The effect of ventilation rates determined based on the acceptable risk of COVID-19 infection in classrooms on energy consumption from heating

Öz

In this study, the effect of ventilation rates determined based on acceptable infection risk on the number of COVID-19 cases, probability of infection and heating energy load in various climatic regions in naturally ventilated higher education classrooms during the SARS-CoV-2 pandemic were investigated. Ventilation rates, number of new cases and probability of infection were determined by the Wells-Riley model adapted to SARS-CoV-2, which was used to model the probability of airborne infection. The annual heating energy load was calculated with the EnergyPlus based building energy simulation according to the heat balance method. The proposed method was applied to university classrooms in different climatic regions as a case study. The findings showed that ventilation rates increased by 51,41% on average compared to pre-COVID-19, and the number of daily COVID-19 cases decreased by an average of 63.19% compared to the conditions of the pre-COVID-19 period to ensure an acceptable infection risk in classrooms. The increase in ventilation rates increased the annual heating energy loads of classrooms to 192.37% with 29322 kWh in a temperate climate compared to pre-COVID-19; by 98.80% with 57083 kWh in cold climate; and by 79.21% with 82467 kWh in very cold climates. In universities with naturally ventilated classrooms during the COVID-19 process, the academic year should be determined according to the periods when ventilation is suitable for indoor thermal comfort control. In this case, the energy consumption due to heating is 86.52% in a temperate climate; 69.60% in a cold climate; in very cold climates, it decreases by 61.40%. These results show that we can better prepare for airborne diseases and other possible epidemics in the future, according to climatic differences.

Anahtar Kelimeler

• COVID-19 infection risk
• ventilation rate
• classroom
• heating energy load

Dersliklerde kabul edilebilir COVID-19 enfeksiyon riskine dayalı belirlenen havalandırma oranlarının ısıtmadan kaynaklanan enerji tüketimine etkisi

Öz

Bu çalışmada, SARS-CoV-2 salgınında doğal havalandırılan yükseköğretim dersliklerinde, kabul edilebilir enfeksiyon riskine dayalı belirlenen havalandırma oranlarının COVID-19 vaka sayısına, enfeksiyon olasılığına ve çeşitli iklim bölgelerinde ısıtmadan kaynaklanan enerji tüketimine etkisi araştırılmıştır. Havalandırma oranları, yeni vaka sayısı ve enfeksiyon olasılığı hava kaynaklı enfeksiyon olasılığının modellenmesinde kullanılan SARS-CoV-2’ye uyarlanmış Wells-Riley modeliyle belirlenmiştir. Isıtmadan kaynaklanan enerji tüketimi, ısı dengesi metoduna göre EnergyPlus tabanlı bina enerji simülasyonuyla hesaplanmıştır. Önerilen yöntem, vaka çalışması olarak farklı iklimde bölgelerinde bulunan üniversite dersliklerine uygulanmıştır. Bulgular, dersliklerde kabul edilebilir enfeksiyon riskinin sağlanabilmesi için havalandırma oranlarının COVID-19 öncesine göre ortalama %51,41 arttığını, günlük COVID-19 vaka sayısının ise COVID-19 öncesi dönemin şartlarına göre ortalama %63,19 azaldığını göstermiştir. COVID-19 sürecinde artan havalandırma oranları, dersliklerin ısıtmadan kaynaklı enerji tüketiminin COVID-19 öncesine göre ılıman iklimde %192,37 (29322 kWh); soğuk iklimde %98,80 (57083 kWh); çok soğuk iklimde ise %79,21 (82467 kWh) artmasına sebep olmuştur. COVID-19 sürecinde doğal havalandırılan dersliklere sahip üniversitelerde, eğitim öğretim dönemi, havalandırmanın iç ortam termal konfor kontrolü için uygun olduğu dönemlere göre belirlenmelidir. Bu durumda, ısıtmadan kaynaklanan enerji tüketimi ılıman iklimde %86,52; soğuk iklimde %69,60; çok soğuk iklimde ise %61,40 oranında azalmaktadır. Bu sonuçlar, gelecekte hava yoluyla bulaşan hastalıklara ve olası diğer salgınlara iklimsel farklılıklara göre daha iyi hazırlanılabileceğini göstermektedir.

Anahtar Kelimeler

• COVID-19 enfeksiyon riski
• havalandırma oranı
• derslik
• ısıtma enerji yükü

Kaynakça

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