Analysis of energy saving potential using shadings and natural ventilation in four major cities in China

There are generally two ways for building energy saving, namely to improve the efficiency of various devices such as HVACs and lighting systems, and to reduce the building loads by using shadings and natural ventilation. While most existing studies focus on the first way, the second way does not increase any hardware investments and can be easily implemented in existing buildings, and thus is the focus of this paper. In order to understand the energy saving potentials, we compare optimal joint controls of shadings and natural ventilation in four cities in China in typical days in summer. Numerical results show that the optimal controls of shadings in different cities do not change much and provide constant energy saving, while the optimal controls of natural ventilation differ greatly but contribute more in energy saving.