Do-it-yourself geothermal heating. Underground geothermal heating of the house with the heat of the earth. How to heat a country house with the help of nature
The limited supply of natural energy resources forces humanity to search for alternative energy sources. Geothermal home heating is a great alternative traditional ways heating. This can be confirmed by factual data on the widespread use of geothermal heating systems in Europe and America as the main sources of heat.
A little history! Geothermal heating systems “expanded” significantly in the late eighties of the last century, mainly in America. At the beginning, the substantial investment in installing such a unit allowed it to be used only by wealthy people, but a few years later this system became accessible to less wealthy Americans, raising the importance of geothermal heating systems in the heating equipment market.
In European countries, just two decades ago, the number of geothermal installations exceeded 12 million, but today one can only guess about the size of the “population” of geothermal installations in private homes.
Why is this happening?
It's very simple! The most accessible and convenient system Gas heating reduces natural fuel reserves at a cost out of your pocket. And burning solid fuel (wood, coal, peat) is not only inconvenient, but is also accompanied by the release of harmful carbon dioxide, loss of soot and resins. And it is also necessary additional room for storing fuel.
Operating principle of the system
Geothermal heating systems have a principle of operation similar to that of a refrigerator (air conditioner). Simply, the refrigerator refrigerator cools the air, and the geothermal heat pump heats the heating system coolant.
The heat (energy) of the Earth is used to heat the room. A heat pump located in a house takes energy from groundwater or the soil itself, converting it into heat. This “heat” is then used to heat the coolant in the home’s heating system itself.
Based on the operating principle heat pump lies the reverse Carnot cycle, developed back in the 19th century.
The “heart” of such a system is the compressor, which “compresses” and “transfers” heat. To do this, it needs an external source of energy - an electrical network.
In a company with compressors, the internal circuit of the heat pump operates: a condenser, an evaporator and a throttle valve.
A heat pump works like this:
- The heat intake manifold is filled with an antifreeze liquid (glycol mixture, a mixture of water and alcohol, or salt water) that will transport “underground” or “underwater” heat to the pump.
- This thermal energy in the evaporator is transferred to the refrigerant with a very low boiling point, causing it to suddenly boil and evaporate (turn into steam).
- A running compressor increases the pressure of this steam, which accordingly leads to an increase in its temperature.
- In the condenser, the refrigerant is cooled, transferring heat to the heating circuit of the house, and condenses.
- Through the throttle valve, the refrigerant flows back into the compressor, and the cycle repeats again...
A heat pump can also be called, in other words, an “inside out” refrigerator. After all, in a refrigerator, the refrigerant is heated by the heat of the products placed in it (the refrigerator), and through a system of tubes it is discharged to the rear wall, heating the air outside the refrigerator.
And in the case of a heat pump, this generated heat heats the coolant in the heating system of the house itself. “Warm floors” are most often and more efficiently used as heating devices in such heating systems.
Notice! In the presence of a high-quality and correctly calculated “heat intake” circuit, with a consumption of 1 kW of electricity, the heat pump is capable of delivering up to 5 kW of thermal energy to the system!
Types of heat exchangers for geothermal heating systems
Horizontal heat exchanger
Horizontal pipes are laid to a depth exceeding the thickness of the soil freezing layer.
This option thermal circuit optimal when available large area personal plot without garden plantings (trees). Laying the circuit pipe is not allowed at a distance of less than 1.5 m from the tree crown.
When heating a house of 250 m2, an area of 600 m2 will be needed to accommodate the heat exchange circuit. But such space is not always available. Especially in densely populated cottage towns.
This factor can be called a disadvantage of this type of heat exchanger.
Vertical heat exchanger
A vertical heat exchanger is a luxury that perhaps not every developer can afford. To “arrange” such a heat exchanger, you will need special drilling equipment.
The heat exchanger circuit is lowered into a well 50-200 m deep. To increase the thermal power, several such wells are used, the pipelines of which are connected through special collector units.
The advantage of organizing such a heat exchanger circuit system is the possibility of working in a developed area - this method will not damage the existing landscape.
Heat exchanger placed in water
This option is the most economical to install - there is no need to carry out excavation work, but it requires the presence of a reservoir with an area of at least 200 m2 at a distance of no more than 100 m from the house. The circuit pipes are laid to a depth greater than the freezing depth (at least 2-3 m) at the bottom.
Advantages and disadvantages of geothermal heating systems
We would like to highlight one of the most significant advantages of geothermal heating systems: environmental safety for your home. After all, the process of normal operation of the heat pump is not accompanied by any harmful emissions into the atmosphere. And the absence of flammable substances in fuel pump if there is proper electrical wiring, it virtually eliminates the threat of fire.
The absence of fuel means the absence of costs for its delivery and storage.
Low electricity consumption with relatively high heat transfer (from 1 kW of electricity to 5 kW of thermal energy) is another important (or the most important) factor determining the choice of a geothermal heating system for a country house.
The autonomy of a geothermal heating system frees you from the need to monitor and maintain it.
Important functional advantage A geothermal heating system is its ability to work like an air conditioner in hot weather. In this mode, the opposite happens: heat from the room warms up the refrigerant, which transfers it to the external heat collector.
The disadvantage of such a system is the complexity of its installation and the correspondingly high cost of both installation work and the equipment itself.
Geothermal heating system is the most expensive to install and purchase equipment.
In this case, you can save money on installing this system yourself, but you need to pay significant attention to calculations and consultations with a “pro.”
Using a bivalent heating circuit
The bivalent system involves the parallel use of two heat sources during peak loads (at low temperatures environment).
In such a system, an additional boiler, for example an electric boiler, is connected in parallel to the heat pump. It is used when it is necessary to use intensive heating mode at low ambient temperatures.
If there are few “frosty” days a year in the region where you live, then the presence of such an “assistant” allows you to save on the power of the heat pump, which significantly affects its cost.
A progressive method of geothermal heating of a house uses the operating principle of using the heat of the earth to heat the room. Since traditional fuels are exhaustible natural resources, then you should worry in advance about the transition to the latest inexhaustible energy sources.
Leaders in the production and operation of systems geothermal heating houses are Scandinavian countries. They popularize this installation option and offer it to regions that have wide potential for its use.
Application of equipment
It is incorrect to believe that heating from the ground can only be used where there are hot water springs, warm geysers and other natural underground heating sources. Latest technologies allow you to successfully operate geothermal heating at home and in temperate latitudes.
Today in our country this type of heating is still classified as an alternative method of generating heat. However, in most cases it is almost ideal for country houses or country houses. Do-it-yourself installed geothermal heating at home can operate in two modes:
- heating in winter;
- cooling during hot weather.
This creates the most favorable atmosphere in the room.
VIDEO: How geothermal heating works
System Operation
A heat pump needs to be installed in the house. It will take energy from the soil or groundwater, giving it to the coolant circulating in the house through the pipes. This operating principle was identified back in the 19th century by the French physicist Sadi Carnot.
