On the failure of the only vernacular windcatcher in the mountainous region of Western Iran: Opportunities for energy-efficient buildings

摘要

Reducing energy consumption in the building sector, which contributes to 30% of energy-related, global CO2 emissions, is of crucial importance in mitigating climate change. Vernacular architectural elements such as windcatchers have been a paramount model in modern sustainable architecture to provide energy-efficient cooling and ventilation using natural forces of wind and buoyancy. Yet the range of climatic conditions in which windcatchers can be widely used and their role in the indoor air quality are unknown. Particularly, despite the widespread use of vernacular windcatchers in desert regions, it is unclear why they have not been applied in mountainous areas. We report on the only vernacular windcatcher in a mountainous region with a Mediterranean-to-cold climate in Western Iran and use computational fluid dynamics (CFD) simulation, long-time climate data, and psychrometric analyses to investigate the reasons for the failure of this windcatcher in becoming widespread in mountainous regions. Our CFD simulation results for a broad range of ambient wind speeds demonstrate that the overall performance of the windcatcher set on the roof of Emad-o-Dowlah Mosque, Kermanshah, Iran, is on average comparable with modern windcatchers studied previously and is significantly (p-value = 0.001) better than natural ventilation and cooling systems merely consisting of window and door openings (by 101%).We further show that while climatic conditions of the region necessitate the use of windcatchers during summer daytime, and the windcatcher's performance is satisfactory in terms of providing comfort, it requires certain technology to shut it off in the night-time that was previously lacking. These results indicate that with today's technology windcatchers are applicable over a broader climatic condition than hitherto expected. Crown Copyright (C) 2021 Published by Elsevier Ltd. All rights reserved.