Building Envelope Optimization in Office Buildings
DEENBANDHU CHHOTU RAM UNIVERSITY OF SCIENCE & TECHNOLOGY MURTHAL (SONEPAT) Department of Architecture Faculty of Architecture, Urban & Town Planning
Abstract This dissertation aims to establish optimum building aspect ratio and WWR of offices buildings from thermal performance point of view in different climatic zones of India. The effects of five different building aspect ratios (2:1, 1.5:1, 1:1, 1:1.5 & 1:2) and five WWR (20%, 30%, 40%, 50% & 60%) for office building in five climatic zone in India: Composite Climate, Hot & Dry Climate, Warm & Humid, Temperate Climate & Cold Climate. The eQuest software of Dept. of energy, USA is used for thermal analysis. The total energy consumption is compared for all five aspect ratios and WWR to arrive at the optimum performance. The envelope is delineated as per prescriptive U-vales for walls, roof and glass as given in the ECBC.
II
Structure of Presentation Chapter 1 Introduction
1.1
1.1 Problem Statement
1.1
1.2 Aim and Objectives
1.1
1.3 Scope of the works
1.2
1.4 Methodology
1.2
1.5 Significance
1.3
Chapter 2 Literature review
2.1
2.1 Introduction
2.1
2.2 Published / works (Building Envelope & Window Wall Ratio)
2.1
Chapter 3 Research Design
3.1
3.1 Introduction
3.1
3.2 Weather data for building energy modeling
3.1
3.3 Building Form
3.2
3.4 Building Envelope
3.2
3.5 Simulation Methodology
3.5
3.6 Energy Simulation Tool –eQUEST
3.6
3.6 Modeling and Simulation Process
3.7
3.7 Modeling Tables
3.8
III
Chapter 4 Building Simulation Processes
4.1
4.1 Introduction
4.1
4.2 Building Model 3D View
4.1
Chapter 5 Simulation Results & Analysis
5.1
5.1 Introduction
5.1
5.2 Simulation Result for Major Five Climate Zone in India
5.1
5.3 Overall Comparison of Simulation Result for Each Climate Zone in India
5.6
Chapter 6 Final Conclusions
6.1
6.1 Introduction
6.1
6.2 Result Review for Major Five Climate Zone in India
6.1
6.3 Future Development
6.4
References
R.1
III
Chapter 1 Introduction 1.1
Problem Statement
Nowadays decisions regarding geometry, orientation, materials and construction methods of a building are made all at a time in the architectural design, but thought is not always given to how those choices may affect the buildings ultimate energy usage and the effect they may have on climate change. This dissertation aims to find the suitable building aspect ratio and WWR in five Climate Zones in India. To reduce the energy consumption of the built environment. With the help of the following Parameters•
Building aspect ratio
•
India Climate Zones in India
•
Properties of Material used for building envelope
•
Orientation of Building
•
WWR (Window Wall Ratio)
1.2
Aim and Objectives
The aim of this dissertations to find out the effective / optimum of Energy Performance Index (EPI) by parametric simulation of an office building aspect ratio (2:1, 1.5:1, 1:1, 1:1.5 & 1:2), WWR (20%, 30%, 40%, 50% & 60%) and five Climate Zones in India. •
To understand study the state of the art of energy consumption in office buildings
•
To understand the provision of ECBC, NBC and ASHRAE.
•
To areas energy performance parametric study changing Building Envelope, Orientation & WWR for five Climate Zones in India.
•
To compare energy performances of (EPI) different cases.
•
To optimize WWR & orientation for each climatic zone in India. 1.1
1.3
Scope of the works
•
Computer Simulation on eQuest energy Simulation software
•
Assumption for Building Form, aspect ratio of building, window design parametric, properties of Material use for envelop, LPD, Equipment Load & building footprint area
•
Only for air conditioned building
1.4
Methodology
In order various to study parameters that affects the building energy performance, the dissertation follows the methodology given in the flow chart •
Building aspect ratio (2:1, 1.5:1, 1:1, 1:1.5 & 1:2)
•
Orientation North - South
•
WWR (20%, 30%, 40%, 50% & 60%)
•
Climate Zones in India
•
ECBC Building Envelope
With the help of eQuest energy simulation software to Energy Performance Index for each case will be found and will analyses them with a graphical comparisons.
1.2
Figure 1.1: Methodology Analyses graphical comparison
1.5
Significance
With the help of overall analysis we are able to judge Energy Performance with the change of Building aspect ratio, WWR, ECBC Building Envelop and North-south orientation can make a comparison for each different climate zone in India form of Energy Performance Index. This analysis will help to validate the statement – ‘Building aspect ratio, Orientation of N-S and WWR affects energy performance of the Building’ up to a certain limit.
1.3
Chapter 2 Literature review 2.1
Introduction
The chapter aims to present comprehensive literature review on the subject “Building Envelope Optimization in Office Buildings�. For this purpose international journals, conference Preceding’s, books, reports and other relevant literature have been referred. 2.2
Published / works (Building Envelope & Window Wall Ratio)
2.2.1
The Effects of Form and Orientation on Energy Performance of Residential Buildings in Ghana (Koranteng and Abaitey 2010)
The form and orientation of a building can have an effect on energy performance. The difficulty has been to find the most energy efficient form-aspect ratio. In this paper, a volume with differ-ent aspect ratios has been used to investigate the effect on energy performance (cooling load). The volume used is of the same construction and an hourly dynamic simulation programme was used for the analysis. It was evident that the square form was the most energy efficient whiles elongated forms used much energy. However, since spaces could warm up when oriented to-wards the east and west, the authors further recommend a detailed look into the function of spaces in design schemes and the use of simulation for design alternatives.
