Multi-factor optimization of energy performance in naturally ventilated building: a case study of office building in hot summer and cold winter climate

Abstract

Nowadays, building energy consumption is responsible for 30% to 40% of total energy usage in many countries. The energy performance of each building is related to many factors. Most of them are determined in design stage. Meanwhile, natural ventilation is one of the most potential passive energy conservation, especially in hot summer and cold winter climate zone. This study aims to figure out how to make the most of natural ventilation in building energy conservation in hot summer and cold winter climate zone. By comparing different building design plans, this study try to provide a method to help find the best-optimized building parameters design solutions. Six main factors are selected, including: building orientation, exterior wall masonry, window wall ratio, shading overhang depth, binds slat angel(include the situation when there is no blinds at all), exterior window structure. A seven-layer office building in hot summer and cold winter zone is modelled and simulated in Energyplus. Two building running plans are compared: (a) the air conditioning system is always on during office occupancy time; (b) the air conditioning system is off when natural ventilation can guarantee thermal comfort inside the building. The results shows, plan (b) saves more than 40% energy on different building parameters designs comparing to plan (a).