Quantitative effects of glass roof system parameters on energy and daylighting performances: A bi-objective optimal design using response surface methodology

Abstract

In regions with a hot-summer/cold-winter climate, a balance between energy-saving and better daylighting performance is often required for the design of a glass roof system. This research aims to reduce the total energy demand and to increase the useful daylight illuminance (UDI), by introducing a response-surface-methodology-based bi-objective optimization approach for three glass roof system models (no shading, exterior blinds, interior shades). Surrogate models were generated to quantify the effect of the glazing material and shading parameters. Our findings have revealed that, in hot-summer/cold-winter climate regions like Nanjing, properties of the glazing material could substitute the effect of shading parameters to enhance energy-saving potentials. However, the use of glazing cannot make up for the effect on the daylight performance. Glass roof systems with a low U-value glazing material and small-slat exterior blinds are generally recommended as the balanced solution to lower the energy demand and raise the UDI200–2000. The substitute relations introduced in the surrogate models and optimal solutions have indicated that there are multiple choices to attain a relatively similar goal to produce an energy-efficient building design for construction.