The components of the base node are:
The compressor is responsible for “compressing” heat and moving it to consumers. The device itself requires an external power source.
The heat pump operates according to the following algorithm:
- The heat intake collector must contain a liquid inside that has a low freezing point. Often, when making geothermal heating with your own hands, water with a high salt content, alcohol diluted with water, and glycol mixtures are poured inside.
- In the evaporator module, heat is transferred to the refrigerant, which has a low boiling point, at which time it boils and turns into a vapor state.
- The compressor installed in the circuit increases the steam pressure, which results in an increase in the temperature of the substance to 78-80 0 C.
- Once the refrigerant substance enters the condenser, it enters the liquid phase, and at the same time energy is released for the heating circuit.
- The resulting liquid is returned to the compressor through the throttle valve.
Since a heat pump for heating a home operates on the principle of a refrigerator, it is often called a “reverse refrigerator.” In many cases, energy from the ground is used to install underfloor heating.
Correctly carried out calculations and well-executed installation of the heat exchanger can provide a fivefold increase in output power from one kilowatt consumed by the pump.
VIDEO: How a geothermal heat pump works
Heat exchanger installation
The current installation types are the following:
- vertical, when you need to drill several wells;
- horizontal, where trenches are dug below the freezing depth;
- underwater, when laying is carried out along the bottom of the nearest body of water.
Well drilling
For effective use thermal energy of the earth, if the area near the building is small, it is necessary to drill deep wells. A stable positive temperature remains several meters deep in the earth. The use of such geothermal wells provides heat to the heat exchanger circuit. This heat is then transferred to a second internal circuit located in the room.
Often, drilling several wells costs even less than laying them along the bottom of a reservoir. Thanks to this, the process becomes accessible to more people.
The process is carried out with a small-sized drilling rig and a small amount of auxiliary equipment. This practically does not affect the surrounding area. Construction of a well is allowed even in water, but it should not be closer than 2-3 m from a residential building.
The maximum usable depth is up to 200 m, but often efficiency appears from a level of 50 m. At the next stage, the well is equipped. A plastic tube with a diameter of 40 mm is placed inside the cavity. From one to four collector loops are passed into it.
The cavity between the soil and the outer wall of the tube must be filled with heat-conducting material. The heating main is being wired and connected to the heat pump.
Water energy
This option is the most rational in terms of cost, since it does not require the preparation of trenches, foundation pits and other earthworks. But this capability is not available to everyone - the minimum volume of the reservoir is sufficient to heat a house of 100 sq.m. must be at least 200 cubic meters and located no further than 100 meters from the housing construction.
Pipes are laid along the bottom of reservoirs to prevent them from freezing during the peak of frost.
Carrying out calculations
To perform a system calculation, it is necessary to take into account the basic parameters:
- at a depth exceeding middle lane Russia 15-20 m, temperature is maintained at +8-+10 0 C;
- For vertical structures It is customary to take in calculations the resulting power value of 50 W per 1 m height, and more exact values depend on the degree of moisture in the rock, the presence of groundwater, etc.;
- dry rock gives 20-25 W/m;
- moistened clay or sandstone 45-55 W/m;
- hard granite rocks will provide up to 85 W/m;
- availability groundwater gives up to 110 W/m.
Using a Heat Pump
The longevity of the system depends on the characteristics and conditions in which the heat pump operates. In geothermal installations it is capable of operating approximately 1800 hours per year. This is the average value for latitudes without thermal underground springs.
Working principle of a heat pump
The operating principle of the thermal heating system is identical and has nothing to do with the country of origin or brand. Geothermal pumps can vary in design, size, appearance, but the heat production coefficient will always be the same for pumps from different companies and different countries. This is due precisely to the peculiarity of processing natural energy into heat.
The pump should not be used too much, as this process can lead to a significant decrease in the temperature of the soil around the well, and sometimes leads to its freezing.
The consequences of such miscalculations ultimately lead to disastrous consequences - the soil sags unevenly, in some places it goes very deep, resulting in damage to the protective plastic pipes. If the house is located nearby, deformation of the foundation or walls may occur due to geological changes.
Periodically, it is necessary to take measures to “regenerate” the soil, for which additional thermal energy. This can be the energy of a solar collector or heating a probe when a heat pump is used in room cooling mode.
In conclusion, it should be noted that geothermal installation is not yet available to everyone. In some cases, the payback period may last more than 10 years, but in the end, these methods of heating a house in the near future will become not just alternative, but the only possible ones.
Do-it-yourself geothermal heating of a house: diagram, drawing, cost, photo and video instructions
How to make geothermal heating with your own hands. The operating principle of a heat pump. How the energy of earth and water can heat a house without firewood or gas.
Not everyone knows that creating geothermal heating at home does not require specific knowledge or skills. But compared to alternative types of heating, geothermal is not so popular, and the reason for this is extremely simple - large financial costs that will pay off only after eight years. Under such conditions, few want to invest money, and in vain.
DIY geothermal heat pump
In a word, take a closer look at geothermal heating, especially since the cost of electricity and gas is constantly growing and it is unclear which energy source will be cheaper to use in a few years.
Pay attention! This heating method was first used in America during the financial crisis of the eighties. Over time, the new product became popular in Europe. In Sweden, for example, today ¾ of all heat is synthesized through heat pumps.
Construction of geothermal systems
Construction of geothermal systems
Even from the name it is clear that the essence of this type of heating is to use the energy of the earth. According to the principle of operation, it vaguely resembles air conditioners or refrigerators.
The main element is a heat pump connected to two circuits.
- The internal circuit refers to the heating system that is familiar to us; it consists of radiators and piping.
- External is a very large heat exchanger installed underground or in a reservoir. It contains a coolant (and it may be plain water or antifreeze), having accepted the ambient temperature, is supplied to the heat pump, from where the accumulated heat enters the internal circuit. This is how heating appliances in the house heat up.
The main element of the system is the heat pump - a device that takes up no more space than a gas stove. The performance of the heat pump is quite high: for every kilowatt of energy used, it produces up to five kilowatts of heat.
Heat pump operation diagram
Pay attention! A conventional air conditioner, whose operating principle is very similar, produces exactly as much energy as it consumes, that is, one to one.
Of course, geothermal heating is the most labor-intensive and expensive today. Most of the money will have to be spent on excavation work and related equipment, including a heat pump. And many people wonder whether it is possible to save money on this and build, say, a homemade heat pump. To find out, you need to understand the types and features of the equipment.
Pros and cons of the system
Here are the main advantages of this heating method:
- use of the inexhaustible energy of the earth;
- high productivity factor;
- no risk of fire;
- efficiency;
- ease of maintenance and operation;
- no need for fuel storage;
- autonomy;
- environmental friendliness and safety.
The only disadvantages include the high cost of installation, but, as already mentioned, these costs will certainly pay off.
Pay attention! Geothermal heating is most beneficial in tandem with “warm floors”, as well as in houses whose area does not exceed 150 square meters.
