What is this unit - gigacalorie? How does it relate to the more familiar kilowatt-hours of thermal energy? What data is needed to calculate the heat received by the room in gigacalories? Finally, what formulas are used to calculate? Let's try to answer these questions.
What it is
Let's start with a related definition. A calorie is the amount of energy required to heat 1 gram of water by 1 degree Celsius at atmospheric pressure.
Since one calorie is a ridiculously small amount compared to the heat costs for heating rooms, calculations usually use a gigacalorie (Gcal), equal to one billion (10^9) calories.
The use of this particular value is provided for by the “Rules for accounting for thermal energy and coolant”, published by the Ministry of Fuel and Energy of the Russian Federation in 1995.
Reference: the average heat consumption standard in Russia is 0.0342 gigacalories per square meter of total housing area per month.
Standards for different regions vary depending on climate zone and are determined by local legislative bodies.
What is Gcal in heating in more familiar quantities?
- One gigacalorie is enough to heat 1000 tons of water by one degree.
- It corresponds to 1162.2222 kilowatt-hours.
Why is this necessary?
Apartment buildings
It's very simple: gigacalories are used in calculations for heat. Knowing how much thermal energy is left in the building, the consumer can be given a very specific bill. For comparison, when central heating operates without a meter, the bill is issued based on the area of the heated room.
The presence of a heat meter implies a horizontal series or collector: the outlets of the supply and return risers are installed in the apartment; the configuration of the indoor system is determined by the owner. This scheme is typical for new buildings and, among other things, allows you to flexibly regulate heat consumption, choosing between comfort and savings.
How is the adjustment carried out?
- Throttling the heating devices themselves. The throttle allows you to limit the flow of the radiator, reducing its temperature and, accordingly, heat consumption.
- By installing a common thermostat on the return pipe. The coolant flow will be determined by the temperature in the room: when the air is cooled, it will increase, when heated, it will decrease.
Private houses
The cottage owner is primarily interested in the price of a gigacalorie of heat obtained from various sources. We will allow ourselves to give approximate values for Novosibirsk region for tariffs and prices 2013.
For comparison: central heating at the time of collecting statistical data cost 1,467 rubles per gigacalorie.
Counters
What data is needed for heat accounting?
It's easy to guess:
- The flow rate of coolant passing through heating devices.
- Its temperature at the inlet and outlet of the corresponding section of the circuit.
Two types of meters are used to measure flow.
Meters with impeller
Meters intended for heating and hot water supply differ from those used for cold water only in the material of the impeller: it is more resistant to high temperatures.
The mechanism itself is the same:
- The coolant flow causes the impeller to rotate.
- It transmits rotation to the metering mechanism without direct interaction, through a permanent magnet.
Despite the simplicity of the design, the meters have a fairly low response threshold and are well protected from data tampering: any attempt to slow down the impeller with an external magnetic field will rest on the presence of an antimagnetic screen in the mechanism.
Meters with differential recorder
The device of the second type of meters is based on Bernoulli's law, which states that the static pressure in a flow of liquid or gas is inversely proportional to its speed.
How to use this feature of hydrodynamics to calculate coolant flow? It is enough to block his path with a retaining washer. The pressure drop across the washer will be directly proportional to the flow rate through it. By recording pressure with a pair of sensors, it is easy to calculate flow in real time.
It’s curious: the design of the meter implies the presence of electronics in it.
Most models of meters of this type provide not only raw data - water consumption and its temperature - but also calculate the actual use of heat.
The control module of such devices has a port for connecting to a computer and can be reconfigured with your own hands to suit the changed calculation scheme.
But what if we are not talking about a closed heating circuit, but about open system with the possibility of DHW selection? How to record an expense hot water?
The solution is obvious: in this case, retaining washers and pressure sensors are placed on both the feeder and the . The difference in coolant flow between the threads will indicate the amount of hot water that was used for household needs.
The photo shows an electronic heat meter with pressure drop recording on the washers.
Formulas
The calculation formula is Q=((V1*(T1-T))-(V2*(T2-T)))/1000.
In it:
- Q is the required amount of thermal energy in gigacalories.
- V1 and V2 - coolant flow through the supply and return in tons.
Useful: meters, for obvious reasons, show consumption in cubic meters, and not in tons.
The actual mass of a cubic meter of hot technical water is slightly different from one ton; but the difference against the background of the meter errors is negligible, so you can safely use the meter readings in cubic meters.
- T1 is the temperature at the entrance to the circuit (supply).
- T2 is the temperature at the outlet of the circuit (return).
- T - temperature cold water, feeding the route to compensate for losses. IN heating season it is taken equal to +5 C, out of season - +15 C.
- Dividing by 1000 is necessary precisely in order to get the result not in mega-calories, but in gigacalories. Otherwise, we would have to recalculate water consumption into thousands of tons.
So, with a meter flow rate of 52 m3 for supply, 44 m3 for return, supply temperatures of 95 C and return temperatures of 70 C, the house will remain ((52*(95-5))-(44*(70-5)))/ 1000=1.82 Gcal of heat.
Please note: water consumption is charged separately.
We only consider the consumption of thermal energy.
What do the calculation instructions look like if you have only one meter - on the feed? Of course, it is assumed that we are talking about a closed system (without DHW).
The calculation formula is Q=V*(T1-T)/1000.
For example, with a water consumption of 52 m3 and a coolant temperature of 95 C, 52 * (95-5) / 1000 = 4.68 gigacalories will remain in the apartment supply. As is easy to see, such a calculation system is much less beneficial to the consumer.
An intermediate solution for closed systems is one flow sensor and two temperature sensors. The calculation is performed using the first formula; V1 is taken equal to V2.
Conclusion
We hope that the information presented to the reader will help him save on heating. As always, additional thematic materials can be found in the attached video. Good luck!
Today, the main document defining the requirements for heat energy metering is the “Rules for heat energy and coolant metering”.
The Rules provide detailed formulas. Here I will simplify a little for better understanding.
I will only describe water systems, since they are the majority, and will not consider steam systems. If you understand the essence using the example of water systems, you can calculate the steam yourself without any problems.
To calculate thermal energy, you need to decide on your goals. We will count calories in the coolant for heating purposes or for hot water supply.
Calculation of Gcal in the DHW system
If you have a mechanical hot water meter (spinner) or are planning to install one, then everything is simple. How much you have charged, you will have to pay according to the approved tariff for hot water. The tariff, in this case, will already take into account the amount of Gcal in it.
If you have installed a thermal energy metering unit in hot water, or you are just going to install it, then you will have to pay separately for thermal energy(Gcal) and separately for network water. Also at approved tariffs (RUB/Gcal + RUB/ton)
To calculate the number of calories you get from hot water(as well as steam or condensate), the minimum that we need to know is the flow of hot water (steam, condensate) and its temperature.
Flow is measured by flow meters, temperature is measured by thermocouples, temperature sensors, and Gcal is calculated by a heat meter (or heat recorder).
Qgv = Ggv *(tgv - tkhv)/1000 = ... Gcal
Qgv - amount of thermal energy, in this formula in Gcal.*
Ggv - consumption of hot water (or steam, or condensate) in cubic meters. or in tons
tgv - temperature (enthalpy) of hot water in °C **
tхв - temperature (enthalpy) of cold water in °C ***
* divide by 1000 in order to get gigacalories rather than calories
** It is more correct to multiply not by the temperature difference (t heated - t cold), but by the difference enthalpy(h gv-h xv). The values of hgv, hhv are determined from the corresponding average values of temperatures and pressures measured at the metering station for the period under consideration. Enthalpy values are close to temperature values. At the thermal energy metering unit, the heat meter itself calculates both enthalpy and Gcal.
***cold water temperature, also known as make-up temperature, is measured on the cold water pipeline at the heat source. The consumer typically does not have the option to use this option. Therefore, a constant calculated approved value is taken: during the heating period tхв=+5 °С (or +8 °С), during the non-heating period tхв=+15 °С
If you have a turntable and there is no way to measure the temperature of hot water, then to allocate Gcal, as a rule, the heat supply organization sets a constant calculated value in accordance with regulatory documents and the technical capabilities of the heat source (boiler room, or heating point, For example). Each organization has its own, ours is 64.1°C.
Then the calculation will be as follows:
Qgv = Ggv * 64.1 / 1000 = ... Gcal
Remember that you will need to pay not only for Gcal, but also for network water. According to the formula, we only count Gcal.
Calculation of Gcal in water heating systems.
Let's consider the differences in calculating the amount of heat with an open and closed heating system.
Closed heating system- this is when it is prohibited to take coolant from the system, either for hot water supply or for washing a personal car. In practice, you know how. Hot water for DHW purposes in this case enters through a separate third pipe or there is none at all if DHW is not provided.
Open heating system- this is when it is allowed to take coolant from the system for hot water supply purposes.
With an open system, coolant can be taken from the system only within the framework of contractual relations!
If during hot water supply we take away all the coolant, i.e. all the network water and all the Gcal in it, then during heating we return some part of the coolant and, accordingly, some part of the Gcal back into the system. Accordingly, you need to calculate how many Gcal came in and how much went out.
The following formula is suitable for both an open and closed heating system.
Q = [ (G1 * (t1 - tхв)) - (G2 * (t2 - tхв)) ] / 1000 = ... Gcal
There are a couple more formulas that are used in accounting for thermal energy, but I take the higher one, because I think that it is easier to understand how heat meters work, and which give the same result in calculations as the formula.
Q = [ (G1 * (t1 - t2)) + (G1 - G2) * (t2-txv) ] / 1000 = ... Gcal
Q = [ (G2 * (t1 - t2)) + (G1 - G2) * (t1-tхв) ] / 1000 = ... Gcal
Q is the amount of thermal energy consumed, Gcal.
t1 - temperature (enthalpy) of the coolant in the supply pipeline, °C
tхв - temperature (enthalpy) of cold water, °С
G2 - coolant flow in the return pipeline, t (cub.m.)
t2 - temperature (enthalpy) of the coolant in the return pipeline, °C
The first part of the formula (G1 * (t1 - txw)) counts how many Gcal came in, the second part of the formula (G2 * (t2 - txw)) counts how much Gcal came out.
According to the formula [3] heat meter will count all Gcal one figure: for heating, for drawing hot water when the system is open, instrument errors, emergency leaks.
If at open system heating supply, it is necessary to allocate the number of Gcal used for hot water supply, then additional calculations may be required. It all depends on how the accounting is organized. Are there devices on the hot water pipe connected to the heat meter, or is there a turntable there?
If there are devices, then the heat meter itself should calculate everything and issue a report, provided that everything is configured correctly. If there is a turntable, then you can calculate the number of Gcal used for hot water supply using the formula. . Do not forget to subtract the Gcal used for hot water supply from the total amount of Gcal according to the meter.
A closed system means that the coolant is not taken from the system. Sometimes designers and installers of metering units mess with the project and program the heat meter with a different formula:
Q = G1 * (t1 - t2) / 1000 = ... Gcal
Qi is the amount of thermal energy consumed, Gcal.
G1 - coolant flow in the supply pipeline, t (cub.m.)
t1 - coolant temperature in the supply pipeline, °C
t2 - coolant temperature in the return pipeline, °C
If a leak occurs (accidental or intentional), then according to the formula, the heat meter will not record the amount of lost Gcal. This formula does not suit heat supply companies, at least ours.
Nevertheless, there are accounting units that work according to this calculation formula. I myself several times issued instructions to Consumers to reprogram the heat meter. Given that when the Consumer brings a report to the heat supply company, it is NOT visible what formula is used to calculate it, it is possible to calculate it, of course, but it is extremely difficult to calculate all Consumers manually.
By the way, of those heat meters for apartment-by-apartment heat metering that I have seen, not one provides for measuring the coolant flow in the forward and return pipelines simultaneously. Accordingly, it is impossible to calculate the amount of Gcal lost, for example in an accident, as well as the amount of coolant lost.
Conditional example:
Initial data:
Closed heating system. Winter.
heat energy - 885.52 rub. / Gcal
network water - 12.39 rub. / m.cub.
The heat meter issued the following report for the day:
Let’s say that the next day there was a leak, an accident, for example, 32 cubic meters leaked.
The heat meter issued the following daily report:
Calculation error.
With a closed heating system and no leaks, as a rule, the flow rate in the supply pipeline is greater than the flow rate in the return line. That is, the instruments show that one amount of coolant comes in and a little less comes out. This is considered the norm. In the heat consumption system there may be standard losses, a small percentage, small smudges, leaks, etc.
In addition, metering devices are imperfect; each device has a permissible error established by the manufacturer. Therefore, it happens that with a closed system one amount of coolant enters, but more comes out. This is also normal if the difference is within the permissible error.
(see Rules for metering thermal energy and coolant, clause 5.2. Requirements for metrological characteristics metering devices)
Error(%) = (G1-G2)/(G1+G2)*100
For example, if the error of one flow meter set by the manufacturer is ±1%, then the total permissible error is ±2%.
Heating system
Price utilities is constantly growing, and you have to pay for them every month. If everyone more or less understands the calculation of payment for water consumption and sewerage use, then the required payment for heating seems dubious to most consumers. Many residents are concerned about the question of why the amounts for the summer period differ from winter payments, and in a building located nearby, residents receive receipts with completely different figures. Surely this is worth looking into.
What determines the payment for supplied heat?
The heat energy consumption standard determines that residential premises must ensure and maintain a comfortable environment for humans. temperature regime. It is established by certain rules for the supply of utilities.
The standard is calculated in Gcal per 1 sq. meter of total area of a private building or apartment building. The following indicators are taken into account:
- The total consumption of heat energy required to heat the entire house during the heating season. It is determined using common house or individual meters heat.
- The total area of the heated house, taking into account the buildings connected to the heating system.
- The duration of the heating period, including partial calendar months during which the first indicator was measured.
The calculation also involves taking into account the average daily temperatures of indoor and outdoor air during those periods of the year when the houses have heating. In the first case, the values specified in the standards for the provision of utility services are taken as a basis. In the second - averaged data for the 5 previous heating seasons provided by the regional hydrometeorological service.
There is another important parameter of outdoor air - its average minimum temperature. Its calculation is based on measurements of the five coldest days of the winter season, located in a row.
IN middle lane In Russia, centralized heating of residential buildings is carried out within 7–8 months. This usually occurs from October to April or May. But in the first and last months, heat is supplied partially - before or after a certain date, as well as at a lower consumption standard. From November to March–April it remains stable.
The calculation procedure may vary:
- The tariff for heat energy is averaged, and the payment does not change throughout the year, despite the fact that there is no heating in the summer. In this case, the material burden on the consumer is distributed evenly.
- During the coldest time of the heating season, you have to pay the maximum, in the first and last months it is slightly less, and in the warm season the payment is minimal or completely absent.
How payments are approved
Standards and tariffs are calculated and compiled by heat supply organizations with the involvement of specialists. Then they are approved by energy commissions within a certain region, region or individual locality. The calculation of the expected payment is submitted to the territorial commission for consideration. Deputies of various levels and representatives of local executive authorities, including public organizations, are necessarily invited to its meeting.
Counters for control
Tariffs are calculated in accordance with government regulations that establish and define consumption standards for utilities, in particular for heating. Heat supply organizations must document and justify every penny, otherwise it will not be included in the final payment for heating.
Approved tariffs and heating payments remain unchanged until their next possible regulation, as well as determination of the cost of the supplied coolant, which depends on many components.
How is the payment generated?
Payments for supplied heat to consumers are made taking into account not the residential area, but the total area of the apartment or house. Consumption standard in Gcal/sq. m is multiplied by the tariff approved for each locality in rubles/Gcal. As a result, the cost of heating costs is determined, expressed in rubles/sq. m, which is again multiplied by the number of total square meters dwellings. This amount is what consumers see on their receipts.
In many localities, uniform rules have been adopted. But if a meter is installed in a high-rise building, the calculation is made individually. It may differ significantly from the accepted figure. The indicators of metering devices and the total occupied area of each apartment are important here. In this case, payment for heating will also include part of the cost of thermal energy for additional needs of the house, for example, heating stairwells, vestibules and basements.
Monitoring of thermal energy consumption
The actual outside air temperature during the heating season may be higher or lower than the average daily values that were taken into account when calculating the heat consumption standard. Taking into account this fact Once a year, utility services recalculate. In case of overpayment to homeowners, it is counted against future charges. And if in winter it was much frostier outside than determined by the standards, then consumers will have to pay an additional amount. Therefore, there is no need to panic if an incomprehensible number appears on the receipt - in housing offices you can always find out where it came from. This applies to houses without coolant temperature meters.
In multi-storey buildings with meters, the amount of heat consumed is influenced by many factors. Some owners install radiators with additional sections or simply increase the number of heating devices. Others insulate loggias and even install radiators on balconies. Someone is installing warm water floors throughout the apartment. All this increases the general house heating costs. As a result, it turns out that someone’s apartment is warmer, while others have to pay for someone else’s comfort out of their own pocket. After all, it is produced depending on the total area of the apartment, and not on the number of heating devices.
So what the best option To account for the consumption of thermal energy and your material assets, you will need to install an individual metering device, or meter.
Control of heat energy consumption
Meters installed in an apartment or private house allow you to control and strictly monitor the amount of heat energy actually spent on heating the premises. Therefore, consumers can save significantly on utility bills. This is especially clearly visible if control valves are installed on the radiators.
You can only pay for the heat received
It happens that in winter you have to open windows or transoms due to the fact that centralized services do not adjust the temperature of the coolant depending on the outside air temperature, and the radiators heat up more than required. Or vice versa - residents do not feel very comfortable in cold apartments in severe frost.
Consumers who do not have meters have no desire to save on utility bills for heating. Why additionally insulate windows or walls if the house is already warm?
Another thing is installation individual device metering with the ability to regulate the amount of incoming coolant. This measure encourages owners to be thrifty and thrifty. It will be in their interests to take appropriate measures to insulate enclosing structures and openings. And you won’t have to pay for your neighbor’s heating. The calculation is very simple - as much as you consumed, you paid as much.
To bet or not to bet?
The work of the heat meter is to measure and record the volume, pressure and temperature of the incoming coolant. Manufacturers produce two main models of household measuring instruments:
- tachometer - less accurate, but cheaper;
- ultrasonic - reliable, durable, characterized by measurement accuracy, but at the same time high price.
Of course, an individual measuring device has a lot of advantages, and after a while it will definitely pay for itself. But to think that everything will end with the allocation of material resources only for its acquisition is not entirely correct. It is prohibited to install heat meters on your own, therefore, the cost of installing a set of equipment must be included in the cost calculation, which can amount to 2 times more than the price of the meter itself.
The installation is carried out by specialized companies that have permits to carry out such work.
Installation of thermal energy meters
In addition, do not forget that the measuring device must be tested every 3-4 years, for which you will also have to pay a certain amount.
When choosing a heat meter, you need to pay attention to the presence of a technical passport and certificate, and after its installation - to the mandatory presence of a seal. The delivery package includes not only a measuring device, but also shut-off valves, located before and after it.
The meter will help to really save the family budget, since the consumer will only pay his own bills without taking into account the losses of utility companies. As a result, the services will have to put things in order heating network, begin to strictly control defects and provide quality services.
Who should I trust with the installation?
It is unacceptable to involve amateurs in the installation of heat consumption metering devices. Specialists of the profile company must provide:
Permits:
- certificates;
- tolerances;
- certificates, including state registration.
- An extract from the Unified State Register of Legal Entities containing information about the service provider company.
- Warranties and service options.
- Benefits for certain categories of citizens established by law.
- Installation plan, specifications and estimate.
- Possibilities and period of installment plans.
Possible way out of the situation
Radiator
For horizontal wiring heating pipes In a house or apartment, there are no problems when installing heat meters. They are compact in size and can be easily placed on straight sections of pipelines through which coolant flows. If necessary, measuring equipment can be installed on the return line.
But not in everyone apartment building It is possible to install an individual apartment heating meter. Old-built houses are equipped with vertical pipe distribution, so risers are located in every room. But it doesn’t make sense to install several meters in one apartment. This will result in a decent amount and is unlikely to live up to expectations.
But don't be discouraged. Manufacturers took care of such heating schemes and offered another option for heat energy metering - distributors. They measure the temperature difference on the surface of heating devices and the air in the room, on the basis of which the coolant flow rate is determined. The cost of distributors is 6–8 times less than heat meters, and the costs of their installation are much more modest.
Another solution is to install a house-wide energy consumption meter spent on heating. In this case, all apartment owners must give their written consent. The following are compiled:
- application to the attached housing office;
- request to district heating network services for the possibility of installing devices.
After a certain time:
- heating networks issue specifications;
- an agreement is concluded with a specialized enterprise for the installation of equipment;
- installation of devices and components, as well as shut-off, distribution and control valves is carried out.
What to do after installation?
Counting expenses
Owners of any home are obliged to treat heat metering devices with care. They answer:
- for the safety of equipment;
- routine check and replacement of the meter;
- correct readings and their transfer to heat supply services;
- timely payment of consumed heat energy;
- admission of representatives of heating networks to the meter to verify the readings provided by the consumer.
Usually, the documentation after installation of metering devices is carried out by the companies that installed them. But some consumers do this on their own, although going through the authorities takes a lot of time.
The standards provide for the commissioning of the meter no later than a month after its installation. And payment according to indications begins the next day after acceptance into operation.
Verification of the accuracy of meter readings is permitted if the consumer fails to provide them for more than three months. In this case, the heat supply organization must notify the owner about the possible time of arrival of its representative and the consequences of not allowing access to the meter.
Conclusion
Consumers often complain about unfair heating standards and tariffs. Today it is the largest in amount communal payment. Many people are not happy with the fact that their neighbors’ apartments are much warmer, and their heating receipts show the same numbers only because the total area is the same. And who is happy to pay for hot batteries when it’s already warm outside? There is a way out of this situation - installing a device responsible for metering thermal energy.
Thermal energy has several measurement options.
Energy power, which is measured in Watts (W, mW and kW), is most often indicated by heating boilers, heaters, etc.
Another unit of energy measurement, the gigocalorie (Gcal), may be encountered when installing heat meters.
Also, the supplied heat is sometimes indicated in Gcal on payment receipts.
And if the calculation is accepted management company in one unit, and the meter shows another, you may need to monthly convert Gcal to kW and vice versa. Once you understand everything once, you can learn how to do it quickly and easily.
During the construction of buildings, all measurements and thermal calculations are produced in gigacalories. Utilities This unit of measurement is also preferred for its proximity to real life and industrial-scale computing capabilities.
We remember from the school course that a calorie is the work needed to heat 1 gram of water per unit °C (at a certain atmospheric pressure).
In life you have to deal with Kcal and Gcal, gigacalories.
- 1 Kcal = 1 thousand cal.
- 1 Gcal = 1 million Kcal, or 1 Billion. cal.
The following measurement can be used in heating receipts:
- Gcal;
- Gcal/hour.
In the first case, we mean the supplied heat for a certain period (this could be a month, a year or a day). Gcal/hour is a characteristic of the power of a device or process (such a unit of measurement can indicate the performance of a heating device or the rate of heat loss of a building in winter). The receipts imply heat that was released in 1 hour. Then, to recalculate for a day, you need to multiply the number by 24, and for a month by another 30/31.
1 Gcal/hour = 40 m 3 of water, which was heated to 25 °C in 1 hour.
Also, a gigacalorie can be tied to the volume of fuel (solid or liquid) Gcal/m3. And it shows how much heat can be obtained from a cubic meter of this fuel.
How to convert energy units?
On the Internet you can actually find a huge number of online calculators that convert the required values automatically.
