Skip to main content
NCBI home page
Springer Nature - PMC COVID-19 Collection logoLink to Springer Nature - PMC COVID-19 Collection
. 2023 Mar 26;16(5):667–682. doi: 10.1007/s12273-023-1000-x

A cost-effectiveness assessment of the operational parameters of central HVAC systems during pandemics

Yufan Chang 1,2, Zhengtao Ai 1,2,✉, Jinjun Ye 1,2, Guochuan Ma 3
PMCID: PMC10040913  PMID: 37101942

Abstract

The present study develops a cost-effectiveness assessment model to analyze the performance of major operational parameters of central HVAC systems in terms of airborne transmission risk, energy consumption, and medical and social cost. A typical multi-zone building model with a central HVAC system is built numerically, and the effect of outdoor air (OA) ratio (from 30% to 100%) and filtration level (MERV 13, MERV 16, and HEPA) are assessed under the conditions of five climate zones in China. Compared with the baseline case with 30% OA and MERV 13 filtration, the airborne transmission risk in zones without infector is negligibly reduced with the increase in OA ratio and the upgrade of filtration level, owing to their slight modification on the equivalent ventilation rate of virus-free air. However, depending on climate zone, a 10% increase in OA ratio results in 12.5%–78.6% and 0.1%–8.6% increase in heating and cooling energy consumption, respectively, while an upgrade of filtration level to MERV 16 and HEPA results in an increase of 0.08%–0.2% and 1.4%–2.6%, respectively. Overall, when compared to the use of 100% OA ratio and HEPA filtration, the application of 30% or 40% OA ratio and MERV 13 filtration would save annually an energy and facility related cost of $29.4 billion in China, though giving an increase of approximately $0.1 billion on medical and social cost from the increased number of confirmed cases. This study provides basic method and information for the formulation of cost-effective operational strategies of HVAC systems coping with the airborne transmission, especially in resource-limited regions.

Keywords: outdoor air ratio, filtration level, airborne transmission risk, energy consumption, cost-effectiveness

Acknowledgements

This study was supported by the National Natural Science Foundation of China (No. 51908203) and by the Fundamental Research Funds for the Central Universities (No. 531118010378).

List of symbols

B

benefit

C

cost

D

numbers of new infectors

EM

mask index

fI

fraction of infectors who wear masks

fN

OA ratio

ft

fraction of susceptible individuals who wear masks

I

number of initial infectors

p

pulmonary ventilation rate of susceptible individuals

PI

probability of airborne transmission risk (%)

q

quantum generation rate (h−1)

Q

ventilation rate (m3/s)

S

number of susceptible individuals

T

cost-effective analysis time period

t

exposure time (h)

