Effect of electrochromic windows on energy consumption of high-rise office buildings in different climate regions of Iran

Windows are one of the weakest building components concerning high thermal losses. Traditional windows cannot adapt to external and internal environmental conditions. On the other hand, smart windows such as electrochromic (EC) windows do not emit greenhouse gases and adapt to environmental conditions and increase indoor environmental quality. The combination of EC windows and building integrated photovoltaic system (BIPV) is called photovoltachromic (PVC) windows. This paper aims to find optimal window to wall ratio (WWR) ranges of PVC windows in a high-rise office building model in four different cities in Iran. This paper uses several simulations to find the optimal WWR ranges of PVC windows using Radiance and EnergyPlus. First, the minimum acceptable WWR value in each climate condition was identified using several simulations without any optimization tools. Afterward, traditional windows were replaced with EC windows and results indicated that energy consumption of the building reduced up to 15.94%. In the next stage, BIPV was combined with EC windows, and results indicated that BIPV reduced energy consumption of the building up to 7.55%. Finally, simulation results showed that PVC windows reduced energy consumption of the building up to 16.31% in Kermanshah, 19.69% in Tehran, 18.59% in Yazd and 17.36% in Bandar Abbas. Also, the optimal WWR range of PVC windows in Kermanshah was 80-90%, while it was 70-80% in Tehran, Yazd and Bandar Abbas. Simulation results indicated that cooling degree days (CDD) of the site, where buildings were located, effected on the optimal WWR range of PVC windows in high-rise office buildings. An analytical approach was used to validate simulation results, and it showed that simulation results had 1.60-6.22% error.

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Concepts in the Design of Lateral-Load Systems in High Rise Buildings to Reduce Operational Energy Consumption

International Institute of Chemical, Biological & Environmental Engineering June 5-6, 2015 Istanbul (Turkey) ◽

10.15242/iicbe.c0615003 ◽

2015 ◽

Keyword(s):

Energy Consumption ◽

Lateral Load ◽

High Rise ◽

Operational Energy

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A STUDY ON THE ANNUAL VARIATION OF ENERGY CONSUMPTION IN OFFICE BUILDINGS

Journal of Environmental Engineering (Transactions of AIJ) ◽

10.3130/aije.72.81_1 ◽

2007 ◽

Vol 72 (615) ◽

pp. 81-87

Author(s):

Kazuhiko SAKAMOTO ◽

Saburo MURAKAWA ◽

Michimasa SHINOHARA ◽

Daisaku NISHINA ◽

Yoshiyuki UEMURA

Keyword(s):

Energy Consumption ◽

Annual Variation ◽

Office Buildings

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Research on the application of three-dimensional green in high-rise office buildings

3rd International Conference on Contemporary Problems in Architecture and Construction ◽

10.1049/cp.2011.1146 ◽

2011 ◽

Author(s):

Xu Yifang ◽

Li Aiji

Keyword(s):

Three Dimensional ◽

Office Buildings ◽

High Rise

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A Fundamental Study on the Development of New Energy Performance Index in Office Buildings

Energies ◽

10.3390/en14082064 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2064

Author(s):

Jin-Hee Kim ◽

Seong-Koo Son ◽

Gyeong-Seok Choi ◽

Young-Tag Kim ◽

Sung-Bum Kim ◽

...

Keyword(s):

Energy Consumption ◽

Energy Requirement ◽

Energy Performance ◽

Office Buildings ◽

Light Transmittance ◽

Wall Structure ◽

Fundamental Study ◽

Future Studies ◽

U Value ◽

The Impact

Recently, there have been significant concerns regarding excessive energy use in office buildings with a large window-to-wall ratio (WWR) because of the curtain wall structure. However, prior research has confirmed that the impact of the window area on energy consumption varies depending on building size. A newly proposed window-to-floor ratio (WFR) correlates better with energy consumption in the building. In this paper, we derived the correlation by analyzing a simulation using EnergyPlus, and the results are as follows. In the case of small buildings, the results of this study showed that the WWR and energy requirement increase proportionally, and the smaller the size is, the higher the energy sensitivity will be. However, results also confirmed that this correlation was not established for buildings approximately 3600 m2 or larger. Nevertheless, from analyzing the correlation between the WFR and the energy requirements, it could be deduced that energy required increased proportionally when the WFR was 0.1 or higher. On the other hand, the correlation between WWR, U-value, solar heat gain coefficient (SHGC), and material property values of windows had little effect on energy when the WWR was 20%, and the highest effect was seen at a WWR of 100%. Further, with an SHGC below 0.3, the energy requirement decreased with an increasing WWR, regardless of U-value. In addition, we confirmed the need for in-depth research on the impact of the windows’ U-value, SHGC, and WWR, and this will be verified through future studies. In future studies on window performance, U-value, SHGC, visible light transmittance (VLT), wall U-value as sensitivity variables, and correlation between WFR and building size will be examined.

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The Role of Wind on Double Skin Facades in High Rise Office Building

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.787.711 ◽

2013 ◽

Vol 787 ◽

pp. 711-716

Author(s):

Daryanto ◽

Eko Budihardjo ◽

Wahyu Setyabudi ◽

Gagoek Hardiman

Keyword(s):

Energy Conservation ◽

Building Envelope ◽

Office Buildings ◽

Thermal Discomfort ◽

High Rise ◽

Double Skin ◽

The Subject ◽

Air Conditioning Systems ◽

Double Skin Facades

There was an indication that high rise buildings in Jakarta was not designed based on energy conservation principles. The most important aspects of the high-rise buildings is energy saving technology located in the building envelope design. Building envelope with a full glass design functions for widening view and enhancing natural lights, even though but it is also increasing energy consumption and thermal discomfort due to the intensity of solar radiation in hot humid climates. During the current decade, the development of double building envelope type (Double Skin Façade: DSF) seemed more just to improve the aesthetics and the use of natural light, while the wind and thermal performance aspects were still lack of serious consideration. Those aspects will be chosen as the subject matter in this research. The research was aimed to investigate and compare the value of heat transfer in the building envelope of high-rise office buildings. Samples were taken from five DSF buildings, with closed and open cavity. CFD software is used for simulation of the five different models of DSF. The research proves that the high-rise office buildings as the research object in Jakarta do not apply energy conservation principle. The utilization of wind in the DSF cavity can reduce temperature and relieve the burden of air conditioning systems that is energy save. An important finding of the research is the need for ventilation in the design of a double skin at high-rise office buildings in the humid tropics.

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