Revising the definition of anthropogenic heat flux from buildings: role of human activities and building storage heat flux

Liu, Y., Luo, Z. ORCID: https://orcid.org/0000-0002-2082-3958 and Grimmond, S. ORCID: https://orcid.org/0000-0002-3166-9415 (2022) Revising the definition of anthropogenic heat flux from buildings: role of human activities and building storage heat flux. Atmospheric Chemistry and Physics, 22. pp. 4721-4735. ISSN 1680-7316 doi: 10.5194/acp-22-4721-2022

Abstract/Summary

Buildings are a major source of anthropogenic heat emissions, impacting energy use and human health in cities. The difference between building energy consumption and building anthropogenic heat emission magnitudes and time lag and are poorly quantified. Energy consumption (QEC) is a widely used proxy for the anthropogenic heat flux from buildings (QF,B). Here we revisit the latter’s definition. If QF,B is the heat emission to the outdoor environment from human activities within buildings, we can derive it from the changes in energy balance fluxes between occupied and unoccupied buildings. Our derivation shows the difference between QEC and QF,B is attributable to a change in the storage heat flux induced by human activities (∆So-uo) (i.e., QF,B = QEC − ∆So-uo). Using building energy simulations (EnergyPlus) we calculate the energy balance fluxes for a simplified isolated building (obtaining QF,B, QEC, ∆So-uo) with different occupancy states. The non-negligible differences in diurnal patterns between QF,B and QEC caused by thermal storage (e.g. hourly QF,B to QEC ratios vary between −2.72 and 5.13 within a year in Beijing, China). Negative QF,B can occur as human activities can reduce heat emission from building but are associated with a large storage heat flux. Building operations (e.g., open windows, use of HVAC system) modify the QF,B by affecting not only QEC but also the ∆So-uo diurnal profile. Air temperature and solar radiation are critical meteorological factors explaining day-to-day variability of QF,B. Our new approach could be used to provide data for future parameterisations of both anthropogenic heat flux and storage heat fluxes from buildings. It is evident that storage heat fluxes in cities may also be impacted by occupant behaviour.

Item Type	Article
URI	https://reading-clone.eprints-hosting.org/id/eprint/102940
Identification Number/DOI	10.5194/acp-22-4721-2022
Refereed	No
Divisions	Science > School of the Built Environment > Energy and Environmental Engineering group Science > School of the Built Environment > Urban Living group
Publisher	Copernicus Publications
Download/View statistics	View download statistics for this item