On set necessary for operation of the private house of engineering systems each project turns out individual even if standard architectural decisions are applied. Depending on a concrete situation, it is necessary to speak about various admissible capacity of power supply networks, about availability or inaccessibility of the main gas, etc. Thus, the main thought which it is necessary to inform to the customer, is that there are no "standard" estimates for costs of installation and operation of system of heating by which it would be possible to be guided, speaking about high cost or low cost of technologies. Instead the choice should be based on calculations for this concrete situation.
Heating — one of the most powerful items of expenditure on service of the private house. Therefore it is important not only the decision price, but also the subsequent expenses: cost of fuel, planned repairs, replacements of the served equipment, etc. Let’s compare by these criteria the most widespread options of systems of heating.
Than to heat
Available main gas
If the house is under construction on a site, to which communications are already brought (in particular, the main gas), house owners usually do not puzzle over a problem of a choice of fuel. Gas coppers are rather inexpensive — units of small capacity cost about 2,1 thousand roubles for 1 kW of capacity — and are rather effective (efficiency of coppers on the main gas — about 92 %). Besides, the gas equipment is convenient from the point of view of operation — fuel moves automatically, so, the house owner should not watch burning process constantly.
According to calculations, at gas cost in 4,24 rub/m3 (for the central regions of Russia) 1 and average term of operation of a copper in 10 years the general costs of house heating in the area 150 sq.m in 50 years in the prices of today will make about 2,2 million rubles.
Nevertheless, in our country the large quantity of settlements where the main gas represents "luxury" still remains. And in those settlements where the gas pipeline passes nearby, connection cost «to a pipe» sometimes exceeds all ideas of the reasonable.
Today among the alternative options of fuel most available to the average house owner it is possible to specify: the liquefied gas (downloaded in a gas-holder), diesel fuel, coal, an electricity and firewood. Besides, the segment of thermal pumps at which while many look cautiously because of big initial investments actively develops.
Possibility of installation of a gas-holder essentially depends on features of the region, to be exact — from availability of the liquefied gas with delivery to a site. At first sight, such decision can seem much more economically than connection to the main gas pipeline. Coppers for the liquefied gas possess high efficiency at the same average cost, as a copper discussed above and installation of a gas-holder is not too expensive to the main gas. However the pleasure it all the same turns out not from cheap because of high cost of delivery of fuel, especially in the distance from the large cities.
At cost of the liquefied gas in 13,5 rubles for литр2 (with delivery within 100 km from the large city) and term of operation of a copper and a gas-holder in 10 and 50 years respectively the general costs of heating in 50 years in the prices of today will make about 3,75 million rubles.
Diesel fuel in regions is usually simpler for getting, rather than the liquefied gas with delivery to a site. Besides, it can be brought from wholesale base independently. However, transportation costs in this case too should be put in cost of operation of system of heating. The diesel engine has also a number of shortcomings. First, the copper has smaller efficiency, secondly, demands more large-scale works on installation (and installation should be made in a separate room). Besides, the diesel copper is dependent on the electric power: at frequent shutdown of light it is necessary to take care of generator purchase.
As a result at diesel fuel cost with delivery to a place in 28,6 rbl/l in 50 years in the prices of today "runs" about 8,35 million rubles: a diesel engine — the most expensive decision for heating.
Firm fuel: coal and firewood
Firm fuel differs from described above options that it considerably complicates operation of system of heating. When using the elementary equipment the house owner should watch continuously process of burning or to reflect on quite expensive system of automatic supply of fuel (by the way, not intended for work with simple firewood). There are also various improved versions of the coppers, allowing to increase the period between a laying of fuel. However such decisions essentially more expensively. Here we will be limited to option with use of "classical" solid-state coppers with service life to 20 years, firewood (cost of 1,5 thousand rub/m3) or coal (cost from 6,3 thousand rub/t).
Their application in 50 years will manage in 2,6 and 3 million rubles according to, without possible automation of system of heating (at installation of system of automatic supply of coal primary expenses on the equipment will be more, but system operation considerably will become simpler).
It should be noted also that for the coppers working at firewood, the question of storage of fuel is also actual, after all at increase of humidity of wood with 20 to 50 % its specific warmth of combustion falls in 2 times. At this efficiency of solid-state coppers and so it is not high — to 80 % (more often — 75 %).
Heating at the expense of an electricity not to well many house owners because of limited maximum capacity of connection of a house to the power supply network. Besides, in many regions the problem of frequent blackouts is actual. At the expense of the household reserve generator an electric copper not to "support".
Equipment service life — however, an electric copper thus does not demand 5 years difficult installation works or regular service. The general expenses at cost of the electric power of 2,81 rub / кВт*ч (on an example of the Moscow region) 4 in 50 years will make 6,4 million rubles.