Methods for constructing geothermal systems
Methods for constructing geothermal systems
One of essential elements is the thermal circuit. When positioned vertically, it can lie at a depth of 20 m to 150 m, depending on the geological circulation of heat. Horizontal circuits are installed at a depth of up to 2.5 m and are heated due to temperature fluctuations at solar heating or heat loss.
1. Direct heat exchange
Thermal devices with direct heat exchange are in direct contact with the soil. The coolant leaves the device body, moves along an underground copper line, exchanging thermal energy, and returns back.
Such heat exchange is called direct because the liquid is in contact with the ground without any “intermediaries.” Of course, it does not interact with the soil directly, but only exchanges heat with it through the walls of the pipes. Today, such pumps are rarely used; they should not be confused with devices in which heat exchange takes place through intermediate circuits.
Be that as it may, the efficiency of direct heat exchange is quite high, and the financial costs of installation are lower than in most closed systems. The thermal conductivity of copper plays an important role in this, as well as the absence of an electric water pump and an exchanger between the coolant and water, which, as is known, is the main source of heat loss.
It is also worth noting that copper pipelines are expensive, and more coolant is required than for other types of systems.
2. Closed systems
Most of these systems consist of a primary circuit filled with refrigerant and a secondary circuit filled with water and installed underground. To make the secondary circuit, polypropylene pipes are mainly used, and it is filled with water and a small amount of antifreeze.
Water leaves the heat exchanger, moves along the outer circuit, exchanging thermal energy with the soil, and returns. It is characteristic that the outer contour is below the soil freezing level, where the temperature is stable; they also immerse him in the nearest body of water.
Pay attention! Systems submerged in water or located in moist soil are much more productive than dry circuits. Therefore, in dry soil next to the circuit, it is advisable to install a drainage hose that would moisten it.
Closed systems are less efficient than the previous option because they require labor-intensive drilling and long system pipes Also note that closed circuits are installed in two ways - vertically and horizontally.
The vertical circuit consists of two pipes going underground at right angles to a depth of 20-120 m. Their lower parts are connected to each other by a U-shaped connector. Shafts dug for pipes are usually filled with a special solution that improves heat transfer and protects underground aquifers from pollution.
If the system is placed horizontally, the pipes are buried below the freezing level of the soil. Naturally, they run horizontally. For obvious reasons, this method is cheaper than vertical placement (read: drilling), so it is used wherever there is enough space on the site.
3. Horizontal drilling contours
Horizontal Drilling Contours
An alternative to the two previous options may be to lay the contour through horizontal drilling. This makes it possible to install pipes under a garden, yard, road and other objects without destroying them.
In terms of cost, such a system is somewhere between horizontal and vertical installation. Her distinctive feature is that the loops can be connected to only one chamber, and this reduces the area required for installation.
Pay attention! Contours using horizontal drilling are installed after the building is built.
4. Water circuits
Closed circuits that are immersed in reservoirs are a pipeline laid in loops. They can be placed in any lake or pond that is located in close proximity to the house.
5. Open systems
In such systems, the external circuit is filled with natural water. It then moves to a heat exchanger located in the body of the device, where the heat is extracted and transferred to the primary circuit. After this, the water returns back. The supply and return lines must be placed far from each other to efficiently feed the heat source.
Pay attention! All elements of the system must be well protected from corrosion, because... chemical composition circulating water cannot be controlled. This is why it is advisable to use closed circuits if the level of minerals and salts in the water is high.
Despite the fact that the efficiency of open systems is an order of magnitude higher than closed ones, problems may arise during installation, mainly of a legal nature. Installation permits may be required because these systems contaminate wells and deplete aquifers.
6. Columns of liquid
Circuits with liquid columns are one of the types of closed-type systems. In this case, water comes from the bottom of a deep well, passes through a pump and falls back, exchanging heat with the surrounding soil.
Often liquid columns are used where free space is limited. It is not advisable to use this system on clay or sandy soil.
We also note that the structure can consist of several pillars at once and is used mainly in small buildings.
Stage one. Before you start making a pump, it is necessary to take a number of measures to improve the energy efficiency of your home. These measures include insulating floors and walls, replacing leaking doors and windows, and thermal insulation of the roof and ceiling.
Stage two. Then you need to conduct geological exploration to find out the depth of soil freezing. After this, you should draw up a project based on the selected technology.
Stage three. Purchasing everything you need - heating system parts, pipes and a compressor for the pump.
The compressor - the heart of any geothermal pump - should be discussed separately. It is impossible to make it yourself and the only option left is to buy a finished product.
It is better to buy a device with a power of more than 7 kW, used in high-performance air conditioners (such compressors are sold in service centers, specializing in servicing household appliances).
DIY geothermal heat pump
Stage four. Then you can begin assembling the internal heat exchanger. Let us remind you that it is necessary to transfer the accumulated thermal energy to the heating network. The materials for a given element, as well as its volume, completely depend on the specific climatic conditions. For coolant circulation, they are usually used copper tubes, while the container is made of non-corrosion material. Ideally, this capacity should be a 150-liter stainless steel tank.
Stage five. The pre-prepared copper coil must be placed in the tank. This cannot be done without damaging the latter - it must be cut into two parts, and after fixing the coil, welded to its original state.
Stage six. Then you should drill shafts or trenches and install a pipeline there. Upon completion of work, it is necessary to conduct a test run of the system.
Pay attention! Due to the high degree of complexity of the work, it is better to entrust the design and installation of such heating experienced specialists. The same can be said about the manufacture of a heat pump.
DIY geothermal heat pump
Learn how to build your own geothermal heat pump! Geothermal heating system, types of heat pumps, manufacturing stages, photo + video.
Do-it-yourself geothermal heating at home: a comparative review of design methods
Many owners of private houses still believe that geothermal heating is a term almost from the realm of science fiction, and it is relevant only for those regions where hot springs bubble and there is high volcanic activity. And since such natural phenomena are rare, the prospects for using this alternative energy in our conditions look vague for many. In fact, a geothermal pump successfully generates heat even at low temperatures, so even in temperate climates it can be used quite effectively. But is it possible to install geothermal heating at home with your own hands? Let's try to figure this out.
Classification by construction type
The operating principle of geothermal heating is similar to that of an air conditioner or refrigerator. The main element is a heat pump included in two circuits.
Operating principle of a geothermal (heat) pump
The internal circuit is a traditional heating system consisting of pipes and radiators. External - an impressively sized heat exchanger located underground or in the water column. Both a special liquid with antifreeze and ordinary water can circulate inside it. The coolant takes on the temperature of the medium and, “warmed up,” enters the heat pump, the accumulated heat is transferred to the internal circuit. In this way, water is heated in pipes and radiators.
The geothermal (heat) pump is a key element of the system. This is a compact unit that takes up no more space than the one we’re used to. washing machine. If we talk about productivity, then for every 1 kW of electricity consumed, the pump “produces” up to 4-5 kW of thermal energy. While a conventional air conditioner, which has a similar principle of operation, will “respond” to 1 kW of heat for 1 kW of electricity consumed.
