Computational studies on the airflow developed by the building-integrated passive solar energy system

Abstract

Ventilation and cooling demand are expected to rise in the next decades. Sustainable standalone solar passive air ventilation technique could be one of the clean options. In this study, a building-integrated passive solar energy technology (BIPSET) consists solar photovoltaic (PV) and solar still, was implemented for attaining multiple outputs, such as air ventilation, power and clean water in a building prototype proposed based on Chief Minister's solar powered green house scheme, Government of India. Solar PV and solar still were connected separately with single chimney using necessary duct connections. The heat gain in the PV panels was used for air ventilation inside the building. Computational fluid dynamics analysis was carried out in SOLIDWORKS-2017 Flow simulation software to study the airflow behaviour, such as air change per hour, heat gain and efficiencies in the building-integrated system. The results are in good agreement with experimental values for both sunny and cloudy conditions. This solar still duct arrangement reduced the airflow inside the building in noon hours by 30%. However, it improved the airflow by 8% in the evening hours. The present system is in accordance with standards like ASHRAE 62.1–2010 and GRIHA, which indicates its commercial applicability. Moreover, the environment analysis indicates that the system offers CO2 savings of 17.5 kg/year by adopting passive air ventilation. A modified integrated system was proposed to utilize the heat energy from the solar still for air ventilation by altering the duct arrangements.