The influence of different water efficiency ratings of taps and mixers on energy and water consumption in buildings

Abstract

This paper analyses two different models (methods) used for determination of water consumption in residential buildings. For this purpose, some basic sanitation facilities were implemented in the models as typical household equipment. As there is a big variety of sanitary solutions available, in order to achieve a significant reduction in water consumption, a novel classification of faucets (taps and mixers) is proposed. This classification also allows for the assessment of energy efficiency ratings of sanitary appliances. On the basis of this classification, water savings resulting from the use of faucets with different water efficiency ratios were determined. Depending on the type of faucet, it is possible to achieve more than 50% water savings, as well as a significant reduction in energy demand for heating and pumping water to customers. The paper also discusses the equations used to determine the energy demand for domestic hot-water preparation and its pumping to consumers. The results of the energy consumption calculations for the above-mentioned purposes were determined per person.