Let's try to explain in the language of a simple layman what is " HEAT PUMP«:

Heat pump - This is a special device that combines a boiler, a source of hot water supply and an air conditioner for cooling. The main difference between a heat pump and other heat sources is the ability to use renewable low-grade energy taken from environment(land, water, air, wastewater) to cover heat needs during the heating season, heat water for hot water supply and cool the house. Therefore, the heat pump provides a highly efficient energy supply without gas and other hydrocarbons.

Heat pump is a device that works like a reverse chiller, transferring heat from a low temperature source to a higher temperature environment, such as your home's heating system.

Each heat pump system has the following main components:

- primary circuit - a closed circulation system that serves to transfer heat from the ground, water or air to the heat pump.
- secondary circuit - a closed system that serves to transfer heat from the heat pump to the heating, hot water or ventilation system (inflow heating) in the house.

How a heat pump works similar to the operation of an ordinary refrigerator, only in reverse. The refrigerator takes heat from food and transfers it outside (to a radiator located on its back wall). A heat pump, on the other hand, transfers the heat accumulated in the soil, earth, reservoir, groundwater or air into your home. Like a refrigerator, this energy-efficient heat generator has the following main elements:

- a condenser (a heat exchanger in which heat is transferred from the refrigerant to the elements of the room heating system: low-temperature radiators, fan coil units, warm floor, radiant heating/cooling panels);
- throttle (a device that serves to reduce pressure, temperature and, as a result, close the heating cycle in the heat pump);
- evaporator (heat exchanger in which heat is taken from a low-temperature source to a heat pump);
- compressor (a device in which the pressure and temperature of the refrigerant vapor increases).

Heat pump arranged in such a way as to make the heat move in different directions. For example, during the heating of a house, heat is taken from some cold external source (land, river, lake, outdoor air) and transferred to the house. To cool (condition) the house, heat is taken from the warmer air in the house and transferred to the outside (discharged). In this respect, a heat pump is similar to a conventional hydraulic pump, which pumps liquid from the lower level to the upper level, while in normal conditions the liquid always moves from the upper level to the lower one.

Today, the most common are vapor compression heat pumps. The principle of their operation is based on two phenomena: firstly, the absorption and release of heat by the liquid during the change state of aggregation are evaporation and condensation, respectively; secondly, the change in the temperature of evaporation (and condensation) with a change in pressure.

In the evaporator of a heat pump, there is a working fluid - a refrigerant that does not contain chlorine - it is under low pressure and boils at a low temperature, absorbing heat from a low-grade source (for example, soil). Then the working fluid is compressed in the compressor, which is driven by an electric or other motor, and enters the condenser, where high pressure condenses at more high temperature, giving off the heat of condensation to a heat receiver (for example, the heat carrier of a heating system). From the condenser, the working fluid through the throttle again enters the evaporator, where its pressure decreases, and the refrigerant boiling process begins anew.

Heat pump capable of extracting heat from various sources e.g. air, water, soil. Also, it can release heat into air, water or ground. A warmer environment that receives heat is called a heat sink.

Heat pump X/Y uses medium X as heat source and Y heat carrier. A distinction is made between pumps "air-to-water", "soil-to-water", "water-to-water", "air-to-air", "soil-to-air", "water-to-air".

Heat pump "ground-water":

Air-to-water heat pump:

The regulation of the heating system using heat pumps in most cases is carried out by turning it on and off at the signal of a temperature sensor that is installed in the receiver (when heating) or the source (when cooling) of heat. The heat pump is usually tuned by changing the cross section of the throttle (thermal expansion valve).

Like a refrigeration machine, a heat pump uses mechanical (electrical or other) energy to implement a thermodynamic cycle. This energy is used to drive the compressor (modern heat pumps up to 100 kW are equipped with highly efficient scroll compressors).

(transformation ratio or efficiency) of a heat pump is the ratio of the amount of thermal energy that the heat pump produces to the amount electrical energy that it consumes.

COP conversion factor depends on the temperature level in the evaporator and condenser of the heat pump. This value varies for various heat pump systems in the range from 2.5 to 7, that is, for 1 kW of electrical energy consumed, the heat pump generates from 2.5 to 7 kW of thermal energy, which is beyond the power of either a condensing gas boiler or any other generator heat.

Therefore, it can be argued that heat pumps produce heat using minimal amount expensive electrical energy.

The energy saving and efficient use of a heat pump primarily depends on from where you decide to draw low-temperature heat, secondly - from the method of heating your house (water or air) .

The fact is that the heat pump works as a “transshipment base” between two thermal circuits: one heating at the inlet (on the evaporator side) and the second heated at the outlet (condenser).

All types of heat pumps are characterized by a number of features that you need to remember when choosing a model:

Firstly, a heat pump justifies itself only in a well-insulated house. The more warm house, the greater the benefit when using this device. As you understand, it is not entirely reasonable to heat the street with a heat pump, collecting crumbs of heat from it.

Second, than more difference temperatures of heat carriers in the inlet and outlet circuits, the lower the heat conversion coefficient (COP), that is, the lower the saving of electrical energy. That is why more profitable connection of the heat pump to low-temperature heating systems. First of all, we are talking about heating with a water-heated floor or infrared water ceiling or wall panels. But the more hot water the heat pump prepares for the outlet circuit (radiators or shower), the less power it develops and the more electricity it consumes.

Thirdly, in order to achieve greater benefits, the operation of a heat pump with an additional heat generator is practiced (in such cases, one speaks of using bivalent heating scheme ).

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Heat pumps for home heating: pros and cons

1. Features of heat pumps
2. Types of heat pumps
3. Geothermal type heat pumps
4. Advantages and disadvantages of heat pumps

One of the highly efficient ways of heating a country house is the use of heat pumps.

The principle of operation of heat pumps is based on the extraction of thermal energy from the soil, reservoirs, groundwater, and air. Heat pumps for home heating do not have a harmful effect on the environment. How similar heating systems look like can be seen in the photo.

Such an organization of home heating and hot water supply has been possible for many years, but it has only recently begun to spread.

Features of heat pumps

The principle of operation of such devices is similar to refrigeration equipment.

Heat pumps take heat, accumulate it and enrich it, and then transfer it to the heat carrier. A condenser is used as a heat generating device, and an evaporator is used to recover low potential heat.

