Effects of solar radiation asymmetry on buildings’ cooling energy needs

Abstract

Over the last several years, the energy used for air conditioning in buildings increased in most European countries because of the high heat loads during the summer and the occupants’ increased comfort needs. The aim of our research was to determine the incident solar radiation on horizontal and vertical surfaces and to investigate the heat loads of buildings with different orientations of the glazed areas and different thermal masses in the building structures. Using the measured hourly global radiation data for the years 2009–2013, the diffuse and direct incident solar radiation was determined for the horizontal and vertical surfaces. A statistical analysis of the daily energy yield from solar radiation and the daily mean outdoor temperatures was conducted. The number of symmetric and asymmetric days was determined for torrid days. Using the methodology provided by standard EN ISO 13790:2008, the cooling energy demand and daily energy need for cooling was determined and evaluated for representative days of the analyzed years.