ε

filtration efficiency

ηI

exhalation filtration efficiency

ηt

inhalation filtration efficiency

Abbreviations

ASC

Architectural Society of China

ASHRAE

American Society of Heating, Refrigerating and Air-Conditioning Engineers

BCR

benefit-cost ratio

CABR

China Academy of Building Research

CCIAQ

Canadian Committee on Indoor Air Quality

COP

coefficient of performance

GDP

gross domestic product

HEPA

high-efficiency particulate air

HVAC

heating, ventilation, and air-conditioning

ISHRAE

Indian Society of Heating Refrigerating and Air Conditioning Engineers

MERV

minimum efficiency reporting value

NBS

National Bureau of Statistics of China

OA

outdoor air

TMY

typical meteorological year

Subscripts

i

ventilation rate in each zone

r

discount rate

R

return air

total

total ventilation rate in the HVAC system

vf

virus-free air

References

  1. Ai Z, Hashimoto K, Melikov AK. Airborne transmission between room occupants during short-term events: measurement and evaluation. Indoor Air. 2019;29:563–576. doi: 10.1111/ina.12557. [DOI] [PubMed] [Google Scholar]
  2. Amoatey P, Omidvarborna H, Baawain MS, et al. Impact of building ventilation systems and habitual indoor incense burning on SARS-CoV-2 virus transmissions in Middle Eastern countries. Science of the Total Environment. 2020;733:139356. doi: 10.1016/j.scitotenv.2020.139356. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Asad HS, Yuen RKK, Liu J, et al. Adaptive modeling for reliability in optimal control of complex HVAC systems. Building Simulation. 2019;12:1095–1106. doi: 10.1007/s12273-019-0558-9. [DOI] [Google Scholar]
  4. ASC (2020). Guidelines for office buildings to deal with “new coronavirus” operational management emergency measures. Architectural Society of China (ASC). (in Chinese)
  5. ASHRAE . ASHRAE Standard 62. Ventilation for Acceptable Indoor Air Quality. Atlanta, GA, USA: American Society of Heating, Refrigerating and Air-Conditioning Engineers; 1989. [Google Scholar]
  6. ASHRAE . Climatic Data for Building Design Standards, 15. Atlanta, GA, USA: American Society of Heating, Refrigerating and Air-Conditioning Engineers; 2013. [Google Scholar]
  7. ASHRAE (2020a). ASHRAE Epidemic Task Force for Schools and Universities. Available at https://www.ashrae.org/file%20library/technical%20resources/covid-19/ashrae-reopening-schools-and-universities-c19-guidance.pdf
  8. ASHRAE (2020b). ASHRAE Position Document on Airborne Infectious Aerosols. Available at https://www.ashrae.org/file%20library/about/position%20documents/pd_infectiousaerosols_2020.pdf
  9. Azimi P, Stephens B HVAC filtration for controlling infectious airborne disease transmission in indoor environments: Predicting risk reductions and operational costs. Building and Environment. 2013;70:150–160. doi: 10.1016/j.buildenv.2013.08.025. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. CABR (2015a). GB50189-2015. Design Standard for Energy Efficiency of Public Buildings. China Academy of Building Research. (in Chinese)
  11. CABR (2015b). GB50736-2015. Design Code for Heating Ventilation and Air Conditioning of Civil Buildings. China Academy of Building Research. (in Chinese)
  12. CABR (2019). JGJ475-2019. Standard for Design of Energy Efficiency of Residential Buildings in Moderate Climate Zone. China Academy of Building Research. (in Chinese)
  13. Chua KJ, Chou SK, Yang WM, et al. Achieving better energy-efficient air conditioning—A review of technologies and strategies. Applied Energy. 2013;104:87–104. doi: 10.1016/j.apenergy.2012.10.037. [DOI] [Google Scholar]
  14. Coibion O, Gorodnichenko Y, Weber M (2020). The cost of the COVID-19 crisis: Lockdowns, macroeconomic expectations, and consumer spending. National Bureau of Economic Research. Available at 10.3386/w27141 [DOI]
  15. Dai H, Zhao B. Association of the infection probability of COVID-19 with ventilation rates in confined spaces. Building Simulation. 2020;13:1321–1327. doi: 10.1007/s12273-020-0703-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Dai H, Zhao B. Association between the infection probability of COVID-19 and ventilation rates: An update for SARS-CoV-2 variants. Building Simulation. 2023;16:3–12. doi: 10.1007/s12273-022-0952-6. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Davies A, Thompson KA, Giri K, et al. Testing the efficacy of homemade masks: would they protect in an influenza pandemic? Disaster Medicine and Public Health Preparedness. 2013;7:413–418. doi: 10.1017/dmp.2013.43. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Demetriou DW, Khalifa HE. Evaluation of distributed environmental control systems for improving IAQ and reducing energy consumption in office buildings. Building Simulation. 2009;2:197–214. doi: 10.1007/s12273-009-9320-z. [DOI] [Google Scholar]
  19. Duan X, Zhao X, Wang B . Exposure Factors Handbook of Chinese Population (Adults) Beijing: China Environmental Science Press; 2013. [Google Scholar]