The constant increase in the cost of electricity and the presentation of stringent requirements for environmental protection is the reason for the search for alternative methods of obtaining heat for heating houses and heating water.

One of them is the use of heat pumps, since the amount of heat energy received is several times higher than the electricity consumed (for more details: “Economical heating with electricity: pros and cons”).

If we compare heating with gas, solid or liquid fuels, with heat pumps, then the latter will be more economical. However, the very arrangement of the heating system with such units is much more expensive.

Heat pumps consume the electricity needed to run the compressor. Therefore, this type of building heating is not suitable if there are frequent problems with power supply in the area.

Heating a private house with a heat pump can have different efficiency, its main indicator is the conversion of heat - the difference between the electricity consumed and the heat received.

The difference between the temperature of the evaporator and the condenser is always present.

The larger it is, the lower the efficiency of the device. For this reason, when using a heat pump, you need to have a considerable source of low potential heat. Based on this, it follows that the larger the size of the heat exchanger, the lower the energy consumption. But at the same time, devices with large dimensions have a much higher cost.

Heating with a heat pump is found in many developed countries.

Moreover, they are also used to heat multi-apartment and public buildings - this is much more economical than the usual heating system in our country.

Types of heat pumps

These devices can be used over a wide temperature range. Usually they work normally at temperatures from -30 to + 35 degrees.

The most popular are absorption and compression heat pumps.

The latter of them use mechanical and electrical energy to transfer heat. Absorption pumps are more complex, but they are able to transfer heat using the source itself, thereby significantly reducing energy costs.

As for heat sources, these units are divided into the following types:

  • air;
  • geothermal;
  • secondary heat.

Air source heat pumps for heating take heat from the surrounding air.

Geothermal heating systems use the thermal energy of the earth, underground and surface waters (for more details: "Geothermal heating: the principle of operation with examples"). Secondary heat pumps take energy from sewage, central heating - these devices are mainly used for heating industrial buildings.

This is especially beneficial if there are sources of heat that must be disposed of (read also: "Using the heat of the earth to heat the house").

Heat pumps are also classified according to the types of coolant, they can be air, soil, water, as well as their combinations.

Geothermal heat pumps

Heating systems that use heat pumps are divided into two types - open and closed. Open structures are designed to heat the water passing through the heat pump. After the coolant passes through the system, it is discharged back into the ground.

Such a system works ideally only if there is a significant amount of clean water, given the fact that its consumption will not harm the environment and will not conflict with current legislation. Therefore, before using a heating system that receives energy from groundwater, you should consult with the relevant organizations.

Closed systems are divided into several types:

  1. Horizontal geothermal systems mean laying the collector in a trench below the freezing depth of the soil.

    This is approximately 1.5 meters. The collector is laid in rings in order to reduce the earthwork area to a minimum and provide a sufficient circuit in a small area (read: "Geothermal heat pumps for heating: the principle of the system design").

    This method is only suitable if there is a sufficient free area of ​​​​the site.

  2. Geothermal structures with a vertical arrangement provide for the placement of a collector in a well up to 200 meters deep. This method is used when it is not possible to locate the heat exchanger over a large area, which is necessary for a horizontal well.

    Also, geothermal systems with vertical wells are made in the case of an uneven landscape of the site.

  3. Geothermal water systems involve placing a collector in a reservoir at a depth below the freezing level. Laying is done in rings. Such systems cannot be used if the reservoir is small or not deep enough.

    It must be borne in mind that if the reservoir freezes at the level where the collector is located, the pump will not be able to work.


Heat pump air water - features, details on the video:

Advantages and disadvantages of heat pumps

Heating a country house with a heat pump has both positive and negative sides. One of the main advantages of heating systems is environmental friendliness.

Also, heat pumps are economical, unlike other heaters that consume electricity. Thus, the amount of generated thermal energy is several times greater than the consumed electricity.

Heat pumps are characterized by increased fire safety, they can be used without creating additional ventilation.

Since the system has a closed circuit, financial expenses during operation are minimized - you have to pay only for the consumed electricity.

The use of heat pumps also allows you to cool the room in the summer - this is possible due to the connection of fan coils to the collector and the "cold ceiling" system.

These devices are reliable, and the control of the work processes is fully automatic. Therefore, the operation of heat pumps does not require special skills.

The compact dimensions of the devices are also important.

The main disadvantage of heat pumps:

  • high cost and significant installation costs. It is unlikely that you will be able to design heating with a heat pump with your own hands without special knowledge. It will take more than one year for the investment to pay off;
  • the service life of the devices is approximately 20 years, after which it is highly likely that a major overhaul will be required.

    This, too, will cost dearly;

  • the price of heat pumps is several times higher than the cost of gas, solid or liquid fuel boilers. A lot of money will have to be paid for drilling wells.

But on the other hand, heat pumps do not require regular maintenance, as is the case with many other heating appliances.

Despite all the advantages of heat pumps, they are still not widely used. This is due, first of all, to the high cost of the equipment itself and its installation. It will be possible to save money only if you create a system with a horizontal heat exchanger, if you dig trenches yourself, but this will take more than one day. As for the operation, the equipment is very profitable.

Heat pumps are an economical way to heat buildings without harming the environment.

They cannot be widely used due to the high cost, but this may change in the future. In developed countries, many owners of private houses use heat pumps - there the government encourages concern for the environment, and the cost of this type of heating is low.

A thermal ground or geothermal pump is one of the most energy efficient alternative energy systems. Its operation does not depend on the time of year and ambient temperature, as for an air-to-air pump, it is not limited by the presence of a reservoir or a well with groundwater near the house, like a water-to-water system.

The ground-to-water heat pump, which uses the heat taken from the soil to heat the coolant in the heating system, has the highest and constant efficiency, as well as the energy conversion coefficient (COP).

Its value is 1:3.5-5, that is, each kilowatt of electricity spent on the operation of the pump is returned by 3.5-5 kilowatts of thermal energy. Thus, the heating power of a soil pump makes it possible to use it as the only source of heat even in a house with a large area, of course, when installing a unit of appropriate power.

A submersible soil pump requires equipment of a soil circuit with a circulating coolant to extract the heat from the earth.

