How difficult is it to optimize energy consumption for heating? Indeed, in the end, it is its consumption that determines the total efficiency of the entire system. To do this, you need to know the correct costs for heating the house with electricity and gas, the calculation largely depends on the degree of insulation of the house.
Calculation of heat loss at home
What is the peculiarity of any heating system? Her work is designed to maintain a comfortable temperature in the room by compensating for the heat loss of the building. It is they who will largely determine the future costs of heating a country house.
To calculate this parameter, you need to know the value of the heat transfer coefficient R (m² * C / W) for each type of material the building is made of. It is the inverse of thermal conductivity. λ- W / m * S. It is calculated by the following formula, where d - wall thickness:
R = d / λ
The value of thermal conductivity of building materials can be taken from the data of the figure.
Such a technique is based precisely on these data and gives an answer to the question: what are the costs of heating a frame house in the future during its operation. It is important to consider all types of materials: load-bearing walls, window structures and thermal insulation.
The next step is to calculate the area of the external walls and windows. Suppose that in a house of 160 m² built of double-row brick and with an external layer of thermal insulation of 100 mm polystyrene, the total wall area is 360 m². The remaining 103 m² is occupied by window structures with R = 1.2. In this case, the average heat loss per 1 m² with a decrease in temperature by 1 ° C will be:
- 1 / (0.47 + 1.86) = 0.43 W / m² * C - for walls;
- 1 / 1.2 = 0.83 W / m² * C - for windows.
Based on this, it will be possible to find out what costs for heating with an electric boiler are necessary to obtain the optimal amount of thermal energy. For this, we take as a basis the value of the optimal temperature in the room + 25 ° C, and on the street - 15 ° C. The difference between them will be 40 ° C. In this case, the total heat loss at home will be equal to:
0.43 * 320 * 40 + 0.83 * 106 * 40 = 5504 + 3519 = 9023 W or 9.023 kW / h
By the same principle, heat losses through the attic and floor are calculated. In this case, they will be approximately equal to 3.92 kW / h for the floor and 1.83 kW / h for the attic. The total value for the entire building will be:
9.023 + 3.92 + 1.83 = 14.773 kW / h
A correction factor must be added to the resulting figure. It is due to the fact that the cost of heating with electricity or gas will increase during the opening of entrance doors, ventilation, etc. It is best to multiply the heat loss value by 1.1. Thus, it is possible to increase the power reserve of the heating system to 14.773 * 1.1 = 16 kW / h.
To accurately calculate the cost of gas or electric heating, you can calculate the heat loss using online calculators. It is necessary to choose those versions that take into account not only the parameters of the walls, but also the floor with the ceiling.
Calculation of costs for an electric boiler
The most expensive form of energy is electricity. Therefore, the calculation of heating costs for boilers of this type requires a balanced and accurate approach. Having chosen the optimal power of the equipment, it is necessary to correctly distribute it across all rooms. Ideally, the calculation of heat loss is recommended for each room. In this case, the accuracy of the calculations is significantly increased.
A correct calculation of the cost of electricity for heating should be carried out taking into account the following factors:
- Different types of tariff accounting. Currently there are 3 of them: one, two and multi-tariff;
- Installed thermostats on radiators connected to temperature sensors;
- Possibility of manual and automatic adjustment of boiler power.
As can be seen from the table, to minimize the cost of heating a country house, it is best to activate the system at night. However, in fact, to maintain a comfortable temperature, it should work during the day. In addition, you need to install a two-tariff meter, which is associated with certain difficulties - high cost, paperwork during registration.
The optimal distribution of the heating system is as follows:
- From 60% to 80% - night operation;
- FROM 20% to 40% - daily.
Such a scheme is relevant if there are no residents in the house during the day. The system’s operating time is 16 hours a day, which is enough to maintain a comfortable temperature. We take into account that a boiler with a thermal power of 16 kW and an actual consumed 16.7 kW was selected. This indicator directly depends on the efficiency. Then, the estimated costs of electric heating for the calculated house will be:
16.7 * 1.63 * 16 * 0.7 + 16.7 * 4.79 * 16 * 0.3 = 437 + 383 = 820 rubles per day
Given the ever-increasing tariffs for electricity, saving methods must be considered. For example, most of the cost of heating a frame house will be reduced due to good wall insulation and the use of wood as the main building material. An important factor is the availability of an auxiliary system. These include solar panels that generate electricity from windmills or a geothermal heating line. In this case, most of the cost of heating with an electric boiler will be offset by autonomous heat sources.