Scheme of geothermal heating in a private house
It must be admitted that the installation of this type of heating is the most expensive and labor-intensive to date. The lion's share of its cost is the purchase of equipment and, of course, excavation work. Naturally, a thrifty owner wonders whether it is possible to save money, for example, on installation and make geothermal heating with his own hands? In order to answer this question, it is necessary to understand which systems are used most often and understand the features of their design.
Horizontal heat exchanger
Quite often, a horizontal circuit is used, in which pipes are laid in trenches to a depth greater than the freezing level of the soil in a given area.
The disadvantage of a geothermal heating system with a horizontal circuit is the large area occupied by the collector
The disadvantage is that the area occupied by the circuit must be much larger than the house itself, so to heat a building with an area of 250 m², about 600 m² will go under the pipes. Not every developer can afford such luxury.
In addition, inconveniences arise if the site is already landscaped; for example, you have to observe the distance from trees (1.5 m) and many other nuances.
Vertical heat exchanger
A more compact, but also more expensive option is a vertical heat exchanger. Its installation does not require a large area, but it will require special drilling equipment.
Installation of a vertical heat exchanger requires the use of special drilling equipment
The depth of the well, depending on the technology, can reach 50-200 m, but its service life is up to 100 years. This method is especially relevant when planning geothermal heating of a country house with a developed adjacent territory; it allows you to preserve the landscape almost in its original form.
Water-based heat exchanger
The most economical geothermal installation uses thermal energy from water. It is recommended if the distance to the nearest body of water does not exceed 100 m.
A water-based heat exchanger is the most advantageous and therefore more appropriate for the device
A circuit of pipes in the form of a spiral is laid on the bottom; the depth should be less than 2.5-3 m, that is, deeper than the freezing zone. Reservoir area – from 200 m². The main advantage is that there is no need to perform labor-intensive excavation work, but it is necessary to obtain permission from special services. Having spent significant amounts of money on expensive equipment, you should not save on high-quality installation. After all, the quality and efficiency of the entire system will depend on it.
As you can see, installing geothermal heating at home with your own hands is not so easy. Of all the listed types, perhaps only the last option will be quite easy to implement on your own. But even in this case, it is worth weighing all the pros and cons.
About the advantages and disadvantages of the system
For the first time, geothermal heating was looked at closely in the United States during the crisis in the 80s. Quite expensive installations were installed in the homes of the richest and most advanced, but gradually they became more accessible and popular. Europe took note of the new product and began to actively implement it in its open spaces. Now this type of heating is no longer a curiosity; in Sweden, for example, about 70% of all heat is synthesized using heat pumps.
Manufacturers of miracle equipment and green people unanimously talk about the advantages of this type of heating over all others, the main advantages that are emphasized are:
- Thermal energy of the earth is used for heating, which is renewable and inexhaustible;
- there is no risk of fire;
- there is no need for delivery and storage of fuel materials;
- When the equipment operates, no harmful emissions are generated, the system is absolutely safe and environmentally friendly;
- the system operates autonomously and does not require constant monitoring and intervention;
- it is economical and requires virtually no maintenance costs from the owner;
- With all the variety of models, the equipment productivity coefficient remains consistently high.
The geothermal heating system performed well in combination with “warm floors”. This duo ensures uniform temperature distribution and prevents the formation of overheating zones.
Important! This type of heating is most beneficial for houses with an area of up to 150 m², the owners of such small cottages They claim that the costs are recouped in just 3-4 years.
Note that these systems have not yet become popular in the post-Soviet space. This is largely due to the fairly significant capital investments that will need to be made at the very beginning, and quite long term payback. It is quite difficult to convince our fellow citizens that this is, after all, economically profitable. Although, if we take into account the annual rise in price of conventional coolants and the fact that the system is designed for an average of 100 years of efficient operation, the choice will seem quite justified.
Do-it-yourself geothermal heating of a house - is it possible?
Geothermal heating system - device, principle of operation. Which geothermal heating for a country house to choose. Is it possible to make geothermal heating at home with your own hands?
Do-it-yourself geothermal heating at home
When building a house, each owner tries to think about the weight of the design nuances. Heating no less important point which requires consultation with specialists. For many, geothermal heating seems unattainable, because it is associated only with places where hot springs bubble. However, in practice, a special pump can generate energy, so this option is suitable for any climatic conditions and terrain. However, is it worth doing geothermal heating at home with your own hands, because the equipment itself is already expensive. To find the answer to this question, it is worth studying the existing options and features of installation work.
How Geothermal Heating Works
Geothermal heating works on the same principle as air conditioning. The components are two circuits and a heat pump.
The internal circuit includes pipes and radiators located throughout the house. The external circuit is a heat exchanger, which is placed either underground or under water. Liquid with antifreeze or plain water circulates inside. The heated liquid enters the pump, which accelerates it through the elements of the internal circuit, due to which the water in the radiators is always warm.
The pump does not take up much space, but performs one of the key functions in the system. For every kW of electricity used, it produces 4 times the heat output. The air conditioner is not so productive, because after taking 1 kW of electricity, it gives out the same amount.
Classification depending on the type of structure
This type of heating arrangement in a house is considered one of the most expensive and this is due to the price of equipment and earthworks. At such moments, many consumers wonder what they can save on, and the only thing that comes to mind is installation. However, to understand whether this is so, it is worth evaluating the features of the device and possible options designs.
- Horizontal heat exchanger. When choosing this design, the pipes are laid underground, and the depth should be greater than the freezing level of the soil. However, this option requires the allocation of territory for the contour. Just imagine, if you need to heat a house with an area of 250 m2, then you will need 600 m2 to arrange the circuit. In addition, it is necessary to take into account some technical points. For example, all elements should be located at a minimum distance from the tree - 1.5 meters. If the site is landscaped, then this already creates certain inconveniences.
- The vertical option does not require the allocation of a large area, however, the use of drilling equipment will incur significant costs. Creating a well is a labor-intensive process, however, this structure will last for at least a hundred years. This option is suitable for areas that are already developed.
- The water-based option uses the energy of water and allows you to significantly save on arrangement. The only requirement is the presence of a reservoir within 100 meters, its area must be at least 200 m2, and the structure must be located no deeper than three meters.
As practice shows, it is difficult to carry out installation with your own hands. Considering that there will be a lot of money invested in equipment, you should not skimp on the installation process and should turn to professionals.
Benefits of Geothermal Heating
Previously, such installations could be found in luxurious and wealthy homes, but now they have become more affordable. They were first used by residents of the United States in the 80s, and now residents European countries took note. This solution allowed us to save on heating costs overall. Twenty years ago, 12 million European citizens took advantage of a similar design, but today their number has increased dramatically.