There are two options for its placement: a horizontal soil collector (a system of pipes at a shallow depth, but a residually large area) and a vertical probe placed in a well from 50 to 200 m deep.

The efficiency of heat exchange with the soil significantly depends on what kind of soil lies - moisture-filled soil gives off much more heat than, for example, sandy soil.

The most common are pumps operating on the principle of ground-water, in which the coolant stores the energy of the soil and, as a result of passing through the compressor and heat exchanger, transfers it to water as a heat carrier in the heating system. Prices for soil pumps of this type correspond to their high efficiency and performance.


Submersible Soil Pump

Any complex high-tech units, such as GRAT ground pumps, as well as ground source heat pumps, require the attention of professionals.

Heat pump

We offer a full range of services for the implementation, installation and maintenance of heating and hot water systems based on heat pumps.

To date, European countries and China are especially popular among the producing countries of such units on the market.

The most famous models of heat pumps: Nibe, Stiebel Eltron, Mitsubishi Zubadan, Waterkotte. The domestic ground heat pump is no less in demand.

Our company prefers to work only with equipment from reliable European manufacturers: Viessmann and Nibe.

The heat pump extracts the accumulated energy from various sources - ground, artesian and thermal waters - waters of rivers, lakes, seas; purified industrial and domestic wastewater; ventilation emissions and flue gases; soil and the earth's interior - transfers and converts into energy at higher temperatures.

Heat pump – highly economical, environmentally friendly technology for heating and comfort

Thermal energy exists all around us, the problem is how to extract it without spending significant energy resources.

Heat pumps extract the accumulated energy from various sources - ground, artesian and thermal waters - waters of rivers, lakes, seas; purified industrial and domestic wastewater; ventilation emissions and flue gases; soil and the earth's interior - transfers and converts into energy at higher temperatures.

The choice of the optimal heat source depends on many factors: the size of the energy needs of your home, the installed heating system, the natural conditions of the region where you live.

The device and principle of operation of the heat pump

The heat pump functions like a refrigerator - just the other way around.

The refrigerator transfers heat from the inside to the outside.

The heat pump transfers the heat stored in the air, soil, subsoil or water into your home.

The heat pump consists of 4 main units:

Evaporator,

Capacitor,

Expansion valve (discharge valve-
throttle, lowers pressure),

Compressor (increases pressure).

These units are connected by a closed pipeline.

The piping system circulates a refrigerant that is a liquid in one part of the cycle and a gas in the other.

Earth's interior as a deep heat source

The earth's interior is a free heat source that maintains the same temperature all year round.

The use of the heat of the earth's interior is an environmentally friendly, reliable and safe technology for providing heat and hot water to all types of buildings, large and small, public and private. The level of investment is quite high, but in return you will receive a safe to operate, with minimal maintenance requirements, an alternative heating system with the longest possible service life. Heat conversion coefficient (see.

page 6) is high, reaches 3. The installation does not require much space and can be implemented on a small plot of land. The volume of restoration work after drilling is insignificant, the impact of the drilled well on the environment is minimal. There is no impact on the groundwater level as groundwater is not consumed. Thermal energy is transferred to the convection water heating system and used for hot water supply.

Ground heat - nearby energy

Heat accumulates in the surface layer of the earth during the summer.

The use of this energy for heating is advisable for buildings with high energy costs. The greatest amount of energy is extracted from soil with a high moisture content.

Ground source heat pump

Water heat sources

The sun heats water in the seas, lakes and other water sources.

Solar energy accumulates in water and bottom layers. Rarely the temperature drops below +4 °C. The closer to the surface, the more the temperature varies throughout the year, while at depth it is relatively stable.

Heat pump with water heat source

The heat transfer hose is laid on the bottom or in the bottom soil, where the temperature is still slightly higher,
than water temperature.

It is important that the hose be fitted with a weight to prevent
hose rises to the surface. The lower it lies, the lower the risk of damage.

The water source as a heat source is very efficient for buildings with relatively high heat demand.

Groundwater heat

Even groundwater can be used to heat buildings.

This requires a drilled well, from where water is pumped into the heat pump.

When using ground water, high demands are placed on its quality.

Ground water heat pump as heat source

After passing through the heat pump, water can be transported to a drainage channel or a well. Such a solution may lead to an undesirable decrease in the groundwater level, as well as reduce the operational reliability of the installation and have a negative impact on nearby wells.

Now this method is used less and less.

Groundwater can also be returned to the ground also through partial or complete infiltration.

Such a good heat pump

Heat conversion coefficient

The higher the efficiency of the heat pump, the more profitable it is.

Efficiency is determined by the so-called heat conversion coefficient or thermal transformation coefficient, which is the ratio of the amount of energy generated by the heat pump to the amount of energy spent on the heat transfer process.

For example: The temperature transformation coefficient is 3.

This means that the heat pump delivers 3 times more energy than it consumes. In other words, 2/3 is received "for free" from the heat source.

How to make a heat pump for home heating with your own hands: the principle of operation and schemes

The higher the energy demand of your home, the more money you save.

Note The value of the temperature transformation coefficient is affected by the presence/ignorance in the calculations of the parameters of additional equipment (circulation pumps), as well as various temperature conditions.

The lower the temperature distribution, the higher the temperature transformation coefficient becomes, heat pumps are most efficient in heating systems with low temperature characteristics.

When selecting a heat pump for your heating system, it is unprofitable to orient
power indicators of the heat pump for the maximum power requirements (to cover the energy consumption in the heating circuit on the coldest day of the year).

Experience shows that the heat pump should generate about 50-70% of this maximum, the heat pump should cover 70-90% (depending on the heat source) of the total annual energy demand for heating and hot water supply. At low external temperatures, the heat pump is used with the available boiler equipment or the peak closer, which the heat pump is equipped with.

Comparison of the costs of installing a heating system for an individual house based on a heat pump and a liquid fuel boiler.

For analysis, let's take a house with an area of ​​​​150-200 sq.m.

The most common variant of a modern country house for permanent use today.
The use of modern building materials and technologies ensures the amount of heat loss of the building at the level of 55 W/sq.m of floor.
To cover the total needs for thermal energy spent on heating and hot water supply of such a house, it is necessary to install a heat pump or boiler with a thermal output of approximately 12 kW / h.
The cost of the heat pump itself or the oil-fired boiler is only a fraction of the costs that must be incurred to commission the heating system as a whole.

