GENETIC OPTIMIZATION OF EXTERNAL FIXED SHADING DEVICES

A genetic optimization approach has been used for the design of an external shading device in an office with a window and different glass characteristics. The primary energy consumption for heating cooling and lighting have been minimized. Simulations have been performed using the energy code ESP-r and lighting simulation package DaySim, the optimization loop has been driven by the software tool modeFRONTIER. In the present paper a Genetic Optimization (GO) has been carried on an office room with a south facing window. Two different glazing systems have been taken into account, one standard double glass and an high performance glazing system specifically designed to prevent high sun loads. The shading device is a flat panel positioned parallel to the window and inclined by its horizontal axis. The device shades the window from direct sun penetration reducing the cooling loads in summer, but also affecting daylight and heat loads in winter limiting the sun gains, therefore the impact on the overall building energy consumption is investigated. A genetic optimization has been performed for identifying a possible geometry with the lower energy cost impact. Lighting loads computed by the DaySim code have been considered as inputs for the code ESP-r which drives the Energy computation on an hourly basis. The results demonstrate that electrical energy absorbed by the lighting system has to be always taken into account in designing energy efficient shading devices.