Solar Chimneys as an Effective Ventilation Strategy in Multi-Storey Public Housing in the Post-COVID-19 Era

Abstract

This paper studies the effectiveness of a solar chimney for improving ventilation and air-exchange rates in multi-storey public housing in tropical climates for the potential mitigation of airborne disease transmission. Virtual models of a typical apartment room with natural cross-ventilation, replicated across four levels to mimic a multi-storey block, were set up with six internal wind velocity sensor points per floor. The simulation software Energy2D was then used to evaluate the performance of the models, first testing the presence of a solar chimney, and then additionally the degree to which the solar chimney model was affected by a complementary ceiling fan. Wind velocity was also measured, as this is a variable that affects ACH rates. Using a non-parametric Wilcoxon signed-rank test, the introduction of a solar chimney was found to have a significant impact on air-flow rates (a variable that positively affects air-exchange rates), resulting in a p-value of 0.000 and Z-value of −3.920. Regression analysis determined that the solar chimney’s effect was enhanced when complemented by a ceiling fan (R-squared value of 0.4687). Consequently, we propose several design strategies that may enable the adoption of the solar chimney concept to improve natural ventilation in residential units.

Solar Chimney Performance Driven Air Ventilation Promotion: An Investigation of Various Configuration Parameters

“…Indoor thermal comfort is associated with efficient ventilation systems either mechanically or naturally, and accounts for 35 to 40 percent of the country's electrical demand consumed by the residential sector [36]. Therefore, both natural ventilation and thermal comfort in buildings are associated with several solutions such as atria, courtyards, wind towers, double façades, Trombe walls, and SCs [22,36,62].…”

“…Therefore, an increasing recognition of the importance of energy-efficient and environmentally friendly approaches in providing the building design has emphasized the incorporation of natural ventilation solutions in buildings [12][13][14][15][16]. Passive solutions for buildings can provide high durability to promote indoor air quality (IAQ) and indoor thermal comfort and decrease the energy consumption, besides the carbon footprint, by using passive ventilation solutions including, in particular, atria, courtyards, double walls, wind towers, and solar chimneys (SCs) [12,[17][18][19][20][21][22]. SCs can be considered as a significant green passive design solution that can enhance both passive ventilation and solar energy proportionately [23][24][25][26][27][28][29].…”

The Impact of High-Density Urban Wind Environments on the Distribution of COVID-19 Based on Machine Learning: A Case Study of Macau

“…At present, some scholars have explored this. For example, the urban wind environment is closely related to the pollutant index, which will increase the risk of disease transmission [7][8][9][10][11]. Researchers have also explored geometric design parameters and the infection possibility of courtyards under calm wind conditions [12]; natural ventilation conditions have been shown to effectively reduce the risk of COVID-19 spreading in open offices [13]; a semantic similarity model based on point of interest (POI) selection was used to explore the natural ventilation potential (NVP) of four basic residential layouts (point layout, parallel layout, central layout, and mixed layout) in Wuhan to evaluate measures to improve urban ventilation [14]; using Design-Builder (licensed version) and Autodesk CFD software (student version), researchers performed simulations to compare the amount of natural ventilation and lighting before and after modifying the shape of the building, and then they obtained a multi-story residential design adapted to COVID-19 [15].…”

Architecture for a Post-COVID World

“…While academic and practitioner interest in green and healthy architecture existed before, the global impact of COVID-19 spurred on a variety of research with increasing numbers of papers in 2020 and 2021 [6,7]. Given that SARS-Cov-2 is an airborne virus, spreading primarily through the inhaling of, or contact with, aerosols and droplets, and given that airborne viruses can persist in poorly ventilated spaces, it is not surprising that a central thread common to most papers in this Special Issue are concerns relating to adequate ventilation and air exchange that need to be addressed in any post-COVID design [6][7][8][9][10][11][12][13][14]. Ducted (reticulated) heating, ventilation and air-conditioning (HVAC) systems, or airconditioning mechanical ventilation (ACMV) systems in those countries that do not require heating, are prevalent in most office complexes, hotels, medical and educational facilities as well many private homes.…”

“…The majority of design solutions are based on engineering controls with closed systems, although external ventilation through window openings is frequently advocated. The paper by Leng et al builds on the concept of natural ventilation and advocates, where climatologically feasible, for the use of solar (thermal) chimneys (which relies on the convection of air heated by passive solar energy) to be augmented by low-powered ceiling fans [12]. Likewise, the hospital design options discussed by Amran et al make use of large atria as suppliers of fresh outside air [13], while internal light shafts could function as room exhausts.…”