In Sweden already most heat is produced using heat pumps. Accordingly, their popularity has increased due to a number of advantages over all alternative systems:
- The inexhaustible and renewable energy of the earth is used to heat your own home;
- There is no risk of fire;
- You don’t have to look for cheap fuel and think about where to store it;
- An environmentally friendly system, without the formation of harmful emissions, due to which it is actively supported by environmentalists;
- Lack of regular monitoring and intervention; the system operates autonomously at all levels;
- Unlimited amount of energy available at any time and in any quantity;
- You don’t have to spend money on system maintenance;
- High performance compared to existing alternatives.
Experts recommend combining the installation of a geothermal system and heated floors to achieve maximum effect benefits. Firstly, uniform temperature distribution is guaranteed, and secondly, the formation of overheating zones will be avoided.
In order for the costs to pay off in full in 3-4 years, it is worth considering that this type of heating is beneficial to owners of cottages up to 150 m2. Taking into account the fact that conventional heating networks regularly become more expensive and fail, a decision towards a geothermal system will allow you to forget about heat supply for at least 100 years. The chosen option will quickly justify itself. In the post-Soviet space, this option is less popular due to the large investment. It is still difficult to convince our fellow citizens that it is better to spend money once and forget about the problem.
Installation features
If gas and electricity are constantly becoming more expensive, and with them the heating of a private home, then when choosing a geothermal system you can forget about this feature. In addition, you do not have to take into account that gas reserves will exhaust themselves over time. The use of solid fuel is an even more expensive solution. When burning wood and coal, harmful substances are released. Among all the alternatives, this option is the safest, however, unlike gas heating and solid fuel, installation of the system is more labor-intensive and expensive. Therefore, it should be entrusted to professionals with extensive experience in this field. Only they know all the nuances of installation. If the work is carried out correctly, the heating issue will be resolved for many years.
At the same time, inside the room there will be the same pipes and radiators through which heat will flow. The main elements will be hidden underground - a well and a heat exchanger. The house must have a device that will convert heat. It is for this that it is necessary to allocate as much space as possible. With its help, the owner of the premises can regulate the temperature and supply of thermal energy. As a rule, in private homes the generator is located in the basement or a separate room.
Do-it-yourself geothermal heating of a house: diagram and installation features
Features of the selection and installation of geothermal heating. Do-it-yourself installation of pumps and additional equipment in the house.
Ecology of consumption. Estate: We know that geothermy is the heat of the Earth, and the concept “geothermal” is often associated with volcanoes and geysers. Many are sure that do-it-yourself geothermal heating at home is fantastic. But that's not true!
We know that geothermy is the heat of the Earth, and the concept “geothermal” is often associated with volcanoes and geysers. In Russia geothermal energy used mainly on an industrial scale, for example, there are Far Eastern power plants that operate on the basis of the Earth's heat. Many are sure that do-it-yourself geothermal heating at home is fantastic. But that's not true!
A few historical facts
When the oil crisis broke out in the 70s of the last century, a burning need arose in the West for alternative sources energy. It was at this time that the first geothermal heating systems began to be created. Today they are widespread in the United States, Canada and Western European countries.
When we mention geothermal energy sources, we always imagine a valley of geysers or volcanoes, but the sources we need are much closer. And they will help us stay warm in winter and cool in summer.
For example, in Sweden they actively use water from the Baltic Sea, the temperature of which is + 4 degrees. In Germany, the introduction of geothermal heating systems is even sponsored by state level. In Russia there are Pauzhetskaya, Verkhne-Mutnovskaya, Okeanskaya and other geothermal power plants. But there is very little evidence of the use of Earth's energy in our private sector.
Real advantages and disadvantages
If geothermal heating in the private sector has received relatively little distribution in Russia, does this mean that the idea is not worth the cost of its implementation? Maybe it’s not worth pursuing this issue? It turned out that this was not the case.
Using a geothermal heating system for your home is a profitable solution. And there are several reasons for this. These include the quick installation of equipment that can operate for a long time without any interruptions. If you use high-quality antifreeze, rather than water, in the heating system, it will not freeze and its wear will be minimal.
We list other advantages of this type of heating.
- The fuel combustion procedure is eliminated. We create an absolutely fireproof system, which, during its operation, cannot cause any damage to housing. In addition, a number of other issues related to the presence of fuel are eliminated: now there is no need to look for a place to store it, deal with its preparation or delivery.
- Acoustic comfort. The heat pump operates almost silently.
- Significant economic benefit. During the operation of the system, no additional investments will be required. Annual heating is provided by the forces of nature, which we do not buy. Of course, when operating a heat pump, electrical energy is consumed, but the amount of energy produced significantly exceeds the amount of energy consumed.
- Environmental factor. Geothermal heating of a private country house is an environmentally friendly solution. The absence of a combustion process eliminates the release of combustion products into the atmosphere. If many people realize this, and such a heat supply system becomes widespread, the negative impact of people on nature will decrease many times over.
- Compactness of the system. You do not have to organize a separate boiler room in your home. All that is needed is a heat pump, which can be placed, for example, in the basement. The most voluminous contour of the system will be located underground or underwater; you will not see it on the surface of your site.
- Multifunctionality. The system can work both for heating in the cold season and for cooling during the summer heat. That is, in fact, it will replace not only your heater, but also your air conditioner.
Choosing a geothermal heating system is cost-effective, despite the fact that you will have to spend money on the purchase and installation of equipment. By the way, as a disadvantage of the system, they mention precisely the costs that will have to be incurred to install the system and prepare it for operation. You will need to buy the pump itself and some materials, and carry out installation work on the external and internal circuits of the collector.
It’s no secret that resources become more expensive year by year, so autonomous system heating system, which can pay for itself within several years, will always be economically beneficial for its owner
However, these costs pay off in just the first few years of operation. Subsequent use of the collector allows you to save significant money. In addition, the installation process itself is not so complicated that it requires inviting third-party specialists to perform it. If you don’t do drilling, then you can do everything else yourself.
Geothermal heating sources
The following sources of terrestrial thermal energy can be used for geothermal heating:
- high temperature;
- low temperature.
High-temperature ones include, for example, thermal springs. They can be used, but their scope is limited by the actual location of such sources. While in Iceland this type of energy is actively used, in Russia thermal waters are located far from populated areas. They are concentrated as much as possible in Kamchatka, where underground water is used as a coolant and supplied to hot water systems.
To effectively use the earth's thermal energy, you do not need a volcano. It is enough to use those resources that are located just 200 meters from the earth’s surface
But we have all the necessary prerequisites for the use of low-temperature sources. The surrounding air masses, earth or water are suitable for this purpose. A heat pump is used to extract the required energy. With its help, the procedure is carried out to convert the ambient temperature into thermal energy not only for heating, but also for hot water supply to a private household.
Operating principle of alternative heating
If you are familiar with how an air conditioner or refrigerator works, then the similarity of these processes with the principle of operation of geothermal heating is obvious. The basis of the system is a heat pump, which is connected to two circuits - external and internal.
To organize a traditional heating system in any house, it is necessary to install pipes for transporting coolant and radiators, when heated, heat will flow into the premises. In our case, pipes and radiators are also needed. They form the internal contour of the system. Warm floors can be added to the scheme.