2.1
Table 2.1: Result of the Effects of Form and Orientation on Energy Performance of Residential Buildings in Ghana
Building Envelop WWR
The effect of windows, doors, roofing, etc on cooling load was avoided through the use of solid walls with the same None conductance for all building elements. The construction for the building elements is a 20cm monolithic wall with plasterblock-plaster composition having a solar absorptance value of 0.80 and conductance of 10.933 w/m²°C
Climate
Building Form
1:1.0 = 4.0 x 4.0 Kumasi, Ghana 1:1.5 = 3.26 x 4.89
1:2.0 = 2.8284 x 5.6568
1:2.5 = 2.5298 x 6.3245
1:3.0 = 2.3094 x 6.9282
Orientation
Outcome
North angles(°)
Cooling Lowest loads cooling -2 -1 (kWh.m a ) loads (%)
0/180 90/270,
102.07 102.18
0.11
45/225 135/315 0/180, 90/270,
103.17 101.61 105.55
1.08 3.87
45/225 135/315
105.62 107.41
3.94 5.70
0/180 90/270 45/225 135/315 0/180, 90/270 45/225 135/315
104.60 110.70 110.81 114.72 108.80 122.55 116.74 116.89
5.83 5.94 9.67 12.64 7.30 7.44
0/180 90/270 45/225 135/315
113.56 123.10 123.28 130.48
8.40 8.56 14.9 2.2
2.2.2
The Effect of Building Aspect Ratio on Energy Efficiency: A Case Study for Multi-Unit Residential Buildings in Canada (McKeen and Fung 2014)
This paper examines the energy consumption of varying aspect ratio in multi-unit residential buildings in Canadian cities. The aspect ratio of a building is one of the most important determinants of energy efficiency. It defines the building surface area by which heat is transferred between the interior and exterior environment. It also defines the amount of building area that is subject to solar gain. The extent to which this can be beneficial or detrimental depends on the aspect ratio and climate. This paper evaluates the relationship between the geometry of buildings and location to identify a design vernacular for energy-efficient designs across Canada Table 2.2: Model simulation geometry Shape of the Buildings
Building Profile:
A
B
B 90°θ
C
C 90°θ
D
D 90°θ
E
E 90°θ
F
F 90°θ
G
G 90°θ
Aspect Ratio (X:Y)
1:1
1.3:1
1:1.3
1.5:1
1.5:1
2:1
1:2
2.7:1
1:2.7
3.2:1
1:3.2
4.2:1
1:4.2
Dimensions X
24.5
28.0
21.4
30.0
20.0
35.0
17.1
40.0
15.0
44.0
13.6
50.0
12.0
Dimension Y
24.5
21.4
28.0
20.0
30.0
17.1
35.0
15.0
13.6
44.0
12.0
Wall Surface Area
2987
3011
3048
3176
3353
Glazing Area (% of exterior surface)
36%
36%
36%
36%
36%
Glazing Area
1075
1084
1097
1143
1207
South facing Surface Area
747
South Facing Surface (% of exterior surface)
25%
853
652
914
610
1067
521
40.0
1219
m m
3780
m2
36%
36%
-
1264
1361
m2
3511
457
50.0
Unit
1341
415
1524
366 m2
28%
22%
30%
20%
34%
16%
36%
14%
38%
12%
40%
10%
-
2.3
Table 2.3: Model simulation parameters
Table 2.4: Air infiltration rates
Envelope
Component
Description
Exterior Wall Aluminum and Glass Spandrel with batt insulation, metal frame
Roof
Built up roof, polyurethane insulation
Glazing
Floor: HVAC Component Terminal
Description Fan Coil Unit (four pipe) Heating Set Point: 20 °C
Cooling Plant
Centrifugal Hermetic Chiller Fuel Source: Electricity Boiler (natural draft) Fuel Source: Natural Gas
Ventilation:
7.5 L/s per person (~0.4 L/s per m2) Internal Load and Schedule
People Density: 200 m2/p Weekday Schedule:
50 Pa
ASHRAE “Leaky”
3.00
2.40
5 pa 0.510
0.6
ASHRAE “Average”
1.50
1.20
0.255
ASHRAE “Tight”
0.50
0.40
0.085
Average MURB in Canada
3.76
3.01
0.638
0.155
0.6
Selected for simulation
1.18
0.94
0.200
Table 2.5: Average annual heating and cooling degree days in Canadian cities (1971–2000)
-
0.3
0.1
-
Climatic Attributes Heating Degree Days Cooling Degree Days Climatic Region
Thermostat
Heating Plant Supply
75 Pa
Emissivity
0.364
Earth contact with insulated Ground Floor footings Double pane, Low emissivity with argon gas (Glass Type Code: 2642) Solar Heat Gain Coefficient.: 0.75, Solar Transmittance: 0.54 Concrete slab (150 mm)
Air Tightness Reference
U Value (W/m2K)
Infiltration Rate L/(s·m2) at
Vancouver
Calgary
Toronto
Montreal
Halifax
2926
4948
4066
4575
4367
44
44
252
235
104
wet, cool
dry, very cold
moderately wet, cold
moderately wet, cold
wet and cold
Cooling Set Point: 25.6 °C Autosized between 150 and 299 tons Coefficient of performance: 4.6 Autosized Efficiency: 80%
-
Equipment Load: 7.0 W/m2 Lighting Load: 10.8 W/m2 Return at: 4 PM Leave at: 9 AM
2.4
Unit
MW H) (GJ)
(GJ) %
(GJ) %
MW H) (GJ)
(GJ) % (GJ) %
MW H) (GJ)
(GJ) % (GJ) %
MW H) (GJ)
(GJ) % (GJ) %
MW H) (GJ)
(GJ) % (GJ) %
Table 2.6: Model simulation results: total annual energy consumption. REC, relative Shape of the Buildings
Building Profile: Aspect Ratio (X:Y)