  20. ECDC (2020). Guidelines for the implementation of non-pharmaceutical interventions against COVID-19. European Centre for Disease Prevention and Control. Available at https://www.ecdc.europa.eu/sites/default/files/documents/covid-19-guidelines-non-pharmaceutical-interventions-september-2020.pdf
  21. Faulkner CA, Castellini JE, Jr, Zuo W, et al. Investigation of HVAC operation strategies for office buildings during COVID-19 pandemic. Building and Environment. 2022;207:108519. doi: 10.1016/j.buildenv.2021.108519. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Gao J, Yuan Z, Liu X, et al. Improving air pollution control policy in China—A perspective based on cost-benefit analysis. Science of the Total Environment. 2016;543:307–314. doi: 10.1016/j.scitotenv.2015.11.037. [DOI] [PubMed] [Google Scholar]
  23. Ginestet A, Pugnet D, Mouradian L (2013). Filter pressure drop control in balanced ventilation systems for dwellings. In: Proceedings of the 34th AIVC Conference and 3rd TightVent Conference, Athens, Greece.
  24. Han X, Guo J, Wei C. Residential space-heating energy demand in urban Southern China: An assessment for 2030. Energy and Buildings. 2022;254:111598. doi: 10.1016/j.enbuild.2021.111598. [DOI] [Google Scholar]
  25. Hanley N, Barbier EB. Pricing Nature: Cost-Benefit Analysis and Environmental Policy. Cheltenham, UK: Edward Elgar Publishing; 2009. [Google Scholar]
  26. HCB (2021). Report on energy consumption monitoring of large public buildings in Shenzhen (2020). Housing and Construction Bureau of Shenzhen Municipality. (in Chinese)
  27. HURD (2021). Shanghai Municipal Office Buildings and Large-scale Public Buildings Energy Consumption Monitoring and Analysis Report (2020). Shanghai Municipal Administrative Committee of Housing and Urban-Rural Development. (in Chinese)
  28. ISHRAE (2020). ISHRAE COVID-19 Guidance Document for Air Conditioning and Ventilation. Indian Society of Heating, Refrigerating & Air Conditioning Engineers.
  29. Jin H, Wang H, Li X, et al. Economic burden of COVID-19, China, January`-March, 2020: A cost-of-illness study. Bulletin of the World Health Organization. 2021;99:112–124. doi: 10.2471/BLT.20.267112. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Lee BU. Minimum sizes of respiratory particles carrying SARS-CoV-2 and the possibility of aerosol generation. International Journal of Environmental Research and Public Health. 2020;17:6960. doi: 10.3390/ijerph17196960. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Liu Y, Zhou B, Wang J, et al. Health benefits and cost of using air purifiers to reduce exposure to ambient fine particulate pollution in China. Journal of Hazardous Materials. 2021;414:125540. doi: 10.1016/j.jhazmat.2021.125540. [DOI] [PubMed] [Google Scholar]
  32. Lu J, Gu J, Li K, et al. COVID-19 Outbreak Associated with Air Conditioning in Restaurant, Guangzhou, China, 2020. Emerging Infectious Diseases. 2020;26(7):1628–1631. doi: 10.3201/eid2607.200764. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Luo H, Zhong L. Ultraviolet germicidal irradiation (UVGI) for in-duct airborne bioaerosol disinfection: Review and analysis of design factors. Building and Environment. 2021;197:107852. doi: 10.1016/j.buildenv.2021.107852. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Lv Y, Peng H, He M, et al. Definition of typical commercial building for South China’s Pearl River Delta: Local data statistics and model development. Energy and Buildings. 2019;190:119–131. doi: 10.1016/j.enbuild.2019.02.035. [DOI] [Google Scholar]
  35. Mallach G, Kasloff SB, Kovesi T, et al. Aerosol SARS-CoV-2 in hospitals and long-term care homes during the COVID-19 pandemic. PLoS One. 2021;16:e0258151. doi: 10.1371/journal.pone.0258151. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. MOHURD (2016). GB 50176-2016. Code for Thermal Design of Civil Building. Ministry of Housing and Urban-Rural Development of China. (in Chinese)
  37. Nakhaei K, Jalilian H, Arab-Zozani M, et al. Direct and indirect cost of COVID-19 patients in Iran. Health Policy and Technology. 2021;10:100572. doi: 10.1016/j.hlpt.2021.100572. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. National Health Commission of China (2022). Outbreak Notification. Available at http://www.nhc.gov.cn/xcs/yqtb/list_gzbd.shtml. (in Chinese)
  39. National Healthcare Security Administration (2020). Statistical Snapshot of Medicare Business Development in 2020. Available at http://www.gov.cn/xinwen/2021-03/08/content_5591551.htm. (in Chinese)
  40. NBS (2021). The Seventh National Census Bulletin (No. 2). National Bureau of Statistics of China. Available at http://www.stats.gov.cn/tjsj/tjgb/rkpcgb/qgrkpcgb/202106/t20210628_1818821.html. (in Chinese)
  41. NBS (2022). Statistical Communique of the People’s Republic of China on the 2021 National Economic and Social Development. Available at http://www.gov.cn/shuju/2022-02/28/content_5676015.htm. (in Chinese)
  42. Pang Z, Lu X, O’Neill Z (2022). Quantification of how mechanical ventilation influences the airborne infection risk of COVID-19 and HVAC energy consumption in office buildings. Building Simulation, 10.1007/s12273-022-0937-5 [DOI] [PMC free article] [PubMed]
