Influence of thermal properties of architectural glass on energy efficiency of sustainable buildings

Abstract

In times of climate change and globalisation, there is a demand for studies that address long-term environmental security, efficient use of energy and other recourses, as well as the preservation of the identity and uniqueness of particular places. Sustainable building involves complex solutions and practices that lead to more energy-efficient houses that consume less energy, water, and other natural resources. It encompasses constructing buildings in such a way as to minimise the material input per unit, and managing them to reduce the power-intensity as well as any negative impact on the health of people or the environment. The concept of sustainable building was developed in other countries, but it is becoming more popular also in Latvia [1; 2]. Sustainable city life is one of the seventeen Global Goals that make up the 2030 Agenda for Sustainable Development; accordingly, an integrated approach is crucial for achieving progress across the multiple goals [3]. In order to increase energy efficiency in buildings, reduce CO2 emissions in the world and prevent global warming, it is very important to pay attention to the thermal properties of skylights. The impact of glazing on the thermal performance of a building is complicated. There are several aspects that need to be considered: the climatic conditions of the location, such as temperature, humidity, sunshine, and wind, as well as the orientation, form and layout of the building, the building materials, especially their mass and insulating properties, the size and location of windows and shading and the thermal properties of glazing systems. The impact of glazing is the result of the interaction of all of these aspects. The aim of this study is to provide some insight into how thermal properties, in particular vertical heat flow, are affected by the thickness of the air separation layer in horizontal and sloped skylights. Glass structures made from organic glass and aerogel layers, which are characterised by a low thermal conductivity coefficient, were studied. An experiment was carried out with different translucent materials (selective glass, organic glass, aerogel filling) and the distance between the glazing layers was varied. The aim was to measure the dependence of the thermal conductivity coefficient on the thickness of the air separation layer and the direction of the heat flow.