G 90°θ 1:4.2
F 90°θ 1:3.2
E 90°θ
D 90°θ
C 90°θ
B 90°θ
A
B
1:2.7
1:2
1.5:1
1:1.3
1:1
1.3:1
C 1.5:1
D
E
F
2:1
2.7:1
3.2:1
G
Unit
4.2:1
Montreal Cooling Consumption
133.6 481.1
127.0 457.0
119.3 429.5
113.3 408.0
107.8 388.2
104.7 377.0
103.2 371.5
101.5 365.5
100.5 361.7
94.6 340.7
94.9 341.6
97.2 349.9
98.6 355.1
(MWH) (GJ)
Heating Consumption
1554
1461
1389
1315
1236
1213
1198
1188
1195
1243
1286
1355
1416
(GJ)
REC
29.7
21.9
15.9
9.8
3.2
1.2
0.0
-0.9
-0.2
3.7
7.3
13.1
18.2
%
Combined Energy Consumption
2035
1918
1818
1723
1624
1590
1569
1553
1557
1584
1628
1705
1771
(GJ)
REC
29.6
22.2
15.8
9.8
3.5
1.3
0.0
-1.0
-0.80
0.9
3.7
8.7
12.9
%
Vancouver Cooling Consumption
41.2 148.5
39.1 140.8
36.5 131.5
34.4 124.0
32.9 118.6
32.0 115.4
31.5 113.4
31.2 112.2
30.9 111.3
30.6 340.7
30.6 110.2
31.1 112.1
31.1 111.8
(MWH) (GJ)
Heating Consumption
911
836
775
722
672
659
641
637
637
637
664
746
793
(GJ)
42.1
30.4
20.8
12.6
4.8
2.7
0.0
-0.9
-0.7
-0.7
3.5
16.3
23.7
%
1060
977
907
846
791
775
775
749
748
774
807
858
905
(GJ)
REC Combined Energy Consumption REC Halifax Cooling Consumption
40.4
29.5
20.1
12.1
4.8
2.7
0.0
-0.7
-0.9
2.5
6.9
13.7
19.9
%
48.0 172.9
46.3 166.7
43.4 156.4
41.2 148.4
38.6 139.1
37.6 135.4
37.3 134.2
36.9 132.9
36.5 131.5
36.2 130.2
36.1 129.9
36.7 132.2
36.6 131.7
(MWH) (GJ)
Heating Consumption
1492
1381
1315
1236
1163
1139
1128
1120
1127
1171
1216
1282
1365
(GJ)
32.2
22.4
16.6
9.6
3.1
1.0
0.0
-0.7
-0.1
3.8
7.8
13.7
21.0
%
1665
1547
1471
1384
1302
1274
1262
1253
1259
1302
1346
1415
1496
(GJ)
REC Combined Energy Consumption REC Calgary Cooling Consumption
31.9
22.6
16.6
9.7
3.1
1.0
0.0
-0.7
-0.3
3.1
6.6
12.1
18.5
%
75.8 272.7
72.1 259.7
67.6 243.2
63.8 229.6
60.3 217.0
58.5 210.7
57.5 207.1
56.3 202.8
55.3 199.2
54.8 197.2
54.8 197.3
55.8 201.0
56.4 203.0
(MWH) (GJ)
Heating Consumption
1748
1534
1450
1366
1281
1254
1235
1221
1226
1270
1318
1387
1560
(GJ)
41.6
24.3
17.5
10.6
3.8
1.6
0.0
-1.1
-0.7
2.9
6.8
12.4
26.3
%
2021
1794
1694
1595
1498
1465
1442
1424
1425
1467
1516
1588
1763
(GJ)
REC Combined Energy Consumption REC Toronto Cooling Consumption
40.1
24.4
17.5
10.6
3.9
1.6
0.0
-1.2
-1.2
1.8
5.1
10.2
22.3
%
116.9 421.0
111.5 401.2
104.1 374.8
99.9 359.8
96.0 345.8
93.6 337.1
92.9 334.6
91.9 330.7
91.0 327.5
90.5 325.9
89.4 321.7
91.3 328.5
91.1 328.1
(MWH) (GJ)
Heating Consumption
1428
1302
1230
1157
1087
1063
1056
1048
1054
1100
1143
1211
1308
(GJ)
35.2
23.4
16.5
9.6
3.0
0.7
0.0
-0.8
-0.2
4.1
8.2
14.7
23.9
%
1849
1705
1604
1517
1433
1400
1391
1378
1381
1425
1464
1540
1636
(GJ)
33.0
22.6
15.4
9.1
3.0
0.7
0.0
-0.9
-0.6
2.5
5.3
10.7
17.6
%
REC Combined Energy Consumption REC
2.5
Chapter 3 Research Design 3.1
Introduction
The chapter aims to present comprehensive Research Design on the scope of the project with reference of the followings•
Energy Conservation Building Code (BEE 2007)
•
National Building Code (BIS 2005)
•
National Building Code Draft (BIS 2011)
•
Handbook of Fundamental - American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE 90.1.ip.2010)
The purpose of using above standards are, the Indian code with reference of Indian Climatic conditions for various climate zones. In this chapter we are defining all the parameter which affects energy performance for a building for which we can make a standard modelling by putting those values which will help us to prepare a base model to compare with the variables like Building Aspect Ratio, WWR & Orientation for various climatic zones. And can take other aspects with a specific value with specific purpose. 3.2
Weather data for building energy modeling
Building energy models have been carried out for four cities, which represent four major climate zones of India, namely: •
Delhi (Composite Climate)
•
Jaisalmer (Hot & Dry Climate)
•
Chennai (Warm & Humid Climate)
•
Bangalore (Temperate Climate)
•
Guwahati (Clod Climate)
3.1
3.3
Building Form
Air conditioned rectilinear office building with an aspect ratio1.
Building aspect ratio 2:1
–
Building Foot Print Area – 56.00m. X 28.00m. X 3.6 m.
2.
Building aspect ratio 1.5:1 –
Building Foot Print Area – 48.46m. X 32.30m. X 3.6 m.
3.
Building aspect ratio 1:1
–
Building Foot Print Area – 39.60m. X 39.60m. X 3.6 m.
4.
Building aspect ratio 1:1.5 –
Building Foot Print Area – 32.30m. X 48.46m. X 3.6 m.
5.
Building aspect ratio 1:2
Building Foot Print Area – 28.00m. X 56.00m. X 3.6 m.
•
Simulation for typical floor plan from a Mid-rise office building.
•
Window design is restricted to a rectangular shape and will be in uniform size.