Thermal pumps rather appeared recently in the Russian market. As well as on heating on the basis of an electricity, house owners look at them with scepticism, assuming that in the conditions of unstable supply of electricity such decision will not rescue in the winter. However, unlike mentioned above an electric copper (to which 15 kW are necessary), much more the smaller capacity in this case is necessary. For example, for (to 18 kW of heating capacity) it is required the pump of high efficiency of Danfoss DHP-S only 4,9 kW of the electric power, i.e. already quite will be suitable for reservation of this system a usual household diesel engine generator.
The thermal pump — is harmless alternative to firm fuel or an expensive gas-holder in conditions when the main gas is not available to the consumer. And this technology successfully works even in northern regions where the earth during the winter manages to be chilled deeply (that proves to be true long-term operating experience of similar systems in Scandinavia).« There is a stereotype that thermal pumps yield optimum result only in rather warm Europe. But modern units allow to use them in any Russian region. In the south soil collectors on depth of 1-1,5 meters are usually established or heat of air is used. In regions where depth of a promerzaniye is lower, it is possible to place soil probes in wells to 200 meters or to use thermal energy of nonfreezing reservoirs and ground waters» — Andrey Osipov, the area manager «Thermal pumps» tells the Danfoss companies, leading global manufacturer of the energy saving equipment.
Term of operation of the thermal pump — more than 25 years. Its cost is rather great, at the same time costs of heat exchanger arrangement (drilling, etc.) at replacement of the equipment be not required. About 100 years and more are capable to serve qualitative geothermal probes. Besides, thermal pumps do not need expensive regular service.
The general costs of heating within 50 years (taking into account initial cost of the equipment and ground works) will make about 3,3 million rubles in the prices of today.
Thus, the thermal pump counting on 50 years of operation of a house appears more economically, rather than use of the liquefied gas (in a gas-holder), in 2 times is more favorable than electric heating and almost in 3 times is more favorable than heating by diesel fuel. Naturally, payback period of such decision much less.
To told it is necessary to add that the thermal pump in summertime is capable to carry out successfully conditioner function so house owners can save on its purchase. Thus unit power consumption in a mode of passive cooling is comparable to power consumption of a bulb of an incandescence.
It should be noted also that the calculation given above could be corrected still (that would complicate, however, comparison of technologies): on the one hand, the principle of the thermal pump means possibility of use of the equipment with smaller capacity of heating. With another to make system of more effective installation in the house of liquid heat-insulated floors, instead of standard radiators (the efficiency of the thermal pump is maximum at a small difference of temperatures of the heat-carrier on an entrance and an exit) allows.
Correction of figures in favor of the house owner
In estimated calculations usually a certain standard house of the average area undertakes a starting point with the same average equipment. Thus details concerning distributing of pipes of the heating, applied radiators and comfortable temperature which is preferred by residents are not specified. All these individual parameters, but they allow at the expense of additional investments at an installation stage as a result essentially to cut down expenses on operation of heating system.
«Unlike an apartment house where the reached economy not always is reflected in the account for heating, in the private house each not spent gigacalorie of heat — is a notable prize in money. Lower heat expense — is required gas or diesel fuel on a heating season less. Differently, all measures of economy give direct financial effect» — Yury Marinin, the project manager on a cottage segment of the Danfoss company speaks.
The first what it is necessary to mention — is radiatorny temperature regulators. The problem of these devices — to provide optimum consumption of heat, without allowing an overheat of rooms. Today in the market there are three types of mechanical radiatorny thermostats: with wax, liquid and gas filling of a thermosensitive element. Wax, though cost cheaper in the construction markets of everything, are the most inertial. Similar devices very slowly — in 40-60 minutes — react to temperature changes indoors, so, allow the fluctuations of temperature affecting the general consumption of heat. Liquid devices work quicker: they need about 25 minutes.
«Speed of reaction of the thermostat on change of surrounding conditions plays a key role for economy and comfort. Therefore, besides liquid, "Danfoss" lets out devices with gas filling of the RA series. The device is created on the patented technology and has no analogs in the market. It reacts to temperature change in only 8 minutes and provides notable savings of thermal energy. One more new development — the intellectual electronic Living Eco device. Besides exact maintenance of temperature in a room, such thermostat can be arranged under sharp changes in a condition of Wednesday, for example, to fix the airing beginning (sharp fall of temperature in a room). Not to warm the street, the device stops heat-carrier giving in a radiator for that time while the window is open, providing additional economy. Temperature regulators with gas filling allow to save to 36 % of heat, electronic Living Eco thermostats — to 46 % * »— Yury Marinin explains.
