Page 67 - JCAU-5-2

Journal of Chinese
Architecture and Urbanism Cooling energy-saving mechanism

The load reduction rate of the envelope with good optimization.
performance at the corresponding time is lower than
that of the envelope with poor performance. From this Acknowledgments
microscopic distribution feature, it can be proven that None.
with the improvement of the thermal performance of
the envelope, the monthly and annual energy-saving Funding
rates of air conditioning temperature setpoint rise by This work is supported by the National Natural
1°C and decrease on a macroscopic basis.
(v) After the addition of internal heat source, the annual Science Foundation of China (No. 52108032) and the
Sichuan Science and Technology Research Program
cooling consumption of the four grades of envelope (No. 2022NSFSC1148).
increases significantly, but the annual relative energy-
saving rate is basically the same as before. The relative Conflict of interest
energy-saving rate of high-grade and top-grade
envelope is only slightly higher than that without The authors declare that they have no competing interests.
internal heat source, which is due to the same climatic
conditions, the increase of internal heat source does Author contributions
not significantly increase the number of hours of Conceptualization: Jianwu Xiong and Yin Zhang
air-conditioning, and the energy-saving mechanism Formal analysis: Jianwu Xiong
does not fundamentally change. After the addition Investigation: Jing Wu and Yin Zhang
of internal heat source, the annual absolute energy Methodology: Zexuan Tian and Yin Zhang
savings increases significantly, the performance Project Administration: Jianwu Xiong
of envelope is improved, and the energy savings is Software: Meng Han
increased by a greater degree, indicating that new Supervision: Yin Zhang
buildings with a large internal heat source have greater Validation: Meng Han and Zexuan Tian
energy-saving potential and higher absolute energy Writing – original draft: Jianwu Xiong and Yin Zhang
saving value by advocating to raise the temperature Writing – review and editing: Meng Han, Jing Wu, and
set-point of air conditioning. Zexuan Tian
In fact, building cooling energy consumption amounts Ethics approval and consent to participate
are influenced by many factors, such as building types
(residential, office, hotel, shopping mall, factory, etc.), since Not applicable.
the human behaviors or occupants’ habits vary widely in
those buildings, resulting in different timely internal heat Consent for publication
gains and dynamic load requirement changes for space Not applicable.
cooling. For another example, even for building thermal
grade of external envelopes, the age of the building may Availability of data
significantly impact practical heat transfer processes, since Climatic data for simulation are available on website:
the heat insulation performance gradually decays with https://www.energyplus.net/weather.
increasing years of usage, especially for those inserted
wall insulation layers in retrofitting old building with References
limited lifespan of usage. Besides, practical energy usage
amount depends on the types and thermal performance of Aryal, A., & Becerik-Gerber, B. (2018). Energy consequences of
Comfort-driven temperature setpoints in office buildings.
indoor cooling equipment and systems, such as air-source Energy and Buildings, 177:33-46.
heat pump, ground-source heat pump, and radiant air
conditioner. In practical engineering, the building energy- ASHREA. (2013). ANSI/ASHREA Standard 55-2013, Thermal
saving potential and rate could vary widely with different Environmental Conditions for Human Occupancy. Atlanta:
air-conditioning devices, benchmarks, and reference ASHREA.
systems, even in the same climatic zones. Although the Belazi, A., Ouldboukhitine, S. E., Chateauneuf, A., & Bouchair, A.
specific results obtained in typical cases may not meet (2019). Experimental and numerical study to evaluate the
all the different conditions, the analysis methods used in effect of thermostat settings on building energetic demands
this article are general and applicable to other occasions, during the heating and transition seasons. Applied Thermal
which can provide references for energy-saving potential Engineering, 152:35-51.
assessment for cooling system and building thermal design Feijó-Muñoz, J., González-Lezcano, R. A., Poza-Casado, I.,

Volume 5 Issue 2 (2023) 13 https://doi.org/10.36922/jcau.0877