The electrical wiring in the house must withstand the maximum power of all electrical equipment, including the boiler. Before choosing a specific model, it is necessary to check the cross-section of the wiring and, if necessary, replace it with a more reliable one.
Calculation of gas heating costs
It is much more efficient to use natural or liquefied gas as an energy carrier - its cost will be cheaper. However, in addition to current expenses, high upfront costs must be considered. The correct calculation of the costs of gas heating should include the following articles:
- Registration of permits, purchase of equipment and preparation for its installation;
- Volume of gas consumed, balloon delivery or filling of a gas tank for liquefied.
The calculation of the costs of the first paragraph is purely individual in nature. After calculating them, you need to add the amount received to the calculation of gas heating costs. Usually it is distributed over several years. Thus, it is possible to obtain a relatively accurate amount including current upfront costs.
Trunk gas
In contrast to the calculation of the cost of electricity for heating, in addition to gas consumption, it is necessary to take into account the features of the boiler. All modern models must be connected to the mains. And although the consumption of electric power will be small, when analyzing seasonal costs, it will occupy a certain part.
After calculating the heat loss, we chose the boiler with a capacity of 16 kW. For modern models, the consumption of natural gas at the maximum operating mode will be about 1.72 m³ / h (Navien Turbo). Given the average tariff of 4.68 rubles / m³, you can calculate the cost of heating during the day:
1.72 * 16 * 4.68 = 128 rubles
As you can see, this figure is much less than when planning the cost of heating with electricity. In this case, the maximum power of the boiler during the entire period of operation was taken into account. For this boiler, the electric power consumption is 150 W / h. Those. total consumption will be equal to:
128 + 0.15 * 1.63 * 16 * 0.7 + 0.15 * 4.79 * 16 * 0.3 = 128 + 3.9 + 3.44 = 135 rubles
To reduce heating costs with an electric boiler, you can install a hybrid system. It will include an electric boiler of low power and a gas plant operating on liquefied fuel.
It is not recommended to purchase boilers with a large power reserve. They will have increased gas consumption, which will ultimately affect costs.
LPG
The calculation procedure for liquefied gas (propane-butane) is more complicated. This is due to uneven pressure in the cylinders or gas tank. To correct the actual costs of heating a country house, it is recommended to install an intermediate pumping station - a gas generator. It will maintain an optimal level of pressure in the line.
For such a scheme, two calculation methods can be used. The simple one is that it takes about 0.12 L to generate 1 kW of thermal energy. (0.00012 m³) of gas. For a boiler with a capacity of 16 kW at 16 hours daily operation, the consumption at a cost of 19 rubles / liter will be:
16 * 0.12 * 16 * 19 = 583 rubles
This value is for maximum boiler operation. If we resort to the method of accounting for heat losses, then the estimated amount of gas heating costs will be at a rate of 1.43 kg / h (Navien Turbo boiler):
1.43 * 18 * 19 = 489 rubles
As you can see, given the characteristics of the boiler, you can get a more accurate amount of flow. That is why when calculating the cost of heating a brick or frame house, you should familiarize yourself with the technical characteristics of the equipment.
Installing a gas tank at the equipment purchase stage is much more expensive than balloon heating. But it is much more convenient during operation.
Calculation of costs for district heating
Is it possible to save on costs when connecting to a central overdrive? The best way is to install heat meters, installing bypasses and temperature controllers. However, for vertical piping, this task is difficult, since in one apartment there can be from 2 to 5 risers. And for each you need to install a counter. The way out of this situation is the distributors of heating costs.
It is installed in front of the distribution heating unit in an apartment building. Moreover, in each apartment additional temperature sensors are mounted, signaling the degree of heating in the rooms. The installation of heating cost allocators has the following advantages:
- Automatic adjustment of the coolant supply volume depending on the outdoor temperature;
- The ability to set the volume of hot water supply by residents of the house. But this must be agreed with the management company.
It is important that the device of the distributor of heating costs and its operation do not contradict the legislation - Decree of the Government of the Russian Federation of November 18, 2013 No. 1034. This should be controlled by the management company that provides heat supply to the house.
Only licensed companies can install heating cost allocators. This issue must be agreed with the management company, which issues the technical conditions and controls the entire process.
What else needs to be considered when planning the costs of heating a house with electricity and gas? The calculation largely depends on the control devices and adjust the flow of coolant. Therefore, it is necessary to provide for the installation of temperature controllers, temperature sensors connected to the boiler in the system.
The video shows several practical recommendations for reducing heating costs:
