Do climatic conditions affect the final price of heating?

The knowledge of climatic conditions in the given year is necessary when determining the expenses connected to heating. This factor has a major impact on the height of the price.


What is a heating period?

Typically, a heating period  starts on the 1st September of a given year and ends on the 31st of May of the following year. Heating term is a technical term, but not an accounting term. During the heating term the appliances must be in standby technical condition, so that heating could at any time be started and maintained.


When is the heat being delivered?

The distributor begins to deliver thermal power if and when the exterior daily temperature during the heating period falls under the level of 13° C in two consecutive days and, according to the weather forecast, its rise is not to be expected.  The figure of average exterior daily temperature is one quarter of the addition of exterior temperatures measured at 7am, 2pm and 9pm (the last figure is added twice), in the shade and discounting the impact of heat radiation from the walls of surrounding buildings.  The monitoring and evaluation is conducted by the authorized office of Hydrometeorological Institute (for the area of Komárno it is the observatory in Hurbanovo).


Is the designed heating system sufficient?

In order to properly size the heating system we need to know the so called computational exterior temperature, which is based on the average temperature of the coldest five consecutive days, as per long term meteorological observation. For the area of Slovak Republic, the basic computing temperatures were chosen to be -12, -15, and -18° C.  The area of Komárno and its surroundings falls into the category of -12° C. The height of heat consumption for heating a property is determined by the thermal-technological characteristics of its outer shell (by the thermal power loss of said property) and the level of climatic difficulty of a given accounting period. The yearly amount of thermal power necessary for heating a property can be (approximately) estimated by the so-called Heating Degree Day method, also known as Graden method of computing heat. Simplified it is based on this equation:


-3Qr = 3,6 . 24 . 10 . e . Qc .d. t is-t es)( ti-te)


QrYearly amount of thermal power for heating (GJ/year)

ecorrection factor expressing various operational changes (for flats typically 0,75)

QcHeat loss of the object during the computing exterior temperature (kW)

dNumber of heating days during the heating period (typically 198-210)

t isAverage interior temperature of the object (typically 21° C with the variation of (t i -1)° C to (ti+3)° C

t esAverage exterior temperature during the heating days in the given area

tiComputable interior temperature of the object, typically 21° C with the variation of (t i -1)° C to (ti+3)° C

teComputable exterior temperature in the given area (Komárno -12° C)


Which year was the warmest and which one the coldest?

Climatic conditions of a given year are determined by the number of day degrees. Day degrees show the difference between day degrees between the interior and exterior temperature during heating. The number of day degrees reached:

Year                                Number of day degrees

2007                                3 339,9

2008                                3 308,9

2009                                3 232,5

2010                                3 839,9

2011                                3 560,2

2012                                3 464,5

2013                                3 614,4

2014                                3 183,9

2015                                3 437,2

2016                                3 550,2

2017                                3 816,4

2018                                3 290,0

2019                                3 368,0

2020                                3 314,0

As the chart shows, the coldest year with the highest number of day degrees in the last decade was the year 2010, and the warmest year with the lowest number of day degrees was year 2014.