When it comes to figuring it all out, there are often lengthy formulas and proportions that can be off-putting to the average consumer who graduated from school many years ago.
But it’s possible to figure everything out! You will need to remember 1 or 2 numbers, an action, and you can easily make the translation offline, on your own.
How to convert kW to Gcal/h
Key indicator for converting data from kilowatts to calories:
1 kW = 0.00086 Gcal/hour
To find out how many Gcal is obtained, you need to multiply the available number of kW by a constant value, 0.00086.
Let's look at an example. Suppose you need to convert 250 kW into calories.
250 kW x 0.00086 = 0.215 Gcal/hour.
(More accurate online calculators will show 0.214961).
The heating season has arrived, but the radiators are still cold? Don’t look for ways to warm yourself, demand respect for your rights. Follow the link for information on where to call and what to do if there is no heating.
Convert Gcal to kW/h
The opposite situation is when you need to convert Gcal to kW. You need to know how many kW contains 1 Gcal
1 Gcal = 1163 kW.
This means that one gigacalorie of heat will need to be consumed to produce 1163 kilowatts of energy.
Or vice versa: 1163 kW of energy will be required to produce one Gcal of heat.
To convert the number of gigocalories you know into kilowatts, you need to multiply the existing Gcal indicator by 1163.
0.5 x 1163 = 581.5 kW.
Conversion table
A quick translation of round numbers can be done using tables:
Conclusion
So, to make it easier to carry out monthly transfers of heat units, you need to remember a couple of numbers and the action that needs to be performed with them.If there is a reading in kilowatts, it must be multiplied by 0.00086 and it will be obtained in gigacalories.
And when the readings are taken in gigacalories, you need to multiply them by 1163 and you get kilowatts.
The procedure for calculating heating in residential buildings depends on the availability of heat meters and how exactly the house is equipped with them. Often, after paying large heating bills again, residents multi-storey buildings They think that somewhere they were deceived. In some apartments you have to freeze every day, in others, on the contrary, they open the windows to ventilate the rooms from the intense heat. In order to completely rid yourself of the need to overpay for excess heat and to save money, you need to decide exactly how to calculate the amount of heat to heat your home. Simple calculations will help solve this, through which it will become clear how much heat must be supplied to the radiators of houses.
What is thermal design?
It represents a primary document for solving the simple problem of heating a home. It determines the minimum requirement of an object for thermal energy, the heat consumption of each room or apartment, the annual and daily heat consumption.
How can you calculate the cost of 1 Gcal and what is included in the price for heat
The cost of a unit of heat - 1 gigacalorie - is calculated by utility services - suppliers of heat and hot water supply based on calculations that are agreed upon with the City Council and approved by the National Commission.
The cost of 1 Gcal includes the price of gas and electricity, repairs of equipment and networks, staff salaries, expenses for various investment programs, operating expenses and much more.
How to perform heat consumption calculations
If suddenly heat meter for one reason or another there is no room in the house, then the following formula for calculating thermal energy is used:
Vx(T1-T2)/1000=Q
Let's look at what these symbols mean:
V - means the amount of hot water consumed, which can be calculated either in cubic meters or in tons.
T1 is DHW temperature(always measured in ordinary degrees Celsius).
T2 in this formula also means temperature, but of cold water supply.
If we talk about the number 1000, then this is the standard coefficient that is used in the formula to get the result in Gcal.
Q - means the total amount of thermal energy.
Usage closed system forces us to slightly improve the above formula, which in this case takes the following form:
Q = ((V1* (T1 - T)) - (V2*(T2 - T))) /1000
V1 is the heat consumption in the supply pipe, regardless of whether the coolant is water or steam;
V2 - heat consumption in the return pipe;
T1 — heater temperature at the inlet, in the supply pipe;
T2 is the temperature of the heater at the outlet, in the return pipe;
T - cold water temperature.
As you can understand, the calculation formula consists of the difference of 2 factors - the first means the value of the heat received in calories, and the second means the value of the heat output. Knowing these formulas, you can independently calculate the thermal energy consumption of your home or apartment without the help of professionals.