•
Orientation
•
WWR
3.4
Building Envelope
–
The building envelope refers to the exterior façade, and is comprised of opaque components and fenestration systems. Opaque components include walls, roofs, slabs on grade (in touch with ground), basement walls, and opaque doors. Fenestration systems include windows, skylights, ventilators, and doors that are more than one-half glazed. The envelope protects the building’s interior and occupants from the weather conditions and shields them from other external factors e.g. noise, air pollution, etc. 3.2
Table 3.1: Table representing Opaque Wall Assembly U-Factor and Insulation R-value Requirements
Table 3.2: Table representing Roof Assembly U-Factor and Insulation R-value Requirements Other Building Types (Daytime)
Other Building Types (Daytime) Maximum U-factor of the overall assembly (W/m2·K)
Minimum R-value of insulation alone (m2·K/W)
Composite
U-0.440
R-2.10
Hot and Dry
U-0.440
R-2.10
Warm and Humid
U-0.440
R-2.10
Moderate
U-0.440
R-2.10
Cold
U-0.352
R-2.35
Climate Zone
Composite Hot and Dry Warm and Humid Moderate Cold
Table 3.3: Table representing Vertical Fenestration U-factor (W/m2•K) and SHGC Requirements Climate Composite Hot and Dry Warm and Humid Moderate Cold
Maximum U-factor 3.3 3.3 3.3 6.9 3.3
WWR≤40% Maximum SHGC 0.25 0.25 0.25 0.4 0.51
Table 3.5: Table representing HVAC Systems Category
Nonresidential
Area & Nos. of Floor
4 or 5 floors or less than 7,500 m² or 5 floors or less and 7,500–15,000 m²
Code
RHFS
System type
Central cooling plant with constant volume AHU for each zone
Fan control
Constant volume air handler for each zone
Cooling type
Chilled water
Heating type
Electric resistance
Table 3.7: Table representing Interior Lighting Power- Building Area Method Building Area Type Office
LPD (W/m2) 10.8
Maximum U-factor of the overall assembly (W/m2·K) U-0.409 U-0.409 U-0.409 U-0.409 U-0.409
Climate Zone
Minimum R-value of insulation alone (m2·K/W) R-2.1 R-2.1 R-2.1 R-2.1 R-2.1
Table 3.4: Table representing Minimum Visual Light Transmission Light Transmission Requirements 40% <WWR≤60% Maximum SHGC 0.2 0.2 0.2 0.3 0.51
Window Wall Ratio
Minimum VLT
0 - 0.3
0.27
0.31-0.4
0.2
0.41-0.5
0.16
0.51-0.6
0.13
Table 3.6: Table representing Suggested Chiller Specifications (ECBC-2007, HVAC) Equipment Class *Centrifugal Water Cooled Chiller < 530 W (<150 tons)
Minimum COP 5.8
Minimum IPLV 6.09
Test Standard ARI 550/590-1998
Table 3.8: Table representing Acceptable Occupant Densities, Receptacle Power Densities, and Service Hot Water Consumption
Building Type
Occupancy Density Sq.Ft./Person (Btu/h . ft2)
Receptacle Power Density Watts/Sq.Ft. (Btu/h . ft2)
Service Hot Water Quantities Btu/h. Person
Office 275 (0.84) 0.75 (2.56) 175 The occupancy densities, receptacle power densities, and service hot water consumption values are from ASHRAE Standard 90.1-1989 and addenda. Values are in square feet of conditioned floor area per person. Heat generation in Btu per person per hour is 230 sensible and 190 latent. Figures in parenthesis are equivalent Btu per hour per square foot. Values are in Watts per square foot of conditioned floor area. Figures in parenthesis are equivalent Btu per hour per square foot. These values are the minimum acceptable. If other Process loads are not input (such as for computers, cooking, refrigeration, etc.), it is recommended that receptacle power densities be increased until total process energy consumption is equivalent to 25% of the total. Values are in Btu per person per hour.
3.3
Table 3.9: Table representing Office Occupancy ASHRAE Specified Schedule for Office Building
Hour of Day (Time)
Schedule for Occupancy Percent of Maximum Load
Schedule for Lighting Receptacle Percent of Maximum Load
Schedule for HVAC System
Schedule for Service Hot Water Percent of Maximum Load
Schedule for Elevator Percent of Maximum Load
Wk
Sat
Sun
Wk
Sat
Sun
Wk
Sat
Sun
Wk
Sat
Sun
Wk
Sat
Sun
1 (12-1 am)
0
0
0
5
5
5
Off
Off
Off
5
5
4
0
0
0
2 (1-2 am)
0
0
0
5
5
5
Off
Off
Off
5
5
4
0
0
0
3 (2-3 am)
0
0
0
5
5
5
Off
Off
Off
5
5
4
0
0
0
4 (3-4 am)
0
0
0
5
5
5
Off
Off
Off
5
5
4
0
0
0
5 (4-5 am)
0
0
0
5
5
5
Off
Off
Off
5
5
4
0
0
0
6 (5-6 am)
0
0
0
10
5
5
Off
Off
Off
8
8
7
0
0
0
7 (6-7 am)
10
10
5
10
10
5
On
On
Off
7
7
4
0
0
0
8 (7-8 am)
20
10
5
30
10
5
On
On
Off
19
11
4
35
16
0
9 (8-9 am)
95
30
5
90
30
5
On
On
Off
35
15
4
69
14
0
10 (9-10 am)
95
30
5
90
30
5
On
On
Off
38
21
4
43
21
0
11 (10-11 am)
95
30
5
90
30
5
On
On
Off
39
19
4
37
18
0
12 (11-12 pm)
95
30
5
90
30
5
On
On
Off
47
23
6
43
25
0
13 (12-1 pm)
50
10
5
80
15
5
On
On
Off
57
20
6
58
21
0
14 (1-2 pm)
95
10
5
90
15
5
On
On
Off
54
19
9
48
13
0
15 (2-3 pm)
95
10
5
90
15
5
On
On
Off
34
15
6
37
8
0
16 (3-4 pm)
95
10
5
90
15
5
On
On
Off
33
12
4
37
4
0
17 (4-5 pm)
95
10
5
90
15
5
On
On
Off
44
14
4
46
5
0
18 (5-6 pm)
30
5
5
50
5
5
On
On
Off
26
7
4
62
6
0
19 (6-7 pm)
10
5
0
30
5
5
On
Off
Off
21
7
4
20
0
0
20 (7-8 pm)
10
0
0
30
5
5
On
Off
Off
15
7
4
12
0
0
21 (8-9 pm)
10
0
0
20
5
5
On
Off
Off
17
7
4
4
0
0
22 (9-10 pm)
10
0
0
20
5
5
On
Off
Off
8
9
7
4
0
0
23 (10-11 pm)
5
0
0
10
5
5
Off
Off
Off
5
5
4
0
0
0
24 (11-12 am)
5
0
0
5
5
5
Off
Off
Off
5
5
4
0
0
0
920
200
60
1040
280
120
1600
1200
0
537
256
113
555
151
0
Total/Day Total/Week
48.60 hours
56.00 hours
92.00 hours
30.54 hours
29.26 hours
Total/Year 2534 hours 2920 hours 4797 hours 1592 hours 1526 hours Wk = Weekday Schedules for occupancy, lighting, receptacle, HVAC system, and service hot water are from ASHRAE Standard 90.1-1989 and addendums, except that 5% emergency lighting has been added for all off hours. Elevator schedules, except for restaurants, are from the U.S. Department of Energy Standard Evaluation Techniques except changed to 0% when occupancy is 0%.These values may be used only if actual schedules are not known.