The following is a far from complete list of the main associated costs for the installation of a turnkey heating system based on an oil-fired boiler, which are absent in the case of a heat pump:

air vent filter, fixed package, safety group, burner, boiler piping system, weather-compensated automatic control panel, emergency electric boiler, fuel tank, chimney, boiler.

All this in total is at least 8000-9000 euros. Taking into account the need to arrange the boiler room itself, the cost of which, taking into account all the requirements of the supervisory authorities, is several thousand euros, we come to a conclusion that is paradoxical at first glance, namely, the practical comparability of the initial capital costs when installing a turnkey heating system based on a heat pump and a liquid fuel boiler.

In both cases, the cost is close to 15 thousand euros.

Given the following undeniable advantages of a heat pump, such as:
Profitability. With the cost of 1 kW of electricity 1 ruble 40 kopecks, 1 kW of thermal power will cost us no more than 30-45 kopecks, while 1 kW of thermal energy from the boiler will cost 1 ruble 70 kopecks (with the price of diesel fuel 17 rubles / l);
Ecology. Environmentally friendly heating method for both the environment and people in the room;
Safety. There is no open flame, no exhaust, no soot, no smell of diesel fuel, no gas leakage, no fuel oil spill.

There are no fire hazardous storages for coal, firewood, fuel oil or diesel fuel;

Reliability. A minimum of moving parts with a high resource of work. Independence from the supply of furnace material and its quality. Virtually maintenance free. The service life of the heat pump is 15 - 25 years;
Comfort. The heat pump operates silently (no louder than a refrigerator);
Flexibility. The heat pump is compatible with any circulating heating system, and the modern design allows it to be installed in any room;

An increasing number of owners of individual houses choose a heat pump for heating both in new construction and when upgrading an existing heating system.

Heat pump device

The near-surface technology of using low-potential thermal energy with the help of a heat pump can be considered as some kind of technical and economic phenomenon or a real revolution in the heat supply system.

Heat pump device. The main elements of a heat pump are the evaporator, compressor, condenser and flow regulator connected by a pipeline - a choke, expander or swirl tube (Fig. 16).

Schematically, a heat pump can be represented as a system of three closed circuits: in the first, external, a heat sink circulates (a heat carrier that collects the heat of the environment), in the second - a refrigerant (a substance that evaporates, taking away the heat of the heat sink, and condenses, giving off heat to the heat sink) , in the third - a heat sink (water in the heating and hot water supply systems of the building).

16. Heat pump device

The external circuit (collector) is a pipeline laid in the ground or in water, in which an antifreeze liquid circulates. It should be noted that both natural heat (outside air; heat of ground, artesian and thermal waters; waters of rivers, lakes, seas and other non-freezing natural reservoirs) and technogenic origin (industrial discharges, treatment facilities, heat from power transformers and any other waste heat).

The temperature required for the operation of the pump is usually 5-15 .

The second circuit, where the refrigerant circulates, has built-in heat exchangers - an evaporator and a condenser, as well as devices that change the pressure of the refrigerant - a throttle spraying it in the liquid phase (a narrow calibrated hole) and a compressor compressing it already in the gaseous state.

Working cycle. The liquid refrigerant is forced through the throttle, its pressure drops, and it enters the evaporator, where it boils, taking away the heat supplied by the collector from the environment.

Further, the gas into which the refrigerant has turned is sucked into the compressor, compressed and, heated, is pushed into the condenser. The condenser is the heat dissipating unit of the heat pump: here the heat is received by the water in the heating circuit system. The gas is then cooled and condensed in order to be again depressurized in the expansion valve and returned to the evaporator. After that, the work cycle is repeated.

In order for the compressor to work (maintain high pressure and circulation), it must be connected to electricity.

But for every kilowatt-hour of electricity consumed, the heat pump produces 2.5-5 kilowatt-hours of thermal energy.

Heat pump for heating: principle of operation and advantages of use

This ratio is called the transformation ratio (or heat conversion ratio) and serves as an indicator of the efficiency of the heat pump.

The value of this value depends on the difference between the temperature levels in the evaporator and the condenser: the greater the difference, the smaller it is. For this reason, the heat pump should use as much of the low-grade heat source as possible without trying to cool it down too much.

Types of heat pumps.

Heat pumps come in two main types - closed and open circuit.

Open circuit pumps they use water from underground sources as a heat source - it is pumped through a drilled well into a heat pump, where heat exchange takes place, and the cooled water is discharged back into the underwater horizon through another well.

This type of pump is beneficial in that groundwater maintains a stable and fairly high temperature all year round.

Closed circuit pumps there are several types: vertical and g horizontal(Fig.17).

Pumps with a horizontal heat exchanger have a closed external circuit, the main part of which is dug horizontally into the ground, or laid along the bottom of a nearby lake or pond.

The depth of the pipes underground in such installations is up to a meter. This method of obtaining geothermal energy is the cheapest, but its use requires a number of technical conditions that are not always available in the developed area.

The main one is that the pipes should be laid so as not to interfere with the growth of trees, agricultural work, so that there is a low probability of damage to underwater pipes during agricultural or other activities.


Rice. 17. Surface geothermal system with heat exchange

Pumps with vertical heat exchanger include an external contour dug deep into the ground - 50-200 m.

This is the most efficient type of pump and produces the cheapest heat, but it is much more expensive to install than the previous types. The benefit in this case is due to the fact that at a depth of more than 20 meters, the temperature of the earth is stable all year round and is 15-20 degrees, and it only grows with increasing depth.

Air conditioning with heat pumps. One of the important qualities of heat pumps is the ability to switch from heating mode in winter to air conditioning mode in summer: only fan coil units are used instead of radiators.

A fancoil is an indoor unit into which a heat or coolant is supplied and air driven by a fan, which, depending on the water temperature, is either heated or cooled.

Includes: heat exchanger, fan, air filter and control panel.

Since fan coil units can operate both for heating and for cooling, several piping options are possible:
- S2 - pipe - when water plays the role of heat and coolant and their mixing is allowed (and, as an option, a device with an electric heater and a heat exchanger that works only for cooling);
- S4 - pipe - when the coolant (for example, ethylene glycol) cannot be mixed with the coolant (water).

The power of fan coil units for cold ranges from 0.5 to 8.5 kW, and for heat - from 1.0 to 20.5 kW.

They are equipped with low-noise (from 12 to 45 dB) fans with up to 7 rotation speeds.

Perspectives. The widespread use of heat pumps is hampered by insufficient public awareness. Potential buyers are frightened by rather high initial costs: the cost of the pump and installation of the system is $ 300-1200 per 1 kW of required heating power. But a competent calculation convincingly proves the economic feasibility of using these installations: investments pay off, according to rough estimates, in 4-9 years, and heat pumps serve for 15-20 years before major repairs.

The World Energy Committee has made a forecast for the use of heat sources for heating buildings for 2020. It states that in developed countries, 75% of homes will receive hot water and be heated by the geothermal energy of our planet.

To date, 40% of all new homes in Switzerland are equipped with heat pumps, and in Sweden this figure has been increased to 90%. Russia and the CIS countries are less introducing a heat pump for home heating, although the first enthusiasts are already using this method, passing on their experience to followers.

Work principles

To heat the building, the transfer of energy from a source of low potential (temperature) by a heat carrier to a consumer is used. The technological process uses the law of thermodynamics, which ensures the equalization of the thermal energies of two systems with different temperatures: transferring the power of a hot source to a cold consumer.

When using the heat of the environment, its temperature potential is increased for heating and hot water supply.

The source of regenerative heat can be:

  • the surface of the earth or its volume;
  • aquatic environment (lake, river);
  • air masses.

More popular are models that take energy from the earth, the surface of which is heated by the sun's rays and the energy of the outer and inner core of the planet. They are marked:

  1. the best combination of consumer qualities;
  2. efficiency;
  3. price.

Heat transfer circuits

During the operation of a heat pump (HP), three closed circuits are used, through which various liquids / gases - heat carriers circulate. Each of them performs its functions.

Source Energy Potential Pickup Loop

When taking in air heat, artificial blowing of the evaporator body with air flows from fans is used.

A closed cycle of a liquid heat carrier for transferring the heat of the aquatic environment or the earth is carried out through pipelines that connect the evaporator coil with a collector recessed to the bottom of the reservoir or buried in the ground at a distance exceeding the freezing of the soil in extreme cold.

Non-freezing liquids based on diluted aqueous solutions of alcohol are used as a heat carrier. They are called "antifreezes" or "brines". Under the influence of a higher temperature (≥ + 3ºС), they rise to the evaporator, transfer heat to it, and after cooling (≈-3ºС), they go back to the energy source by gravity, providing continuous circulation.

Inner contour

Freon-based refrigerant circulates through it, “raising” the heat to a higher level. Under the action of temperature, it successively passes into a gaseous and liquid state.

The internal circuit includes:

  • an evaporator that takes energy from brines and transfers it to freon, which boils and becomes a rarefied gas;
  • a compressor that compresses gas to high pressure. At the same time, the temperature of freon increases sharply;
  • a condenser in which the hot gas transfers its energy to the coolant of the outlet circuit, while it cools down, turning into a liquid state;
  • a throttle (expansion valve) that reduces freon due to a pressure drop to a state of saturated steam to enter the evaporator. When the refrigerant passes through a narrow hole, the coolant pressure drops to its initial value.

output circuit

Water circulates here. It is heated in a condenser coil for use in a conventional hydronic heating system. With this method, its temperature reaches about 35ºС, which determines its use in the "Warm floor" system with long pipelines, which allow the generated energy to be evenly transferred to the entire volume of the room.

Using only heating radiatorscreating smaller volumes of heat exchange with the space of rooms is not so effective.

Design

The industry produces models of various performance characteristics, but they include equipment that performs the typical tasks described above.

As a variant of the design, the figure shows a heat pump for heating a house.

Here, heat from geothermal sources is received through the inlet pipelines, and on weekends it is transferred to the heating system of the house.

The operation of the heat pump is ensured by:

  • a system for monitoring circuit parameters and control, including remote methods via the Internet;
  • additional equipment (washing and filling units, expansion tanks, safety groups, pumping stations).

Ground structures

They use three schemes for the design of heat exchangers to take energy from a source:

  1. surface location;
  2. installation of vertical ground probes;
  3. deepening of horizontal structures.

The first method is the least efficient. Therefore, it is rarely used for home heating.

Installation of probes in wells

This method is the most efficient. It provides for the creation of wells at depths of the order of 50÷150 meters or more to accommodate a U-shaped pipeline made of plastic materials with a diameter of 25 to 40 mm.

Increasing the cross-sectional area of ​​the pipe, as well as deepening the well, creates improved heat removal, but increases the cost of the design.

Horizontal collectors

Drilling wells for probes is expensive. Therefore, this method is often chosen as cheaper. It allows you to get by with digging trenches below the freezing depth of the soil.

In the design of a horizontal collector, the following should be taken into account:

  1. soil thermal conductivity;
  2. average soil moisture;
  3. area geometry.

They affect the dimensions and configuration of the collector. Pipes can be laid:

  • loops;
  • zigzags;
  • snake;
  • flat geometric shapes;
  • screw spirals.

It is important to understand that the area of ​​​​the site allocated for such a collector usually exceeds the dimensions of the foundation of the house by 2–3 times. This is the main disadvantage of this method.

Water collectors

This is the most economical method, but it requires a location near a deep water building. At its bottom, the assembled pipelines are placed and secured with loads. For the efficient operation of the heat pump, it is necessary to calculate the minimum depth of the collector and the volume of the reservoir capable of providing heat removal.

The dimensions of this design are determined by thermal calculations and can reach a length of more than 300 meters.

The figure below shows the preparation of highways for assembly on the ice of a spring lake. It allows you to visually assess the scope of the work ahead.

air method

An external or built-in fan blows air from the street directly to the freon evaporator, as in an air conditioner. At the same time, it is not required to create bulky structures from pipes and place them in the ground or a reservoir.

A heat pump for heating a house that works according to this principle is cheaper, but it is recommended to use it in a relatively warm climate: frosty air will not allow the system to work.

