Geothermal heating systems for a country house: do-it-yourself arrangement features

Operating principle

Such a phenomenon as geothermal heating, the principle of which resembles a conventional refrigerator, only in reverse, is becoming more and more popular. The earth retains heat constantly, it is possible to heat objects located on its surface. The bottom line is that hot magma heats the earth from the inside, and thanks to the soil it does not freeze from above.

And the principle of operation here is as follows: a heat pump is placed on top, a heat exchanger is lowered into a special earthen shaft. Ground water goes through the pump and is heated. Thus, the heat that is obtained in this case is used for industrial or domestic purposes. This is how ground heating works.

Schematic diagram of the heat pump

Note that the main advantage of such a system is that with an electricity cost of 1 kW, we obtain useful thermal energy in the range from 4 to 6 kW. For comparison, a conventional air conditioner is not able to convert 1 kW of electricity into 1 kW of thermal energy (the law of conservation of energy, since losses during the conversion of one type of energy to another, alas, has not been canceled yet). Heating from the heat of the earth will pay off quickly enough with the right approach to the implementation of geothermal heating.

Approximate costs and payback of the system

When choosing thermal heating, the principle of which is already known, the owners should be aware that certain investments will be required. The brand of equipment is selected according to the requirements of the user, the price of the units depends on many factors, for example, power.

Devices for 4-5 kW are estimated at $3000-7000, for 5-10 kW they cost $4000-8000, for 10-15 kW already $5000-10000. Plus, 40-50% of the amount will be the cost of installation work and the launch of the system. The result is a very impressive amount of costs. But all of them will pay off in about 3-5 years, and then only the electricity bills that the heat pump will consume remain.

The principle of obtaining geothermal energy

The operation of geothermal heating stations is often compared to the principle of operation of air conditioning systems or a conventional refrigerator. Any of the schemes consists of two heat exchange circuits. It is generally accepted that in the circuit located in the ground, the carrier is heated (most often non-freezing freon plays this role), which is subsequently transferred to the “home circuit” in the heat exchanger evaporator.

The liquid that has cooled down after circulating around the house must be heated again to about + 7 ° C to repeat the cycle. At the same time, in summer the system works on the opposite principle, cooling the air in the house, so it would be more correct to call it not heating, but air conditioning.

Using a heat pump

The durability 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 an average value for latitudes without thermal underground sources.

How a heat pump works

The principle of operation 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 thermal energy.

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, then 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 solar energy or probe heating when the heat pump is used in space cooling mode.

In conclusion, it should be noted that the geothermal installation is not yet available to everyone.In some cases, the payback period can last more than 10 years, but in the end, it is these methods of heating a house that will soon become not only alternative, but the only possible ones.

VIDEO: Geothermal heat pumps

Geothermal heating: we analyze the principle of operation

The principle of operation of this type of heating is quite simple and lies in the property of the earth not to freeze even at fairly low temperatures. For example, at an air temperature of about minus fifteen, the earth will freeze to only five to seven degrees. And now let's answer the question, is it possible to quite successfully extract the benefit from this property of the land and heat the house with the help of such a resource? The answer is obvious: of course, yes! So why not do it? The thing is, it's not all that simple. In order to install such heating, it is necessary to solve the associated small problems, which are listed below.

Geothermal heating installation

• To get the maximum heat out of the earth, you need to accumulate this very heat energy and concentrate it on heating the house, and this is worth some effort.
• It is necessary to maintain the temperature of the conductor. The heated riser must conduct heat in the fluids that will pass through the central heating system.
• If this conductor has cooled down, its temperature must be immediately restored by heating. To solve this trouble, special geothermal heat pumps were invented, which help to cope with the task.This device helps to extract the amount of heat necessary for normal heating of the house, which can be used for a variety of needs. By the way, such pumps are able to cope with fairly large volumes of work. The design possibilities directly depend on its location in the house.

If earlier such a phenomenon as heating a house with the help of the thermal energy of the earth could be found exclusively outside of our country, today such devices are not a miracle or a rarity.

The scheme of operation of thermal structures

At the same time, please note that they are installed not only in the southern, warm parts, as you might think. In the Northern regions, this is even more common.

Let's take a closer look at what kind of work scheme the structures have. A long time ago, people had a question why, when certain liquids evaporate from a surface, then the surface cools, and why energy is taken away. As soon as the answer to this question was given, the thought arose why not run this mechanism in the reverse order, that is, why not get warm air instead of ice. An example is the operation of modern air conditioning systems: many of them can not only cool, but also heat the air. The only disadvantage of such devices is their limited operation at low temperatures. At a certain temperature, they simply cannot work. Unlike them, the geothermal heating of a country house is completely devoid of such a drawback, although the principle of operation for them and for the aforementioned device is approximately the same.

Geothermal heating of a country house

Heat exchanger installation

The current installation types are:

• 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 reservoir.

This is interesting: Let's figure it out together - what is more efficient single-pipe or two-pipe heating system?

System installation

Geothermal heating of a country house at the stage of arrangement requires a solid financial investment. The high final 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.

• 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.

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 circuit is immersed in the wells (the most reliable option is pipes made of cross-linked polyethylene).

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

   Advantages: 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.

3. 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.

4. Disadvantages: The need to use a large area of ​​​​the site (the main disadvantage). This piece of land after laying the contour cannot be used for a garden or vegetable garden, as 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 yourself.

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.

Requirements for geothermal heating at home with your own hands

At first glance, it may seem that the installation costs are too high, however, using the installation for a long time, everyone will be able to make sure that this heating pays off quickly and does not require any investments.

Geoheating will require:

• One-time investment of a large amount of funds;
• Considerable forces for the arrangement;
• Correct and competent preparation.