3.4
3.5
Simulation Methodology
Energy modeling software consists of a thermal calculation engine to predict the annual energy use of the building. As shown in Figure 3.1, building description defines the building geometry, layout, constructions, operating schedules, internal loads, HVAC systems, and local weather data. The simulation manager then performs an hourly simulation by calculating the building loads and the system requirements to meet the desired building conditions. The purpose of using above standards are, the Indian code with reference of Indian Climatic conditions for various climate zones. In this chapter we are defining all the parameter which affects energy performance for a building for which we can make a standard modelling by putting those values which will help us to prepare a base model to compare with the variables like Building Aspect Ratio, WWR & Orientation for various climatic zones. And can take other aspects with a specific value with specific purpose.
Figure 3.1: Diagram of Energy Modeling Loads 3.5
3.6
Energy Simulation Tool – eQUEST
eQUEST uses the DOE 2.2 Building energy simulation engine. It has the ability to explicitly model all of the following: •
8,760 hours per year
•
Hourly variations in occupancy, lighting power, miscellaneous equipment power, thermostat set-points, and HVAC system operation, defined separately for each day of the week and holidays
•
Thermal mass effects
•
Part-load performance curves for mechanical Equipment
•
Capacity and efficiency correction curves for mechanical heating and cooling equipment
eQUEST was designed to allow you to perform detailed analysis of today’s state-of-the-art building design technologies using today’s most sophisticated building energy use simulation techniques but without requiring extensive experience in the "art" of building performance modeling
It is supported as a part of the Energy Design Resources program which is funded by California utility customers and administered by Pacific Gas and Electric Company, San Diego Gas & Electric, and Southern California Edison, under the auspices of the California Public Utilities Commission. The basecase building is simulated with actual orientation and again after rotating the entire Building by 90, 180 & 270 Degrees and then averaging the results to get the Base-case Energy consumption.
Figure 3.2: eQUEST Logo
3.6
3.6
Modeling and Simulation Process
Each of the envelope and equipment efficiency cases was then simulated twice, once with no appliances and once with the use of appliances. This was done to understand the variation in energy consumption (appliances and AC) due to the appliancesâ&#x20AC;&#x2122; loads. The policy impacts and penetration of ECBC under various projection scenarios has been explained in the methodology of future projections. The following figure shows the building energy modelling run chart for the study: Building aspect ratio
Figure 3.3: Building Energy Modelling Run chart 3.7
3.7
Modeling Tables
3.7.1
Model Case - 1 (Composite Climate) - New Delhi Parameters
Value
Parameters
Value
Location- New Delhi
3.7.2
Model Case - 2 (Hot & Dry Climate) – Jaisalmer Parameters
Area (Sq.ft)
Table 3.10: Model Description for Composite Climate (New Delhi) Latitude
28°32'17.76"N
Longitude
77° 9'12.07"E
Elevation (ft.)
Composite Model Geometry
Building aspect ratio Dimension (ft.)
2:1 = 184’ x 92’ 1.5:1 = 159’ x 106’ 1:1 = 130’ x 130’ 1:1.5 = 106’ x 159’ 1:2 = 92’ x 184’
Floor to floor height (m)
3.6
Number of floors
G+4
20%, 30%, 40%, 50% & 60% Envelop Materials
Roof U value (W/m 2-K) Wall U value
Building aspect ratio Total Conditioned Space
867
Climate Type
WWR
Building aspect ratio Floor plate Area
(W/m 2-K)
0.409
2:1 = 16928 1.5:1 = 16854 1:1 = 16900 1:1.5 = 16854 1:2 = 16928 2:1 = 84640 1.5:1 = 84270 1:1 = 84500 1:1.5 = 84270 1:2 = 84640
Frames, Doors & Dividers Material
Aluminum
Frame width (cm)
1.3
Value
Parameters
Location- Jaisalmer Area (Sq.ft) Table 3.11: Model Description for Hot & Dry Climate (Jaisalmar) Latitude
26°54'33.34"N
Building aspect ratio Floor plate Area
Longitude
70°54'38.01"E
Building aspect ratio Total Conditioned Space
Elevation (ft.)
817
Climate Type
Hot & Dry
Building aspect ratio Dimension(ft.)