The external contour looks much larger than the internal one, although its dimensions can only be assessed during planning and installation. During operation, it is invisible because it is underground or underwater. Plain water or ethylene glycol-based antifreeze circulates inside this circuit, which is much preferable.
The geothermal heating system includes two circuits - internal and external, as well as the heart of the heating system - a heat pump, which, by compressing the coolant, increases its temperature
The coolant in the external circuit is heated to the state of the medium in which it is immersed, and is sent in a “heated” form to the heat pump. Through it, concentrated heat is transferred to the internal circuit, resulting in water in pipes, radiators and warm floors warms up.
Thus, the key element that animates the entire system is the heat pump. If your home has an ordinary washing machine, then know: this pump will occupy approximately the same area. To operate, it needs electricity, but, consuming only 1 kW, it produces 4-5 kW of heat. And this is not a miracle, since the source of “additional” energy is known - this is the environment.
Two types of heat exchanger locations
There are two options for heating a private home using low-temperature energy from environmental elements. The basis of the system in all three cases is a geothermal pump. The internal circuit remains unchanged for any heating method, and the main difference is the location of the external circuit.
Geothermal heating comes with a heat exchanger located:
- vertical;
- horizontally.
Horizontal heat exchangers of the systems are placed in a pit or open reservoir in the form of a kind of coil, vertical ones are located in wells that penetrate or do not penetrate the aquifer.
Each of the types of heating listed here is characterized by its own characteristics, disadvantages and advantages. If you intend to create such a heating system with your own hands, you will be interested in learning more about each type.
Vertical placement of the external collector
This type of heating is based on an interesting natural phenomenon: at a depth of 50-100 meters or more from its surface, the earth has the same and constant temperature of 10-12 degrees all year round.
To be able to use this earth energy, it is necessary to drill vertical wells. In order to preserve the landscape as much as possible, several pipes can be drilled from one starting point, but under different angles. The external circuit of the system will be installed directly in these wells. This will allow you to effectively take away its heat from the earth. Of course, this method can hardly be called simple and low-budget.
To create a vertical geothermal heating system, you need to use equipment for drilling wells; without the use of a drilling rig, solving the problems of constructing the system will be quite labor-intensive
It is relevant in the case when the territory adjacent to the house has already been developed, and disturbing its landscape is impractical. The depth of drilling a well can reach from 50 to 200 meters. The specific parameters of the well depend on the geological situation at the site and the parameters of the future structure. The service life of this design is approximately 100 years.
For the installation of a vertical version of the system with a heat exchanger that extracts energy underground water, it will be necessary to drill two water-bearing wells. From one of them, called the debit one, water is drawn using a pump, which, after heat transfer, is drained into the second, receiving outlet.
The disadvantage of a geothermal system with two wells is that it is not efficient enough to heat a country house. Wastes too much energy circulation pump. But to supply the coolant to the heated floor circuit, the resulting thermal energy is quite sufficient
Horizontal arrangement of the soil collector
To lay the external circuit for horizontal heating, you need to know to what depth the ground freezes in your area. The pipes are laid below the freezing level in pre-prepared trenches, covering a fairly large space: to heat a house with an area of 200-250 square meters. meters, you need to use approximately 600 sq. meters of heat exchanger. That is six hundred square meters.
The disadvantage of this design is the large area it occupies. If you need a lawn covered with grass and flowers on your property, this is your option. It is better to keep collector pipes away from fruit-bearing trees.
It is clear that under such conditions, the volume of excavation work will be significant. In addition, you need to take into account the location of trees and other vegetation on the site in your plan so as not to freeze them. For example, collector pipes should not be located closer than one and a half meters from trees.
This installation method is used, as a rule, in cases where the site is just being developed for construction. All calculations and plans for building a cottage, organizing its heating and planning the land plot are best carried out simultaneously.
Immersion of a horizontal heat exchanger in a reservoir
This method requires a special location of the household - at a distance of about 100 meters from a reservoir of sufficient depth. Besides, specified body of water should not freeze to the very bottom, where the outer contour of the system will be located. And for this, the area of the reservoir cannot be less than 200 square meters. meters.
The obvious advantage of this method is the absence of mandatory labor-intensive excavation work, although you still have to tinker with the underwater location of the collector. And special permission to carry out such work will also be required. However, a geothermal installation using water energy is still the most economical.
Do it yourself: what and how
If you are going to install geothermal heating yourself, then it is better to buy the external circuit ready-made. Of course, we are only considering ways to horizontally position the external heat exchanger: under the surface of the soil or under water. It is much more difficult to install a vertical well collector yourself if you do not have the equipment and drilling skills.
A heat pump is not a very large piece of equipment. It will not take up much space in your home. After all, in size it is comparable, for example, to a conventional solid fuel boiler. Connecting the internal circuit of your home to it is not a difficult task. In fact, everything is done in exactly the same way as when organizing heating using traditional heat sources. The main difficulty is the design of the external circuit.
This arrangement of the house relative to the pond is more common. The main thing is that the reservoir is no further than 100 meters from the cottage
The best option would be to use a reservoir if one is found within a distance of no more than 100 meters. It is necessary that its area exceed 200 square meters, and its depth - 3 meters, which constitute the average freezing parameter. If this body of water does not belong to you, then obtaining permission to use it may become a problem.
If the reservoir is a pond that is on your property, then the matter becomes simpler. The water from the pond can be temporarily pumped out. Then work on its bottom can be done easily: you will need to lay the pipes in a spiral, securing them in this position. Earthworks will only be needed to dig a trench, which will be needed to connect the external circuit to the heat pump.
After all work has been completed, the pond can be filled with water again. In the next hundred years, the external heat exchanger should work properly and not cause trouble to its owner.
If you have at your disposal land plot, on which you just have to build housing and grow a garden, it makes sense to plan a horizontal ground-type heat exchanger. To do this, you should make a preliminary calculation of the area of the future collector, based on the parameters already indicated above: 250-300 square meters of collector per 100 sq. m. meters of heated area of the house.
If you have a plot without buildings or vegetation that you would like to preserve, the soil can simply be removed when constructing an external horizontal soil contour: this is easier than digging trenches
The trenches in which the circuit pipes are to be laid must be dug below the soil freezing level. Better yet, simply remove the soil to the depth of its freezing, lay the pipes, and then return the soil to its place. The work is labor-intensive and complex, but with great desire and determination, you can complete it.
Costs and payback prospects
The costs of equipment and its installation during the construction of geothermal heating depend on the power of the unit and the manufacturer. Everyone chooses a manufacturer based on their own considerations and information about the reputation and reliability of a particular brand. But the power depends on the area of the room to be served.
This figure summarizes the benefits of using a geothermal heating system. It is precisely this ratio of incoming and outgoing energy that allows the system to first quickly pay for itself and then save its owner’s money
If we take power into account, the cost of heat pumps varies in the following ranges:
- for 4-5 kW – 3000-7000 conventional units;
- for 5-10 kW – 4000-8000 conventional units;
- for 10-15 kW – 5000-10000 conventional units.
