy, stable temperature conditions are naturally maintained.

Geothermal heating system device

Geothermy (the science of the thermal state of the Earth) made possible the practical application of the thermal energy that the earth's crust receives from the hot magma in the center of the planet.

A specially designed heat pump for home heating is installed on the surface, and a heat exchanger is mounted in the ground or at the bottom of the reservoir. Thermal energy is “pumped out” to the surface and allows heating the coolant in the heating circuit of a house or non-residential facility.

How is the heating process

Geothermal heating of a private house is a cost-effective option. If you use the energy of the earth to heat a house, then for every kilowatt of electricity needed to operate the equipment, there are from 4 to 6 kW of useful thermal energy obtained from the bowels of the planet.

In comparison with the operation of the air conditioner, we will see that during its operation, more than 1 kW of electricity is required to obtain 1 kW of thermal energy. This is due to the inevitable losses in the conversion of one energy into another, and so on.

It is very profitable to heat a residential building using the thermal energy of the earth's interior, but the payback period for equipment and installation costs will take some time.

Using the heat of the earth to heat the house does not require the installation of a traditional boiler to heat the coolant.

In this case, the system consists of three components:

• heating circuit - geothermal source of thermal energy;
• heating circuit inside the house - low-temperature radiator or floor;
• pumping station - a heat pump for pumping heat energy into the heating circuit from the heating circuit in the ground or under water.

The geothermal heating system can also be used for heating greenhouses, ancillary buildings, pool water, garden paths, etc.

Geothermal heating equipment

Geothermal equipment for a deep heating system allows you to accumulate thermal energy extracted from the environment and transfer it to the coolant in the heating circuit.

The list of ground heating equipment includes:

• Evaporator. The device is located at a depth, and it serves to absorb thermal energy located in geothermal waters or soil.
• Capacitor. Allows you to bring the temperature of antifreeze to the value necessary for the functioning of the system.
• Heat pump. Provides circulation of antifreeze in the heating circuit, controls the operation of the geothermal installation.
• Buffer tank - a container for collecting heated antifreeze. Allows you to transfer the thermal energy of the earth's interior to the coolant. The tank through which the coolant passes is equipped with a heat exchanger in the form of a coil. Heated antifreeze moves along it, giving off heat.

Diagram of a heat pump device

System installation

Geothermal heating of a country house at the stage of arrangement requires a solid financial investment. The high total cost of the system is largely due to the large amount of land work associated with the installation of the heating circuit.

Over time, financial costs pay off, since the thermal energy used during the heating season is extracted from the depths of the earth with minimal electricity consumption.

Installation of a horizontal heat exchanger for a geothermal heating system

To ensure the heating of the house with the heat of the earth, it is necessary to install a system:

• the main part should be located underground or at the bottom of the reservoir;
• in the house itself, only fairly compact equipment is installed and a radiator or underfloor heating circuit is laid. The equipment located inside the house allows you to adjust the level of heating of the coolant.

What does geothermal equipment look like in a house?

When designing heating due to the heat of the earth, it is necessary to determine the installation option for the working circuit and the type of collector.

There are two types of collectors:

1. Vertical - plunges into the ground for several tens of meters. To do this, at a short distance from the house, it is required to drill a number of wells. A contour is immersed in the wells (the most reliable option is pipes made of cross-linked polyethylene).

Disadvantages: High financial costs for drilling several wells in the ground with a depth of 50 meters or more.

Benefits : Underground location of pipes at a depth where the ground temperature is stable, ensures high efficiency of the system. In addition, the vertical collector occupies a small area of ​​land.

2. Horizontal. The use of such a collector is allowed in regions with a warm and temperate climate, since the depth of soil freezing should not exceed 1.5 meters.

Disadvantages: The need to use a large area of ​​\u200b\u200bthe site (the main disadvantage). This piece of land after laying the contour cannot be used for a garden or vegetable garden, since the system works with the release of cold during the transportation of the refrigerant, which will cause the roots of the plants to freeze.

Benefits: Cheaper land work that you can even do on your own.

Horizontal and vertical collector type

Geothermal energy can be produced by laying a horizontal geothermal circuit at the bottom of a non-freezing reservoir. However, this is difficult to implement in practice: the reservoir may be located outside the private area, and then the installation of the heat exchanger will need to be coordinated. The distance from the heated object to the reservoir should be no more than 100 meters.

Important! The ambient temperature of the collector must not fall below +5°C. The upper part of the collector in contact with the freezing ground must be protected with thermal insulation to avoid heat loss.

Advantages and disadvantages

Heating with earth energy has a number of advantages:

• Efficiency. Compared to the cost of electricity for the operation of a heat pump, the system allows you to get several times more heat energy.
• Environmental friendliness. This type of heating is environmentally completely harmless, there are no emissions into the atmosphere.
• Security. There is no need to use any fuel, chemicals, etc., there is no danger of explosion or fire of the equipment.
• Minimum need for technical support. A properly installed system is able to work without any intervention for at least 30 years.
• Profitability. During operation, there are no repair costs, which allows you to pay back the installation of heating within 5-8 years.
• No need to control the operation of the system.
• Low noise level during equipment operation.
• Inexhaustible source of thermal energy, it is not required to purchase and store an energy carrier.

Environmental friendliness of the use of thermal energy of the subsoil

The disadvantages include:

• initially high equipment costs;
• the need to conduct complex drilling work in the area for the installation of a vertical circuit or spoil the landscape by preparing trenches for a horizontal heat exchanger.

In temperate climates, geothermal installations have proven their effectiveness. In the northern regions, this type of heating is suitable for small houses (up to 200 m 2).

Having figured out how the system works and what parts it is made of, you can determine the possibility of installing it on your own site. Mostly heating from the earth is equipped at the stage of building a house - in this case, it is easier to carry out earthworks, since the planning of the site and the creation of landscape design are still ahead.