N/S degree
Glazing Glass U value (W/m2-K)
3.30
Glass SHGC
0.25 & 0.20
Glass VLT
0.27, 0.20, 0.16 & 0.13
2:1 = 184’ x 92’ 1.5:1 = 159’ x 106’ 1:1 = 130’ x 130’ 1:1.5 = 106’ x 159’ 1:2 = 92’ x 184’
Floor to floor height (m)
3.6
Number of floors
G+4
WWR
20%, 30%, 40%, 50% & 60% Envelop Materials
Roof U value (W/m 2-K)
0.409
Wall U value (W/m 2-K)
0.440
HVAC System
Material
Aluminum
Frame width (cm)
1.3
Orientation
N/S degree Glazing
Glass U value (W/m2-K)
0.25 & 0.20
Glass SHGC
0.27, 0.20, 0.16 & 0.13 0.13
Glass VLT
Internal Loads
Central cooling plant with constant volume AHU
Lighting (W/sq. m)
Equipment (W/sq. m)
7.5
Chiller COP
Constant volume air handler for each floor 5.8
Occupancy (sq. m/person)
14
Cooling type Heating type
Chilled water Electric Resistance
Fan Control
2:1 = 84640 1.5:1 = 84270 1:1 = 84500 1:1.5 = 84270 1:2 = 84640
0.440 Internal Loads
System Type
2:1 = 16928 1.5:1 = 16854 1:1 = 16900 1:1.5 = 16854 1:2 = 16928
Frames, Doors & Dividers
Model Geometry
Orientation
Value
10.8 System Type
Fan Control
HVAC System Central cooling plant with constant volume AHU
Chiller COP
Constant volume air handler for each floor 5.8
Cooling type Heating type
Chilled water Electric Resistance
Lighting (W/sq. m)
10.8
Equipment (W/sq. m)
7.5
Occupancy (sq. m/person)
14
3.8
3.7.3
Model Case - 3 (Warm & Humid) - Chennai
3.7.4
Model Case - 4 (Temperate Climate) – Bangalore
Table 3.12: Model Description for Warm & Humid (Chennai) Parameters
Value
Parameters
Location- Chennai
Value
12°58'47.46"N
Building aspect ratio Floor plate Area
Longitude
80°15'1.26"E
Building aspect ratio Total Conditioned Space
23
Climate Type
Warm & Humid Model Geometry
Building aspect ratio Dimension(ft.)
2:1 = 184’ x 92’ 1.5:1 = 159’ x 106’ 1:1 = 130’ x 130’ 1:1.5 = 106’ x 159’ 1:2 = 92’ x 184’
Floor to floor height (m)
3.6
Number of floors
G+4
WWR
20%, 30%, 40%, 50% & 60% Envelop Materials
Roof U value (W/m 2-K)
0.409
Wall U value (W/m 2-K)
0.440
Parameters
Area (Sq.ft)
Latitude
Elevation (ft.)
Table 3.13: Model Description for Temperate Climate (Bangalore)
2:1 = 16928 1.5:1 = 16854 1:1 = 16900 1:1.5 = 16854 1:2 = 16928 2:1 = 84640 1.5:1 = 84270 1:1 = 84500 1:1.5 = 84270 1:2 = 84640
Frames, Doors & Dividers Material
Aluminum
Frame width (cm)
1.3
Value
N/S degree Glazing
Glass U value (W/m2-K)
3.30
Glass SHGC
0.25 & 0.20
Glass VLT
0.27, 0.20, 0.16 & 0.13
Area (Sq.ft)
HVAC System Central cooling plant with constant volume AHU
12°57'45.01"N
Building aspect ratio Floor plate Area
Longitude
77°34'37.47"E
Building aspect ratio Total Conditioned Space
Elevation (ft.)
2970
Climate Type
Temperate Climate Model Geometry 2:1 = 184’ x 92’ 1.5:1 = 159’ x 106’ 1:1 = 130’ x 130’ 1:1.5 = 106’ x 159’ 1:2 = 92’ x 184’
Floor to floor height (m)
3.6
Number of floors
G+4
WWR
20%, 30%, 40%, 50% & 60% Envelop Materials
Roof U value (W/m 2-K)
0.409
Wall U value (W/m 2-K)
0.440
10.8
System Type
Fan Control
Constant volume air handler for each floor
Equipment (W/sq. m)
7.5
Chiller COP
5.8
Occupancy (sq. m/person)
14
Cooling type Heating type
Chilled water Electric Resistance
2:1 = 84640 1.5:1 = 84270 1:1 = 84500 1:1.5 = 84270 1:2 = 84640
Frames, Doors & Dividers Material
Aluminum
Frame width (cm)
1.3
Orientation
N/S degree Glazing
Glass U value (W/m2-K)
6.90
Glass SHGC
0.40 & 0.30
Glass VLT
0.27, 0.20, 0.16 & 0.13 Internal Loads
Lighting (W/sq. m)
Fan Control
2:1 = 16928 1.5:1 = 16854 1:1 = 16900 1:1.5 = 16854 1:2 = 16928
Latitude
Internal Loads System Type
Value
Location- Bangalore
Building aspect ratio Dimension(ft.)
Orientation
Parameters
HVAC System Central cooling plant with constant volume AHU
Lighting (W/sq. m)
10.8
Constant volume air handler for each floor
Equipment (W/sq. m)
7.5
Chiller COP
5.8
Occupancy (sq. m/person)
14
Cooling type Heating type
Chilled water Electric Resistance
3.9
3.7.5
Model Case - 5 (Cold Climate) - Guwahati Table 3.12: Model Description for Cold Climate (Guwahati) Parameters
Value
Parameters
Value
Location- Guwahati
Area (Sq.ft)
Latitude
26° 7'33.55"N
Building aspect ratio Floor plate Area
Longitude
91°44'51.82"E
Building aspect ratio Total Conditioned Space
Elevation (ft.)
179
Climate Type
Composite Model Geometry
Building aspect ratio Dimension(ft.)