  43. Pistochini T, Mande C, Chakraborty S. Modeling impacts of ventilation and filtration methods on energy use and airborne disease transmission in classrooms. Journal of Building Engineering. 2022;57:104840. doi: 10.1016/j.jobe.2022.104840. [DOI] [Google Scholar]
  44. Prather KA, Marr LC, Schooley RT, et al. Airborne transmission of SARS-CoV-2. Science. 2020;370(6514):303–304. doi: 10.1126/science.abf0521. [DOI] [PubMed] [Google Scholar]
  45. REHVA (2020). REHVA COVID-19 Guidance Document. Federation of European Heating, Ventilation and Air Conditioning Associations. Available at https://nchh.org/resource-library/rehva_covid-19-guidance-document_2020.03.17.pdf
  46. Ren J, Liu J, Cao X, et al. Influencing factors and energy-saving control strategies for indoor fine particles in commercial office buildings in six Chinese cities. Energy and Buildings. 2017;149:171–179. doi: 10.1016/j.enbuild.2017.05.061. [DOI] [Google Scholar]
  47. Ruan T, Rim D. Indoor air pollution in office buildings in mega-cities: Effects of filtration efficiency and outdoor air ventilation rates. Sustainable Cities and Society. 2019;49:101609. doi: 10.1016/j.scs.2019.101609. [DOI] [Google Scholar]
  48. Sosnowski TR. Inhaled aerosols: Their role in COVID-19 transmission, including biophysical interactions in the lungs. Current Opinion in Colloid & Interface Science. 2021;54:101451. doi: 10.1016/j.cocis.2021.101451. [DOI] [PMC free article] [PubMed] [Google Scholar]
  49. State Council of the People’s Republic of China (1983). State Council Temporary Measures on Workers’ Retirement, Resignation. Available at http://www.gd.gov.cn/zwgk/wjk/zcfgk/content/post_2531473.html. (in Chinese)
  50. Tang B (2021). The most bizarre virus spread in Xi’an. Available at https://mp.weixin.qq.com/s/ht0FYhEtlEKoKHncSuZnXQ. (in Chinese)
  51. The Guardian (2022). Dr Anthony Fauci: Long Covid is an ‘insidious’ public health emergency. Available at https://www.theguardian.com/society/2022/oct/17/fauci-interview-long-covid-risk-emergency-response-coronavirus
  52. van der Zee SC, Strak M, Dijkema MA, et al. The impact of particle filtration on indoor air quality in a classroom near a highway. Indoor Air. 2017;27:291–302. doi: 10.1111/ina.12308. [DOI] [PubMed] [Google Scholar]
  53. Wang D, Hu B, Hu C, et al. Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus-infected pneumonia in Wuhan, China. JAMA. 2020;323:1061–1069. doi: 10.1001/jama.2020.1585. [DOI] [PMC free article] [PubMed] [Google Scholar]
  54. Wang CC, Prather KA, Sznitman J, et al. Airborne transmission of respiratory viruses. Science. 2021;373(6558):eabd9149. doi: 10.1126/science.abd9149. [DOI] [PMC free article] [PubMed] [Google Scholar]
  55. WHO (2022a). Coronavirus Disease (COVID-19) Pandemic. World Health Organization. Available at https://www.who.int/emergencies/diseases/novel-coronavirus-2019.
  56. WHO (2022b). Statement on the thirteenth meeting of the International Health Regulations (2005) Emergency Committee regarding the coronavirus disease (COVID-19) pandemic. World Health Organization. Available at https://www.who.int/news/item/18-10-2022-statement-on-the-thirteenth-meeting-of-the-international-health-regulations-(2005)-emergency-committee-regarding-the-coronavirus-disease-(covid-19)-pandemic.
  57. Xu D, Boncoeur S, Tan G, et al. Energy saving potential of a fresh air pre-cooling system using radiative sky cooling. Building Simulation. 2022;15:167–178. doi: 10.1007/s12273-021-0802-y. [DOI] [Google Scholar]
  58. Yan S, Wang L, Birnkrant MJ, et al. Evaluating SARS-CoV-2 airborne quanta transmission and exposure risk in a mechanically ventilated multizone office building. Building and Environment. 2022;219:109184. doi: 10.1016/j.buildenv.2022.109184. [DOI] [PMC free article] [PubMed] [Google Scholar]
  59. Yu H, Xin X. Demand elasticity, Ramsey index and cross-subsidy scale estimation for electricity price in China. Sustainable Production and Consumption. 2020;24:39–47. doi: 10.1016/j.spc.2020.06.008. [DOI] [Google Scholar]
  60. Zaatari M, Novoselac A, Siegel J. The relationship between filter pressure drop, indoor air quality, and energy consumption in rooftop HVAC units. Building and Environment. 2014;73:151–161. doi: 10.1016/j.buildenv.2013.12.010. [DOI] [Google Scholar]
  61. Zhang Z, Li X, Wang Q, et al. Field simulation of aerosol transmission of SARS-CoV-2 in a special building layout—Guangdong Province, China, 2021. China CDC Weekly. 2021;3:711–715. doi: 10.46234/ccdcw2021.176. [DOI] [PMC free article] [PubMed] [Google Scholar]
  62. Zheng W, Hu J, Wang Z, et al. COVID-19 impact on operation and energy consumption of heating, ventilation and air-conditioning (HVAC) systems. Advances in Applied Energy. 2021;3:100040. doi: 10.1016/j.adapen.2021.100040. [DOI] [Google Scholar]
  63. Zuraimi MS, Tham KW. Reducing particle exposures in a tropical office building using electrostatic precipitators. Building and Environment. 2009;44:2475–2485. doi: 10.1016/j.buildenv.2009.04.011. [DOI] [Google Scholar]

Articles from Building Simulation are provided here courtesy of Nature Publishing Group

RESOURCES