Speaker
Description
As humans spend most of their time indoors, most outdoor air pollution exposure occurs inside buildings. It is well-documented that exposure to elevated concentrations of outdoor air pollutants adversely impacts human health. The associated health risks are equivalent, or in some cases more important, to the risks provoked by exposure to indoor emitted air pollutants. To address the issue, well-established building ventilation standards require an outdoor air quality investigation and the application of suitable air filtering methods when the outdoor air is inadequate. However, given that this investigation is usually based on a yearly average representation of outdoor air pollution, it limits the application of technologies that can respond in real-time to indoor and outdoor environmental conditions while providing adequate indoor air quality (IAQ) at minimum energy use. This study addresses the following research question: Can refined knowledge of the relationships between indoor and outdoor air pollutants worldwide result in improved ventilation design that aims to economize energy without compromising IAQ?
Initially, the research focused on the optimization of outdoor air filtration in ventilation systems. As filters provoke a significant pressure drop in the ventilation systems, it is essential to investigate if a more comprehensive knowledge of outdoor air pollution would permit energy savings from the fans’ operation without compromising IAQ. The results obtained through the use of simulations suggest that if the outdoor air filter is bypassed when the outdoor air pollution levels are low, it could economize, on average, 14% of the energy from the fans’ operation without compromising IAQ.
Secondly, we investigated the energy-saving potential natural ventilation (NV) can achieve in buildings by coupling the comprehensive outdoor air pollution data together with building energy simulations. The results revealed that NV can reduce the cooling demand in Europe by 17-100% without increasing the outdoor air pollution penetration indoors. However, outdoor air pollution limited this energy saving on average by 24%, indicating that it is an important limiting factor of the NV potential.
Thirdly, we developed a novel methodology that permits the evaluation of ventilation systems and strategies with regard to their energy efficiency and the health impacts that are provoked to the building occupants as a result of exposure to various air pollutants of indoor and outdoor origin. This novel method permits a better understanding of the tradeoffs between energy, IAQ, and health, and it opens the way to a more efficient ventilation design that can take advantage of current control technologies that can respond in real-time to indoor and outdoor environmental conditions.
In conclusion, the results revealed that energy savings in the ventilation systems are possible without compromising IAQ when the longitudinal outdoor air pollution is considered in the design and operation phases of the building. Designers and building operators can follow the study’s recommendations to design and operate the buildings more efficiently, as well as policymakers can benefit from the results to update the standards and guidelines for more sustainable buildings.
References
[1] E. Belias and D. Licina, “Outdoor PM2.5 air filtration: optimising indoor air quality and energy,” Buildings and Cities, vol. 3, no. 1, Art. no. 1, Apr. 2022, doi: 10.5334/bc.153.
[2] E. Belias and D. Licina, “Influence of outdoor air pollution on European residential ventilative cooling potential,” Energy and Buildings, p. 113044, Apr. 2023, doi: 10.1016/j.enbuild.2023.113044.
| Keywords | outdoor air filtration, outdoor pollution penetration, natural ventilation, Disability Adjusted Life Years |
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