2:1 = 184’ x 92’ 1.5:1 = 159’ x 106’ 1:1 = 130’ x 130’ 1:1.5 = 106’ x 159’ 1:2 = 92’ x 184’
Floor to floor height (m)
3.6
Number of floors
G+4
WWR
20%, 30%, 40%, 50% & 60%
Envelop Materials Roof U value (W/m 2-K) 0.409 Wall U value (W/m 2-K)
2:1 = 16928 1.5:1 = 16854 1:1 = 16900 1:1.5 = 16854 1:2 = 16928 2:1 = 84640 1.5:1 = 84270 1:1 = 84500 1:1.5 = 84270 1:2 = 84640
Frames, Doors & Dividers Material
Aluminum
Frame width (in.)
1.3
Orientation
N/S degree Glazing
Glass U value (W/m2-K)
3.30
Glass SHGC Glass VLT
0.51 0.27, 0.20, 0.16 & 0.13
0.352 Internal Loads
System Type
HVAC System Central cooling plant with constant volume AHU
Lighting (W/sq. m)
10.8
Fan Control
Constant volume air handler for each floor
Equipment (W/sq. m)
7.5
Chiller COP
5.8
Occupancy (sq. m/person)
14
Cooling type Heating type
Chilled water Electric Resistance
3.10
Chapter 4 Building Simulation Processes 4.1
Introduction
The chapter aims to present comprehensive Building Model 3D View of the various Building aspect ratio and WWR Snapshots on the subject â&#x20AC;&#x153;Building Envelope Optimization in Office Buildingsâ&#x20AC;?. 4.2
Building Model 3D View
Figure 4.1: Building Model 3D View at Building aspect ratio of 2:1 & 20% WWR
Figure 4.2: Building Model 3D View at Building aspect ratio of 1.5:1 & 30% WWR
4.1
Figure 4.3: Building Model 3D View at Building aspect ratio of 1:1 & 40% WWR
Figure 4.4: Building Model 3D View at Building aspect ratio of 1:1.5 & 50% WWR
Figure 4.4: Building Model 3D View at Building aspect ratio of 1:2 & 60% WWR
4.1
Chapter 5 Simulation Results & Analysis 5.1
Introduction
The chapter aims to present comprehensive Simulation Results & Analysis on the subject “Building Envelope Optimization in Office Buildings”. 5.2
Simulation Result for Major Five Climate Zone in India
5.2.1
Simulation Result New Delhi
Table 5.1: Simulation Result for (Composite Climate) - New Delhi (in E.P.I.) Climate Zone
Composite Climate
Building aspect ratio City
Orientation
New Delhi
N.S
WWR 2:1
1.5:1
1:1
1:1.5
1:2
20%
100.95
100.35
100.72
102.04
102.37
30%
100.84
101.11
101.17
101.88
102.64
40%
110.54
110.53
111.06
111.66
112.54
50%
112.21
111.95
111.75
113.1
114.29
60%
109.73
109.67
110.37
111.51
112.36
Max.
Min.
% saving
114.29
100.35
12.20%
Max. Energy Consumption = 114.29 kWh/sq.m./year (At Building aspect ratio of 1:2 & 50% WWR) Min. Energy Consumption = 100.35 kWh/sq.m./year (At Building aspect ratio of 1.5:1 & 20% WWR)
ENERGY PERFORMANCE INDEX( KWH/SQ.M./YEAR)
Envelope Performance (Composite Climate) - New Delhi 120 115 110 105 100 95 90 2:1
1.5:1
1:1
1:1.5
1:2
BUILDING ASPECT RATIO WWR 20%
WWR 30%
WWR 40%
WWR 50%
WWR 60%
Figure 5.1: Envelop performance graph for (Composite Climate) - New Delhi (in E.P.I.)
5.1
5.2.2
Simulation Result Jaisalmer
Table 5.2: Simulation Result for (Hot & Dry Climate) – Jaisalmer (in E.P.I.) Climate Zone
Hot & Dry Climate
Building aspect ratio City
Orientation
Jaisalmer
N.S
WWR 2:1
1.5:1
1:1
1:1.5
1:2
20%
103.28
102.65
102.98
104.44
104.87
30%
103.21
103.47
103.48
104.28
105.19
40%
112.69
112.69
113.24
113.88
114.84
50%
114.34
114.04
113.88
115.31
116.49
60%
112.06
112.00
112.73
114.03
114.85
Max.
Min.
% saving
116.49
102.65
11.88%
Max. Energy Consumption = 116.49 kWh/sq.m./year (At Building aspect ratio of 1:2 & 50% WWR)
Min. Energy Consumption = 102.65 kWh/sq.m./year (At Building aspect ratio of 1.5:1 & 20% WWR)
ENERGY PERFORMANCE INDEX( KWH/SQ.M./YEAR)
Envelope Performance (Hot & Dry Climate) - Jaisalmer 120 115 110 105 100
95 2:1
1.5:1
1:1
1:1.5
1:2
BUILDING ASPECT RATIO WWR 20%
WWR 30%
WWR 40%
WWR 50%
WWR 60%
Figure 5.2: Envelop performance graph for (Hot & Dry Climate) – Jaisalmer (in E.P.I.)
5.2
5.2.3
Simulation Result Chennai
Table 5.3: Simulation Result for (Warm & Humid) - Chennai (in E.P.I.) Climate Zone
Warm & Humid Climate
Building aspect ratio City
Orientation
Chennai
WWR
N.S
2:1
1.5:1
1:1
1:1.5
1:2
20%
108.72
108.51
108.55
108.92
108.84
30%
107.30
107.47
107.37
107.62
107.81
40%
116.46
116.27
116.56
116.92
117.62
50%
117.80
117.43
117.04
118.03
118.97
60%
114.86
114.67
114.91
115.59
116.24
Max.
Min.
% saving
118.97
107.37
9.75%
Max. Energy Consumption = 118.97 kWh/sq.m./year (At Building aspect ratio of 1:2 & 50% WWR)
Min. Energy Consumption = 107.37 kWh/sq.m./year (At Building aspect ratio of 1:1 & 30% WWR)
ENERGY PERFORMANCE INDEX( KWH/SQ.M./YEAR)
Envelope Performance (Warm & Humid Climate) - Chennai 120
115 110 105 100 2:1
1.5:1
1:1
1:1.5
1:2
BUILDING ASPECT RATIO WWR 20%
WWR 30%
WWR 40%
WWR 50%
WWR 60%
Figure 5.3: Envelop performance graph for (Warm & Humid) Chennai (in E.P.I.)