Such devices are widely used for heating water in pools or rooms located next to industrial devices that are constantly involved in the technological process and release heat into the atmosphere with powerful cooling systems. As an example, power autotransformers of the energy industry, diesel stations, and boiler houses can be cited.

Main characteristics

When choosing a TN model, consider:

  • output thermal power;
  • coefficient of transformation of heat pumps;
  • conditional efficiency;
  • annual efficiency and costs.

output power

When creating a new house project, its heat needs are taken into account, taking into account the design features of materials that create heat loss through walls, windows, doors, ceilings and floors of rooms of various sizes. The calculation takes into account the creation of comfort at the lowest frosts in a particular area.

The heat input of the building is expressed in kW. It must be covered by the generated energy from the heat pump. However, a simplification is often made in calculations that allows savings: the duration of the coldest days during the year does not exceed several weeks. For this period, an additional heat source is connected, for example, heating elements that heat water in the boiler.
They work only in critical situations during frosts, and are disabled the rest of the time. This allows the use of VTs with smaller capacities.

Design possibilities

For reference. Models of output power 6÷11 kW of "brine-water" circuits are able to heat the water of built-in tanks in relatively small buildings. A power of 17 kW is sufficient to maintain a water temperature of 65ºС for a boiler with a capacity of 230÷440 liters.
The heat demand of medium-sized buildings covers capacities of 22÷60 kW.

Heat pump transformation ratio Ktr

It determines the efficiency of the structure by the dimensionless formula:

Ktr=(Tout-Tin)/Tout

The value of "T" indicates the temperature of the coolants at the outlet and inlet to the structure.

Energy Conversion Factor (ͼ)

It is calculated to determine the proportion of useful heat output in relation to the applied energy per compressor.

ͼ=0.5Т/(Т-То)=0.5(ΔТ+То)/ΔТ

For this formula, the temperature of the consumer "T" and the source "To" is determined in degrees Kelvin.

The value of ͼ can be determined by the amount of energy expended for the operation of the "Rel" compressor and the obtained useful heat output "Рн". In this case, it is called "COP", short for the English term "Coefficient of performance".

The coefficient ͼ is a variable value dependent on the temperature difference between the source and the consumer. It is numbered from 1 to 7.

Conditional efficiency

This is an incorrect statement: the efficiency takes into account the power losses during the operation of the final device.
To determine it, it is necessary to divide the output thermal power by the applied one, taking into account the energy of geothermal sources. With such a calculation, a perpetual motion machine will not work.

Annual efficiency and costs

The COP coefficient evaluates the performance of a heat pump at a certain point in time under specific operating conditions. In order to analyze the operation of the HP, an indicator of the efficiency of the system for the year (β) was introduced.

Here the symbol Qwp denotes the amount of thermal energy produced in a year, and Wel - the value of electricity consumed by the installation during the same time.

Cost indicator Eq

This characteristic is the opposite of the efficiency indicator.

To determine the characteristics of the HP, specialized software and factory stands are used.

Distinctive features

Advantages

Heating a house with a heat pump, in comparison with other systems, has:

  1. good environmental parameters;
  2. long service life of equipment without maintenance;
  3. the possibility of simply switching the heating mode in winter to air conditioning in summer;
  4. high annual efficiency.

Flaws

At the design stage and during operation, it is necessary to take into account:

  1. the difficulty of performing accurate technical calculations;
  2. high cost of equipment and installation work;
  3. the possibility of the formation of "air locks" in case of violations of the technology of laying pipelines;
  4. limited water temperature at the outlet of the system (≤+65ºС);
  5. strict individuality of each design for any building;
  6. the need for large areas for collectors with the exception of the construction of facilities on them.

Short list of manufacturers

A modern heat pump for home heating is produced by companies such as:

  • Bosch - Germany;
  • Waterkotte - Germany;
  • WTT Group OY - Finland;
  • ClimateMaster - USA;
  • ECONAR - USA;
  • Dimplex - Ireland;
  • FHP Manufacturing - USA;
  • Gustrowr - Germany;
  • Heliotherm - Austria;
  • IVT - Sweden;
  • LEBERG - Norway.

Heat pump- a mechanical device that allows to ensure the transfer of heat from a resource with low potential thermal energy (with a low temperature) to a heating system (heat carrier) with an elevated temperature. Let's try to explain this in a more understandable language.

Gone are the days when a person heated his home by burning wood in fireplaces or stoves. Replaced by multifunctional long-burning boilers. In regions where main gas is available for heating, efficient gas equipment is used. In places not accessible to gas pipelines, more and more actively used.

Mankind understands that burning non-renewable energy sources is not a promising business, resources are gradually depleted. Scientists never stop looking new ways of extracting thermal energyand develop modern mechanisms for the implementation of the tasks.

In one of these projects, a heat pump was designed. Indeed, like most generating heat units, the operation of the heat pump is not possible without electrical energy. A serious difference is that electricity is not involved in heating, for example, a heating element, as in an oil radiator, and does not close the spiral in a heat gun. There are no heating elements in the heat pump, it does not create thermal energy, the heat pump serves only as a carrier of it from the environment to the consumer (coolant).

The electricity consumed by the heat pump is spent only on compressing the refrigerant and pumping it circulating. The refrigerant acts as a necessary working environment, it is he who moves heat from the environment to the heating system and hot water supply system. How to choose a heat pump, the principle of its operation, as well as learn about the pros and cons of such equipment, this review will help us.

Heat pump for heating

Traditional heating of a private house is still preferred if inexpensive resources are plentiful. The question is what to do when the availability of cheap sources is limited? An alternative solution is a heat pump - more than 40 years of experience in the European Union tells us that this can be very effective.

In the Russian Federation, the heat pump has not received proper distribution. The reason for this is two factors. First, there is an abundance of oil, gas, timber. Secondly, the high price and the lack of popularization stop it. Information about heat pumps is very scarce, the principle of their operation is not clear, and there is not enough information about the benefits.

In the European Union, the prices of fuel burned are so high that a geothermal heating system shows a benefit in operation. For example, up to 95% of households Sweden and Norway useheat pumps as the main source of heating. The International Energy Agency predicts that by 2020 heat pumps will begin to provide 10% of energy demand for heating in the countries of the Organization for Economic Cooperation and Development, and by 2050 this figure will reach 30%.

