A simple building energy model in form of an equivalent outdoor temperature

Abstract

Abstract Smart control of energy supply to the existing buildings may increase their energy efficiency. However, to the best of the authors’ knowledge, there are no simple, general, automated, widely applicable and accurate methods for the creation of energy model of the building, which may be used to calculate the actual energy consumption of a heating system or for their prediction. This work presents a new simplified method for generating the energy characteristics of buildings and their heating systems, without the influence of occupants. The method requires as input only the actual heat supplied to the heating system and the local outdoor weather conditions (i.e. temperature, wind speed and solar insolation) of a building. The output is a building energy model in terms of an equivalent outdoor temperature. It was found that when determining the correction due to the wind, the data from the night hours (e.g. from 11.00\xa0p.m. to 4.00\xa0a.m.) should be used in order to exclude the impact of solar radiation and minimize the interaction of users. On the other hand, the correction due to the influence of solar radiation should be obtained using data with low wind speeds and time periods from 10.00\xa0a.m. to 2.00\xa0p.m. on weekdays for residential buildings or from 10.00\xa0a.m. to 2.00\xa0p.m. on the weekend for public buildings in order to minimize disruptive effects of wind speed and the impacts from occupants. This method may be used to generate a simple building energy model and to accurately determine the duration and the amount of heat power supplied to a building for space heating, for periods when the impact of occupants and other internal heat gains are kept to a minimum.