Benefits of night temperature setback in the control strategy of the district heating system
MATEC Web of Conferences
Reducing heating system performance by applying a temperature setback as a means of saving heating costs is a well-known and widely used practice. There are discussions about setback achievements, especially about the amount of real savings it brings. However, it is not easy to declare any number - a percentage, because not only most of the heated objects are different, but especially the effects that affect them - from the location of building to demand and user behavior. In real life, heat
... real life, heat consumers apply different setbacks to their heating systems, that is a fact, and from the heat supplier's point of view, it is desirable to adopt this consumer behavior and plan a central heat supply more efficiently with a view to this fact. This article focuses on this issue. It shows the results of a practical experiment that took place in the heating season 2018/2019 in the local district heating system. The experiment carried out was that half the heating season was the temperature of the heating water determined only based on the heating curve coming from the current outdoor temperature, and for the second half of the season was applied night setback - for 5 hours every day, the temperature was lower by 10%. Evaluating the experiment showed a decrease in the demanded heat of about 8% compared to the first part of the heating season. All this savings cannot be unambiguously attributed to the applied setback, because every part of the heating season has its specifics, but as the article shows a value of about 2.4%, it seems real. Contribution in the range of several percent may not at first glance seem attractive, but if we consider that the introduction of the setback procedure does not usually mean extra cost and also the district heating systems require to deliver daily hundreds of gigajoules of the heat (considering a small town), each saved percentage has its value. At the same time, this article highlights other minor improvements that could introduce additional, maybe small but perhaps exciting savings.