If we add to this amount the costs that are needed to carry out installation work (20-40%), then we will get an amount that for many will seem absolutely unrealistic. But all these costs will be recouped in a very reasonable time frame. In the future, you will only have to pay minor expenses for the electricity needed to operate the pump. And that's all!
Due to the insufficient efficiency of geothermal systems for heating residential buildings, they are used as an addition to the main heating networks or built in complex with two or more heat exchangers
As practice shows, geothermal heating is especially beneficial for houses with a total heated area of 150 square meters. meters. Within five to eight years, all costs for installing heating systems in these houses are fully recouped.
Video about the principles and results of operation
If you find it easier to perceive visual information, then this video will allow you to see with your own eyes exactly how a geothermal system functions, as well as learn more about who benefits from this type of heating and why.
We invite you to watch a short video in which the owner of a horizontal subsoil collector will talk about his impressions of its operation. Additionally, by watching this video, you will learn about the ongoing costs associated with operating a geothermal heating system.
A progressive method of geothermal heating of a house uses the operating principle of using the heat of the earth to heat the room. Since traditional fuel is an exhaustible natural resource, it is worth worrying in advance about switching to the latest inexhaustible energy sources.
Scandinavian countries are leaders in the production and operation of geothermal heating systems for homes. They popularize this installation option and offer it to regions that have wide potential for its use.
Application of equipment
It is incorrect to believe that heating from the ground can only be used where there are hot water springs, warm geysers and other natural underground heating sources. The latest technologies make it possible to successfully operate geothermal heating at home and in temperate latitudes.
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Today in our country this type of heating is still classified as an alternative method of generating heat. However, in most cases it is almost ideal for country houses or country houses. Do-it-yourself installed geothermal heating at home can operate in two modes:
- heating in winter;
- cooling during hot weather.
This creates the most favorable atmosphere in the room.
VIDEO: How geothermal heating works
System Operation
A heat pump needs to be installed in the house. It will take energy from the soil or groundwater, giving it to the coolant circulating in the house through the pipes. This operating principle was identified back in the 19th century by the French physicist Sadi Carnot.
The components of the base node are:
- compressor;
- evaporator;
- capacitor;
- throttle valve.
The compressor is responsible for “compressing” heat and moving it to consumers. The device itself requires an external power source.
The heat pump operates according to the following algorithm:
- The heat intake collector must contain a liquid inside that has a low freezing point. Often, when making geothermal heating with your own hands, water with a high salt content, alcohol diluted with water, and glycol mixtures are poured inside.
- In the evaporator module, heat is transferred to the refrigerant, which has a low boiling point, at which time it boils and turns into a vapor state.
- The compressor installed in the circuit increases the steam pressure, which results in an increase in the temperature of the substance to 78-80 0 C.
- Once the refrigerant substance enters the condenser, it enters the liquid phase, and at the same time energy is released for the heating circuit.
- The resulting liquid is returned to the compressor through the throttle valve.
Since a heat pump for heating a home operates on the principle of a refrigerator, it is often called a “reverse refrigerator.” In many cases, energy from the ground is used to install underfloor heating.
Correctly carried out calculations and well-executed installation of the heat exchanger can provide a fivefold increase in output power from one kilowatt consumed by the pump.
VIDEO: How a geothermal heat pump works
Heat exchanger installation
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The current installation types are the following:
- vertical, when you need to drill several wells;
- horizontal, where trenches are dug below the freezing depth;
- underwater, when laying is carried out along the bottom of the nearest body of water.
Well drilling
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To effectively use the thermal energy of the earth, if the area near the building is small, it is necessary to drill deep wells. A stable positive temperature remains several meters deep in the earth. The use of such geothermal wells provides heat to the heat exchanger circuit. This heat is then transferred to a second internal circuit located in the room.
Often, drilling several wells costs even less than laying them along the bottom of a reservoir. Thanks to this, the process becomes accessible to more people.
The process is carried out with a small-sized drilling rig and a small amount of auxiliary equipment. This practically does not affect the surrounding area. Construction of a well is allowed even in water, but it should not be closer than 2-3 m from a residential building.
The maximum usable depth is up to 200 m, but often efficiency appears from a level of 50 m. At the next stage, the well is equipped. A plastic tube with a diameter of 40 mm is placed inside the cavity. From one to four collector loops are passed into it.
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The cavity between the soil and the outer wall of the tube must be filled with heat-conducting material. The heating main is being wired and connected to the heat pump.
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This option is the most rational in terms of cost, since it does not require the preparation of trenches, foundation pits and other earthworks. But this capability is not available to everyone - the minimum volume of the reservoir is sufficient to heat a house of 100 sq.m. must be at least 200 cubic meters and located no further than 100 meters from the housing construction.
Pipes are laid along the bottom of reservoirs to prevent them from freezing during the peak of frost.
Carrying out calculations
To perform a system calculation, it is necessary to take into account the basic parameters:
- at a depth exceeding 15-20 m in central Russia, the temperature is maintained at +8-+10 0 C;
- for vertical structures, it is customary to take in calculations the resulting power value of 50 W per 1 m of height, and more accurate values depend on the degree of moisture in the rock, the presence of groundwater, etc.;
- dry rock gives 20-25 W/m;
- moistened clay or sandstone 45-55 W/m;
- hard granite rocks will provide up to 85 W/m;
- the presence of groundwater gives up to 110 W/m.
Using a Heat Pump
The longevity of the system depends on the characteristics and conditions in which the heat pump operates. In geothermal installations it is capable of operating approximately 1800 hours per year. This is the average value for latitudes without thermal underground springs.
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The operating principle of the thermal heating system is identical and has nothing to do with the country of origin or brand. Geothermal pumps may vary in design, size, appearance, but the heat production coefficient will always be the same for pumps from different companies and different countries. This is due precisely to the peculiarity of processing natural energy into heat.
The pump should not be used too much, as this process can lead to a significant decrease in the temperature of the soil around the well, and sometimes leads to its freezing.
The consequences of such miscalculations ultimately lead to disastrous consequences - the soil sags unevenly, in some places it goes very deep, as a result of which the protective plastic pipes are damaged. If the house is located nearby, deformation of the foundation or walls may occur due to geological changes.
Periodically, it is necessary to take measures to “regenerate” the soil, for which additional thermal energy is supplied to the heat exchanger. This can be the energy of a solar collector or heating a probe when a heat pump is used in room cooling mode.
In conclusion, it should be noted that geothermal installation is not yet available to everyone. In some cases, the payback period may last more than 10 years, but in the end, these methods of heating a house in the near future will become not just alternative, but the only possible ones.
VIDEO: Geothermal heat pumps
The development of any civilization is associated with meeting the requirements for one’s home. Wherever a person lived in a cave or a modern skyscraper, taking care of warmth and comfort was as important as obtaining food. Warming up with a small fire, stove or modern system For heating, he was forced to use firewood, coal, peat, diesel fuel, burning the priceless gifts of nature.