In addition, one can note the regular increase in prices for resources such as gas and electricity, which occurs almost every month, but the geothermal system does not depend on these prices.

Part of the system has an underground location, due to which the earth is used as a heat source. Heating of this type will require a well, a probe and a heat exchanger. Only a device is installed on the territory of the house, due to which heat is generated and, as a rule, it does not require too much space. Due to this device, the temperature is regulated and heat energy is supplied. When installing the system, a small branching of pipes and a radiator is required, and if the building is small, then the generator is installed in the basement.

We install geothermal heating ourselves

The cost of the project and work to install a geothermal structure is quite significant, the purchase of all the necessary equipment, the involvement of a team of specialists, as well as the need for long-term excavation cannot be cheap.

However, due to the profitability of installing this type of heating in the house, the payback period is quite fast. Additional savings can be made by installing other sources of alternative energy production, such as solar panels that can power a geothermal network. Even with significant price hikes for fossil resources and gas, they will not affect the cost of heating.

The main part of the network of wires is hidden deep underground, a reservoir of refrigerant, which is placed in a well, supplies fuel to the house.Moreover, in the basement or other utility room, you will need to place a heat generator. Most of these devices are quite compact. To warm the premises will have to install several radiators.

On the installed generator it is possible to regulate the temperature in the house and the energy consumption. Installation is accompanied by the installation of equipment for heating rooms, branching of the pipeline. In most premises, the heat generator is taken out to a separate room so that the noise from work does not interfere with the residents doing their own business.

How to make geothermal heating with your own hands at home

Scheme of installation of a geothermal pump.

This is one of the most expensive and time-consuming types of heating. You have to carry out large-scale earthworks, the cost of equipment will make up the bulk of the costs. Before you start creating such heating with your own hands, you need to figure out which systems are used and what are the features of their device.

Materials required for installation of geothermal heating:

• polyethylene pipes;
• Heat pump;
• heating radiators.

Classification by type:

• the horizontal heat exchanger is used most often, while the pipes are laid in the ground to a depth exceeding the freezing level of the soil in your area. This type of heating has a significant drawback - the circuit occupies a large area. If the area of ​​​​your house is 250 m², then to heat it you will have to lay pipes on an area of ​​\u200b\u200babout 600 m², and this can not be done in every area. It is especially inconvenient to do such heating at home in the case when the territory is already ennobled, for example, the collector should be no closer than 1.5 m from the tree;
• the vertical heat exchanger has much smaller dimensions, but its cost is higher. To install it, you need a little space, but you will have to use drilling equipment.

The well can be from 50 to 200 m, but it will serve up to 100 years. This method is convenient when the territory of a country house is already equipped, there will be no need to change the existing landscape. Installing this type of geothermal heating completely with your own hands will not work, as you will need special equipment for drilling a well - a water-placed exchanger is the most economical way, it uses the thermal energy of water. Its use is possible if the distance to the reservoir is not more than 100 m. A spiral contour is made of pipes and laid to a depth exceeding the freezing zone, the area of ​​\u200b\u200bthe reservoir should be more than 200 m². When implementing this method, there is no need to carry out large-scale earthworks and therefore everything can be done by hand.

If we talk about the complexity of the implementation of this project, then it is quite large, and if you decide to do everything yourself, then the third method will be the most accessible. If you purchase expensive equipment, then the installation must be carried out with high quality, otherwise the system will not work normally.

Sources of geothermal heating

For geothermal heating, the following sources of terrestrial thermal energy can be used:

• high temperature;
• low temperature.

Thermal springs, for example, belong to high-temperature ones. You can use them, but their scope is limited by the actual location of such sources.If in Iceland this type of energy is actively used, then in Russia thermal waters are far from settlements. They are most concentrated in Kamchatka, where groundwater is used as a heat carrier and supplied to hot water systems.

A volcano is not needed to efficiently use the thermal energy of the earth. It is enough to use those resources that are only 200 meters from the earth's surface

But for the use of low-temperature sources, we have all the necessary prerequisites. For this purpose, the surrounding air masses, earth or water are suitable. A heat pump is used to extract the required energy. With its help, the procedure for converting the ambient temperature into thermal energy is carried out not only for heating, but also for hot water supply of a private household.

pros

The operation of such heating systems is carried out on a qualitatively new and unusual fuel - the energy of the bowels of the earth is used for air conditioning, as well as heating a private house. This energy creates optimal and comfortable living conditions, and does not pollute the environment with harmful substances and waste. The heating of the house is carried out using free energy, for 1 kW of electricity the system returns 4-5 kW of heat

An equally important advantage is that there is no need to purchase additional hoods and chimneys, which may be required to ensure the smooth functioning of other types of heating systems. During heating operation, harmful fumes and odors are not emitted from the ground, such a system does not make unnecessary noise, and besides, it does not take up much space.Geothermal units, unlike solid fuel and liquid fuel systems, are practically invisible to people, they do not destroy the integrity of the facade and interior of the house

There is no need to waste time thinking about issues such as storage, delivery and purchase of fuel, since the energy of the planet is inexhaustible

Geothermal units, unlike solid fuel and liquid fuel systems, are practically invisible to people, they do not destroy the integrity of the facade and interior of the house. There is no need to waste time thinking about issues such as storage, delivery and purchase of fuel, since the energy of the planet is inexhaustible.

If you need to heat your home with the warmth of the earth, then you should also consider its financial side. Immediately, we note that the process of installing such a system will require high costs compared to diesel and gas equipment.

In contrast to this, it can be noted that the level of electricity consumption is much less, so that in the long term, the economic feasibility of acquiring geothermal equipment is visible to the naked eye. According to the developers, up to five kilowatts of thermal energy will be returned from each kilowatt of electrical energy spent.