Assessment of the Actual and Required Cooling Demand for Buildings with Extensive Transparent Surfaces

Abstract

Energy consumption in buildings with large, glazed facades rises markedly in the summer, driven by cooling demands that vary with structural characteristics and external climate conditions. This study is unique in examining daily cooling needs in lightweight and heavyweight constructions, utilizing meteorological data from 782 summer days in Debrecen, Hungary. Unlike standard approaches, which often overlook localized meteorological variables, this analysis focuses on actual “clear sky” scenarios across distinct summer day types: normal, hot, and torrid. The findings indicate that orientation and construction type significantly affect cooling demands, with east-facing rooms demanding up to 14.2% more cooling in lightweight structures and up to 35.8% in heavyweight structures during peak hours (8 a.m. to 4 p.m.). This study reveals that for west-facing facades, extending use beyond 4 p.m. markedly increases energy loads. Furthermore, the cooling demand peak for heavyweight buildings occurs later in the day, driven by their higher thermal capacity. These insights underscore the importance of aligning HVAC system design with operational schedules and building orientation, offering data-driven strategies to enhance energy efficiency in buildings with diverse thermal and solar exposure profiles.

Keywords

• operative temperature
• cooling demand
• hottest days
• global radiation