Heat pump for heating - principle of operation

From a school physics course, recalling the second law of thermodynamics, it is known for certain that heat from a hot body is transferred to a cold one without any mechanisms whatsoever. The trick is how to transfer heat in the opposite direction? To do this, we need a number of actions that provide the result.

It is these actions that the heat pump will help us to accomplish. The cost of electricity for the operation of a heat pump proportionally depends on the temperature difference between the media involved in this process.

Have you ever touched the black grill on the back of a refrigerator? Anyone can make sure that the back wall is very hot. By pointing a laser pyrometer at the black grating, it can be seen that its surface temperature is about 40°C. In this way, refrigeration equipment engineers utilize unnecessary heat from inside the freezer.

It is known that in the late forties of the last century, the inventor Robert Weber drew attention to the useless heating of the air with a refrigerator radiator. The inventor thought and connected an indirect heating boiler to it. As a result, Robert supplied the household with hot water in the required volume. It was then that the enthusiast thought about how to “turn” the refrigerator inside out and transform the cooling device into a heating device. You have to admit, he did it.

How does a heat pump work?

The principle of operation of the heat pump is based on the fact that underground at any time of the year, having fallen below the freezing level, we will stumble upon a temperature above zero. It turns out that the unfrozen ground layer is right under our feet. But what if you use it as the back wall of the freezer?

Applying the principle of operation of refrigeration equipment, to transfer heat from the underground to the home space, a system of pipes is used through which the refrigerant is circulated. Freon freons are heated by underground heat and begin to evaporate. The cold air outside cools it down, causing the freon to condense.

By heating the heat by alternating cycles of evaporation and heating, the heat pump circulates the refrigerant. The compressor creates pressure, forcing freon to move through the tubes of two heat exchangers.

In the first heat exchanger, freon evaporates at low pressure, during which heat is absorbed from the atmosphere of the immediate environment. The same refrigerant is then compressed by a high pressure compressor and moved to a second coil where it condenses. It then releases the heat absorbed earlier in the cycle.

The step-up compressor plays the main role in the process. By increasing the pressure, freon condenses and gives out more heat than it received from the warm earth. Thus, ground positive values ​​of + 7°С andis transformed into comfortable home conditions + 24°С.

Using a heat pump for heating, we obtain high efficiency.

I would like to note that the whole structure does not require a dedicated electrical wiring line. The power consumption is comparable to the energy consumption of a household electric kettle. The trick is that the heat pump “produces” four times more heat energy than it consumes electricity. No more than 3 kW will be spent on heating a cottage of 300 m2, in severe - 30 ° C frost.

However, the owner of a geothermal pump will have to fork out significantly in the beginning. The cost of equipment and materials for connection is at least $4,500. Add installation work and drilling, the same amount, it turns out that the simplest system will cost 10 thousand dollars.

It is clear that it will cost an order of magnitude cheaper. But pay monthly at the rate of 1 kW per 10 m2will have to anyway. So it turns out that for 300 sq. meters of the house will take 30 kW - 10 times more than will be spent on a heat pump.

Calculations for heating with gas using a gas boiler give approximately the same order of numbers - 2000 rubles per month, which is comparable to the operation of a heat pump. Unfortunately, not everyone lives in a gasified area.

The heat pump has an undeniable advantage. Such a “reverse freezer” in the summer can be “turned inside out” and with a slight movement of the hand - the heat pump turns into an air conditioner. On the street on hot days + 30 ° C, and coolness reigns in the dungeon. Using tubes filled with coolant, the pump will transfer the cold of the underground to the dwelling. Further, the fan is turned on, so we get an economical cooling system.

Operating practice indicates a payback period of 3 to 7 years. The Scandinavian countries have long calculated the profit and are heated by this method. A striking example is the giant heat pump in Stockholm, geothermal equipment. The source of thermal energy in winter and coolness in summer are the waters of the Baltic Sea. The slogan “Pay now, save later” applies to the heat pump! Savings are becoming more and more, due to the fact that energy carriers are becoming more expensive.

Heat pump. The truth about its effectiveness.

Unfortunately, not everything is so rosy with efficiency today. One of the main questions tormenting the consumer remains: to buy or not to buy a heat pump. Our advice, carefully weigh the pros and cons, most likely the option of buying a conventional one according to the results of operation will be cheaper, and installation is easier.

If we consider the heat pump as a concept of the future, as a new idea for generating heat, then the engineering idea definitely deserves respect. Geothermal equipment works, you can touch it with your hands, every year it becomes more efficient. However, if we calculate how much money we will spend on its operation, add the initial purchase and installation costs, we will most likely get an amount showing that we will spend much more money on it than on any other type of heat generating device.

Considering a heat pump as an economic system, when you spend 100 rubles on its operation, you get thermal energy for 300 rubles, do not forget that you paid a lot of money for the right to receive an excess profit of 200 rubles. By the way, in the same European Union, sales of heat pumps are supported by government programs.

So in Finland, more than 60 thousand heat pumps are sold annually and the number of sales is growing at a rate of 5%. But firstly, the economic effect of using such equipment is higher there due to expensive electricity. The cost of electricity in Finland is 35 euro cents, in comparison with Russia - 7 euro cents. Secondly, the subsidy program provides for reimbursement for the purchase of a heat pump in the amount of 3,000 EURO.

As long as low prices for gas and electricity exist, the introduction of a heat pump as a main competitor remains a difficult task. Mass consumption will become possible only in the event of a crisis with hydrocarbon production or a crisis with electricity generation.

How to choose the right heat pump

First stage.

Calculation of the required heat for home heating. To select a heat pump (HP), which is included in the heating system of the house, it is important to calculate the heat demand. An accurate calculation will help avoid unnecessary cost overruns, as this leads to unnecessary costs.

Second phase.

Which heat source to choose for your heat pump. This decision depends on many components, the main ones are:

  • financial component. This includes the direct cost of the equipment itself, as well as the installation of a geothermal probe or laying an underground thermal circuit. It depends on the location of the site itself, as well as on the immediate environment (reservoirs, buildings, communications) and geology.
  • operational component. The main part of the costs is the operation of the heat pump. This figure depends on the heating mode of your building and on the selected heat source.

Third stage.