Technical development has made it possible to build powerful hydroelectric power stations, learn to use wind energy, and, having comprehended the secrets of the inner layers of the earth, think about creating alternative method using stored heat in the form of geothermal energy systems.
The fundamental operation of a geothermal heating system is based on the laws of physics discovered by scientists. The search for materials capable of changing their properties while releasing a certain amount of heat has made it possible to create not only ordinary refrigeration units, air conditioners, but also powerful
It is with their help that we can transfer the heat that always exists in the bowels of the earth to our home, carrying out coordinated control of the three special circuits that make up the heating system. The purpose of the external circuit is to collect 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, make it possible to obtain energy during the transition to a gaseous state. Moreover, the temperature coming from the external circuit is quite sufficient for this. The third internal circuit of the heating system represents the required number of radiators and pipes used in the house. It can be separate or common with the hot water supply circuit included in the project.
Functional features of the system
Operating principle and functional features geothermal heating systems for a home consist of the following steps:
- The solution located in the outer loop acquires additional heating in the ground by about 5 degrees. Its final temperature may be around 3.
- Having entered the heat exchanger of the pump, the solution transfers even its small energy to freon, for which it is quite enough for evaporation. Having passed into a gaseous state, freon enters the compressor, where it is compressed. The thermodynamic processes occurring in this case lead to a rise in temperature to 100. And the hot gas is supplied to the heat exchanger, where it transfers energy to the coolant of the internal circuit, most often water. Thanks to scientific work physicists and engineers, this process has been studied in detail and is embedded in the fundamental principles of work various types modern equipment.
- The coolant of the internal circuit reaches a temperature of 50-70 and enters the radiators and pipes. The cooled freon enters the expansion screen, its temperature and pressure drop to their original values and the entire cycle can be repeated again. The solution of the outer contour moves in the same way 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 resolved 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. In this case, 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 be located 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 most common types of heat exchangers are:
- Horizontal heat exchanger. This option can be considered as an effective proposal only if there is a large free area next to the house. It can only be used as a simple green lawn. Moreover, with a house area of, for example, 220 square meters. m. the heat exchanger will be located on an area of 600 sq.m. The pipes are laid in special trenches, the depth of which should be below the freezing level of the soil in this area.
- Vertical heat exchanger. From a space-saving point of view, this option, of course, has certain advantages. A problem may be the creation of special wells, the depth of which reaches 200 m, with a diameter of about 150 mm. Excavation work with drilling rigs is 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.
- Heat exchanger at the bottom of the reservoir. The most economical and simplest method for creating the outer loop 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.
- There is an option for an open heating system based on the use of water coming from an artesian well. It is passed through a heat pump as a coolant. To reverse the discharge of water, it is necessary to construct a second artesian well. But such a system is not possible in every place. At the same time very important factor is the return of water in the same amount to the deep layers of the soil to maintain pressure in the layers.
Interestingly, the first attempts to drill wells to harness heat were made in the mid-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 into his home.
The next step was also taken in Iceland and only in 1903 the first pipeline, 3 km long, appeared in Reykjavik. Currently, geothermal heating systems are very popular in many European countries, the USA, Mexico, Japan, and 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:
- This is the heat of the earth from shallow depths, used by heat pumps.
- The energy of hot steam, water in the earth's crust, currently used to produce electricity.
- Heat coming from deep layers without the presence of water and magma energy accumulated in volcanic zones.
- The use of this amazing gift of nature is determined only by the existing level of technology, technological capabilities and economic calculations.
Modern designs of geothermal heating systems have both positive and negative aspects.
The main negative point is the cost. But this only seems at the initial moment. All costs are recouped, according to various data, in 4, 5 years. This is due to the fact that modern heat pump models use much less energy to operate than any other heating system. When consuming 1 kW of electricity, their output is 5 kW.
Positive points:
- They do not burn fuel and do not produce harmful emissions of various compounds into the environment.
- Minimum maintenance costs with high efficiency.
- Environmental safety.
- Reliable properties fire safety systems.
Efficiency and payback
Geothermal energy cannot be called a free gift from nature. The creation of heating systems based on it can cost over a million rubles, excluding the cost of a heat pump. It all depends on the required heating volumes, its functional purpose and type. Usually economic feasibility geothermal heating systems are calculated by comparing the costs of its maintenance.
The cost of any type of energy used is not constant and will never decrease. In this regard, their alternative replacement by using the heat of the internal layers is, of course, economically profitable and expedient, since heat pumps do not consume a lot of energy, and to extract and process thermal reserves there is no need to build expensive factories and power plants.
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 systems supply, 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 nowadays. Of course, you can, especially off-road and into the forest to pick mushrooms. But you want it faster and more comfortably. So it is in this case. One thought that own system heating does not disturb the environment, does not interfere with the life of even the smallest and most unknown creatures in nature, which will confirm the correctness of choosing a geothermal system.
Installation and Installation
It is better to install such a heating system not on your own, but by involving specialists at least for individual species work with self-confidence.
The main stages are as follows:
- Calculation of the internal circuit 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.
- Calculation of the laying depth of external circuit pipes for the selected type of heat exchanger. It is necessary to take into account the geodetic data of the area.
- Drilling the required shaft and installing pipes. If there is no centralized water supply at the same time, the easiest way is to solve the issue of creating other water wells. The technology for their creation is different and requires special knowledge.
- Selection and installation of the required heat pump model.
- Installation automatic devices , monitoring the operation of the entire system and regulating the microclimate in any area of the room.
Pump overview: manufacturers and models
The effective functioning of the entire system is determined by the right choice heat pump. Based on their operating principles, pumps belong to a modern, environmentally friendly type of equipment. During their operation there is no release harmful substances 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 quite a 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 various 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 value of up to 500%, independent of external factors. Having started producing heat pumps since 1970, the company is constantly updating a large range modern models without losing high quality.
The new award-winning EcoTouch pump series confirms this fact. It includes models like DC 5027 with output power from 6 to 26 kW and convenient 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, m2 | Price, rubles |
| EcoTouch Ai 1 Geo | from 7.8 to 13.8 | 200-400 | 538 800 – 590 700 |
| EcoTouch DS 5027 AI | from 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 |
Review of prices for geothermal heating at home
A full calculation of the creation of a geothermal heating system can only be carried out according to a specific application, taking into account all the requirements. The right thing to do is to choose the nearest company working in this direction and work out all the details under the guidance of specialists. An example is the cost of a range of services Russian company"Geotherm-Comfort".
Cost of installation of geothermal heating:
| Heated area of the house (sq. m) | Heat pump power (kW) | Heat pump price (RUB) | The sum of all costs for installing an earthen circuit, including drilling wells and connecting a pump (rub.) | 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 industrial technologies used to create new equipment allow almost every owner of his own home to take advantage of the warmth of the deep layers of the earth. The importance of the possibility of reducing energy costs for 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. Because, ultimately, this is an undoubted gain and also concern for the environmental heritage of subsequent generations of our planet.