One more way to correct house heatconsumption — to use in addition to radiatorny heating water heat-insulated floors. Unlike an apartment house where the electric heat-insulated floors more often are mounted, allowing to raise comfort of accommodation at the expense of additional expenses on an electricity, in the private house for water heat-insulated floors it is possible to use the same source of heat, as for heating radiators. Differently, additional expenses at an operational phase will not be, and there will be even a prize, speaking subjective perception the person of comfortable conditions.
«For us the most comfortable distribution of temperature — when feet in heat, and the head in cold. If the room is heated by means of a radiator, warm air concentrates from above, and at a floor the coldest zone is formed. To achieve comfort, the person establishes more high temperature in a room. The this temperature is higher, the it is more than loss through glasses, walls, etc. If heating of a room goes from a heat-insulated floor, that the warm zone appears below. Practice shows that for achievement of comfort in this case the person adjusts temperature in a room somewhere on the average on 1-2 degrees below. It leads to savings to 10 % of energy» — Yury Marinin speaks.
It should be noted that efficiency of an expenditure of energy can be operated heat-insulated floors. First, for decrease in heatlosses it is necessary to provide balancing of loops of a water floor. Usually the length of one pipe of the water floor laid in a coupler, does not exceed 100 m. At standard laying this pipe provides heating about 10-15 square meters of a floor. If one floor of an average individual cottage usually has the area about 100 square meters, for the organization of heating of all area of a floor it is required to lay 7-10 separate loops. It is obvious that each of them will differ a configuration, in the length, etc. If not to undertake additional measures, the floor will have different temperature on separate sites that will lead to the increased heatlosses because of subjective perception of comfort. Moving on the house, the person will periodically get on cold sites. Having felt discomfort in these areas, it will add temperature that will lead to an overheat of other zones and excessive loss of heat through protecting designs. To level temperature of separate sites of a floor the special devices compensating a difference of hydrodynamic resistance of contours at a stage of control, for example, ventilny inserts with precontrol, Danfoss of the FHF series established in collectors allow.
But even after balancing there is a need to regulate temperature in each room separately. It is defined by house service conditions: the sun during the day moves, heating up that one party, another. People on rooms are differently distributed. As a result inflow of heat to each room will change over time, so, it is necessary to correct and thermal capacity of a floor (by analogy to temperature maintenance by means of the radiatorny thermostat).
«For adjustment of temperature of a floor we recommend to use room thermostats of the TP5001 series with the temperature sensors established in a coupler. Being connected with a collector, such device will stop heat-carrier giving in a separate loop of a heat-insulated floor if for any reasons it is required to reduce heating capacity.
By the way, these devices provide a so-called hrono-proportional operating mode of floors. A cement coupler — quite inertial thing from the point of view of temperature changes. If since morning a room started to heat up continuously by means of a heat-insulated floor, and then there was a sun, the device in a coupler will react when indoors will be already too hot. To provide more uniform temperature, the room thermostat of the TP5001 series includes heat-carrier giving in a floor several times at an o’clock (periodicity of inclusions is adjusted) during a small period. Such operating mode allows to maintain temperature much more precisely, in comparison with traditional room thermostats» — Yury Marinin tells. Application mentioned above decisions promotes reduction of expenses for operation of system of heating, so, will help to make more realized choice for this or that heating decision.
One more moment to which it is necessary to pay attention — is a choice of the scheme of the organization of circulation of the heat-carrier on pipes: natural (gravitational) or compulsory. Certainly, the compulsory scheme of circulation of the heat-carrier will increase costs of installation and operation of system of heating: pump installation, its connection to the electric power is required. But the gravitational scheme has a set of shortcomings on which house owners often and do not reflect. First, for its installation it is necessary to use pipes of bigger diameter, thus to mount them under a certain corner. It means that expenses on purchase of the equipment and initial installation increase. Besides, pressure in system is not so high to use gravitational schemes at the big areas of the house across (at length of pipes more than 30 meters) 5. Economic reasons, along with convenience of use, will help to explain advantages of the compulsory scheme even to nonspecialists.
Installation of the circulating pump allows application of various assembly decisions when distributing pipes. Along with automatic radiatorny temperature regulators and possibilities of flexible management of a copper operating mode, the pump allows to regulate work of system of heating that in inter-season period gives the chance to save fuel. Compulsory circulation is also necessary for installation of liquid heat-insulated floors.
The love of future owners of the budgetary housing to universal economy can be used for the qualified explanation of a choice of this or that technology of heating. Calculations of expenses for long-term operation allow to bring together both engineering vision, and aspiration to economy.