Analysis of the initial data for the selection of a heat pump:

  1. Budget for the proposed system.
  2. Heating system: radiators, air heating, underfloor heating.
  3. The area of ​​the site that can be allocated for laying a thermal collector.
  4. Is it possible to drill on the site.
  5. Geology of the site to determine the depth of the geothermal probe, if such a decision is made.
  6. Is air conditioning required in the summer.
  7. Is there air heating or is it planned in the future.
  8. Capital cost of purchase and installation of HP with all work (approximate initial estimate).

Let's take everything in order

Budget for the proposed system

When creating a heating system on a HP, it is possible to install an air-to-water circuit. Capital investments will be minimal, since no expensive earthworks are required. But there will be high costs at the stage of operation of this heating system due to low efficiency.

If you want to significantly reduce operating costs, then installing a geothermal pump will suit you. True, it will be necessary to carry out earthworks for laying the thermal circuit. Also, this system will allow you to get "passive" cold.

Heating system: radiators, air heating, floor heating

To increase the efficiency of the HP system, it is desirable to reduce the difference between the temperature of the heated medium and the temperature of the heat source.
If you have not yet chosen a heating system, it is recommended to choose underfloor heating that allows you to use the heat pump system more efficiently.

The area of ​​the site that can be allocated for laying a heat collector

The area of ​​the site for installation of the collector is critical in case of impossibility of drilling and installation of a geothermal probe. Then you will have to lay the collector horizontally, and this will require space about 2 times more than the area of ​​\u200b\u200bthe heated house. At the same time, it should be taken into account that this area cannot be used for buildings, but only in the form of a lawn or lawn, so as not to block the flow of sunlight.

Is it possible to drill on the site

If it is possible to drill on the site (good geology, accessibility, lack of underground utilities), the best solution would be to install a geothermal probe. It provides a stable and long-term heat source.

Geology of the site for determining the depth of the geothermal probe, if such a decision is made

After calculating the total drilling depth, it is necessary to study the site plan and determine how to ensure the drilling depth. In practice, the depth of one well usually does not exceed 150 m.

Therefore, if, for example, the estimated drilling depth is 360 m, then, based on the characteristics of the site, it can be divided into 4 wells of 90 m, or 3 of 120 m, or 6 of 60 m. But it must be taken into account that the distance between the nearest wells should not be less than 6 m.
The cost of drilling is directly proportional to the depth of drilling.

Is air conditioning required in the summer

If air conditioning is required in the summer, then the choice of a water-to-water or ground-to-water heat pump is obvious, other heat pumps are not ready to effectively and economically perform air conditioning functions.

Is air heating available or is it planned in the future

It is possible to integrate HP into a single air heating system. This solution will unify engineering networks.

Capital cost of purchase and installation of a heat pump with all work

The approximate initial estimate of capital costs* for purchase and installation depends on the type of heat pump:

HP with underground collector:

Works - 2500 $
Operating costs - $350/year

HP with probe:
Equipment and materials - 4500 $
Works - 4500 $
Operating costs - 320 $ / year

Air HP:
Equipment and materials - $6500
Works - $400
Operating costs - 480 $ / year

HP "water-water":
Equipment and materials - 4500 $
Works - 3500 $
Operating costs - 280 $ / year

* - approximate, average market prices. The final cost depends on the selected equipment manufacturer, the region of work performed, the cost of drilling and site conditions, and so on. Note of the budget department

Fourth stage. Types of work

Single. The heat pump is the only source of heat, providing 100% of the heat demand. Works for working temperatures not higher than 55 °C.
Paired. The HP and the boiler work together, which allows the boiler to achieve higher operating temperatures.

Monoenergetic. HP and electric boiler form a power system with only one external source of energy. This allows you to smoothly regulate power consumption, but increases the load on the introductory machine.

Selecting a heat pump

After collecting all the initial data and working out the main technical solutions, it is possible to choose the appropriate type of HP. The configuration and choice of equipment supplier will depend on your financial capabilities. The main thing is to approach the choice of a system with a full understanding of what you want. We will help you choose and implement a comfortable heating system. It can take into account all the nuances: from the climate control function to the distribution of heat in the zones of the house.

Conclusion

Having opted for an ecological heating system with a heat pump, you can be confident in the future. You get complete independence from heat supply organizations, world oil prices and the political situation in the country. The only thing you need is electricity. But over time, the production of electricity can be transferred to absolute autonomy with the help of a windmill.

The first variants of heat pumps could only partially meet the needs for thermal energy. Modern varieties are more efficient and can be used for heating systems. That is why many homeowners are trying to mount a heat pump with their own hands.

We will tell you how to choose the best option for a heat pump, taking into account the geo-data of the site where it is planned to be installed. The article proposed for consideration describes in detail the principle of operation of systems for the use of "green energy", lists the differences. With our advice, you will no doubt end up with an efficient type.

For independent craftsmen, we present the heat pump assembly technology. The information presented for consideration is supplemented by visual diagrams, a selection of photos and a detailed video briefing in two parts.

The term heat pump refers to a set of specific equipment. The main function of this equipment is the collection of thermal energy and its transportation to the consumer. The source of such energy can be any body or medium with a temperature of +1º and more degrees.

There are more than enough sources of low-temperature heat in our environment. These are industrial waste from enterprises, thermal and nuclear power plants, sewage, etc. For the operation of heat pumps in the field of home heating, three independently recovering natural sources are needed - air, water, earth.

Heat pumps “draw” energy from processes that regularly occur in the environment. The flow of processes never stops, therefore the sources are recognized as inexhaustible according to human criteria.

The three listed potential energy suppliers are directly related to the energy of the sun, which, by heating, sets the air and wind in motion and transfers thermal energy to the earth. It is the choice of source that is the main criterion according to which heat pump systems are classified.

The principle of operation of heat pumps is based on the ability of bodies or media to transfer thermal energy to another body or medium. Recipients and suppliers of energy in heat pump systems usually work in pairs.

So there are the following types of heat pumps:

  • Air is water.
  • Earth is water.
  • Water is air.
  • Water is water.
  • Earth is air.
  • Water - water
  • Air is air.

In this case, the first word defines the type of medium from which the system takes low-temperature heat. The second indicates the type of carrier to which this thermal energy is transferred. So, in heat pumps water is water, heat is taken from the aquatic environment and liquid is used as a heat carrier.