Level of heat loss of heating systems in existing buildings

Abstract

Energy consumption in buildings is largely dependent on losses through the building envelope and through engineering systems.

It is known that the largest losses in engineering systems occur at the stage of transportation of energy resources to the building, as well as in places where they are located in unheated premises. Therefore, it is very important to provide high-quality, full-fledged insulation of engineering systems to minimize energy losses.

A significant number of heating systems currently operating in our buildings were designed and commissioned more than 30 years ago. The materials and thickness of insulation used at that time differ significantly from the current requirements set out in Annex B of the relevant DBN.

It should also be noted that the condition of the pipelines themselves is quite different. In some buildings, although not insulated, they are well maintained, painted, and protected from moisture. In others, the pipelines are in disrepair, the walls are covered with rust, leaking in places, and can lead to an emergency.

Comparing the dependence of heat loss changes in insulated and non-insulated pipelines, we can note the similarity of their character in the form of a polynomial of degree 3.

It is also worth noting that the heat loss of pipelines with outer diameters of 50 mm or more increases sharply (in uninsulated pipelines) or gradually (in insulated pipelines).

During the heating period, the level of losses corresponds to the temperature of the heat carrier in the system, and therefore to the ambient temperature. For pipelines of other diameters, we observe a similar dependence.

Regardless of the diameter of the pipelines, losses in non-insulated pipelines significantly depend on the temperature of the heat carrier and fluctuate within significant limits. Losses in insulated pipelines fluctuate within insignificant limits. The highest losses will occur in January, and the lowest - in April. We do not take into account the months when there is no heating.

An average heating system in a five-story building with damaged or missing insulation will lose UAH 378,294.3 during the heating season compared to a well-insulated one. On average, buildings that have been in operation for a long time can usually have localized damage or lack of insulation in the amount of up to 30% for various reasons. In this case, the cost of losses in such systems will amount to UAH 113488.3.