5.3
5.2.4
Simulation Result Bangalore
Table 5.4: Simulation Result for (Temperate Climate) – Bangalore (in E.P.I.) Climate Zone
Temperate Climate
Building aspect ratio
City
Orientation
Bangalore
N.S
WWR 2:1
1.5:1
1:1
1:1.5
1:2
20%
95.19
95.06
95.22
95.90
95.81
30%
92.88
93.11
93.10
93.42
93.63
40%
99.72
99.75
99.97
100.47
101.37
50%
99.20
99.12
99.10
99.99
100.96
60%
98.94
96.01
96.63
97.39
98.02
Max.
Min.
% saving
101.37
92.88
8.38%
Max. Energy Consumption = 101.37 kWh/sq.m./year (At Building aspect ratio of 1:2 & 40% WWR)
Min. Energy Consumption = 92.88 kWh/sq.m./year (At Building aspect ratio of 2:1 & 30% WWR)
ENERGY PERFORMANCE INDEX( KWH/SQ.M./YEAR)
Envelope Performance (Temperate Climate) – Bangalore 104 102 100 98 96 94 92 90 88 2:1
1.5:1
1:1
1:1.5
1:2
BUILDING ASPECT RATIO WWR 20%
WWR 30%
WWR 40%
WWR 50%
WWR 60%
Figure 5.4: Envelop performance graph for (Temperate Climate) – Bangalore (in E.P.I.)
5.4
5.2.5
Simulation Result Guwahati
Table 5.5: Simulation Result for (Cold Climate) - Guwahati (in E.P.I.) Climate Zone
Cold Climate
Building aspect ratio City
Orientation
Guwahati
N.S
WWR 2:1
1.5:1
1:1
1:1.5
1:2
20%
100.74
100.62
100.72
101.17
101.08
30%
99.92
100.10
100.12
100.28
100.74
40%
109.91
109.83
110.22
110.77
111.98
50%
114.01
113.52
113.34
115.21
116.82
60%
112.38
112.40
112.84
114.45
115.81
Max.
Min.
% saving
116.82
99.92
14.47%
Max. Energy Consumption = 116.82 kWh/sq.m./year (At Building aspect ratio of 1:2 & 50% WWR)
Min. Energy Consumption = 92.92 kWh/sq.m./year (At Building aspect ratio of 2:1 & 30% WWR)
ENERGY PERFORMANCE INDEX( KWH/SQ.M./YEAR)
Envelope Performance (Cold Climate) Guwahati 120 115
110 105 100
95 90 2:1
1.5:1
1:1
1:1.5
1:2
BUILDING ASPECT RATIO WWR 20%
WWR 30%
WWR 40%
WWR 50%
WWR 60%
Figure 5.5: Envelop performance graph for (Cold Climate) Guwahati (in E.P.I.)
5.5
5.3
Overall Comparison of Simulation Result for Each Climate Zone in India
Table 5.6: Overall Comparison of Simulation result for each climate zone Building aspect ratio City
Composite New Delhi Climate
Orientation
N.S
WWR 2:1
1.5:1
1:1
1:1.5
1:2
20%
100.95
100.35
100.72
102.04
102.37
30%
100.84
101.11
101.17
101.88
102.64
40%
110.54
110.53
111.06
111.66
112.54
50%
112.21
111.95
111.75
113.1
114.29
60%
109.73
109.67
110.37
111.51
112.36
20%
103.28
102.65
102.98
104.44
104.87
30% Hot & Dry Jaisalmer Climate
Warm & Humid Climate
Chennai
Temperate Bangalore Climate
Cold Climate
Guwahati
N.S
N.S
N.S
N.S
40%
103.21
112.69
103.47
112.69
103.48
113.24
104.28
113.88
Max.
Min.
% saving
114.29
100.35
12.20%
% Savings Potential for each Climate Zone
105.19
114.84
50%
114.34
114.04
113.88
115.31
116.49
60%
112.06
112.00
112.73
114.03
114.85
20%
108.72
108.51
108.55
108.92
108.84
30%
107.30
107.47
107.37
107.62
107.81
40%
116.46
116.27
116.56
116.92
117.62
50%
117.80
117.43
117.04
118.03
118.97
60%
114.86
114.67
114.91
115.59
116.24
20%
95.19
95.06
95.22
95.9
95.81
30%
92.88
93.11
93.10
93.42
93.63
40%
99.72
99.75
99.97
100.47
101.37
50%
99.20
99.12
99.10
99.99
100.96
60%
98.94
96.01
96.63
97.39
98.02
20%
100.74
100.62
100.72
101.17
101.08
30%
99.92
100.10
100.12
100.28
100.74
40%
109.91
109.83
110.22
110.77
111.98
50%
114.01
113.52
113.34
115.21
116.82
60%
112.38
112.40
112.84
114.45
115.81
116.49
118.97
102.65
107.37
11.88%
9.75%
SAVING % BETWEEN LOWEST & HIGHEST ENERGY E.P.I.
Climate Zone
16 14
14.47 12.2
12
11.88 9.75
10
8.38
8
6 4 2 0 New Delhi
Jaisalmer
Chennai
Bangalore
Guwahati
MAJOR CLIMATE CITY IN INDIA
Figure 5.6: % Savings Potential for each Climate Zone in India 101.37
92.88
8.38%
116.82
99.92
14.47%
5.6
Chapter 6 Final Conclusions 6.1
Introduction
The chapter aims to present comprehensive Final Conclusions on the subject “Building Envelope Optimization in Office Buildings”. The next section presents the Result Review for Major Five Climate Zone in India and Final section presents the Future Development of the various Simulation Results & Analysis on the subject 6.2
Result Review for Major Five Climate Zone in India
6.2.1
Result Review New Delhi
•
True North-South orientation is the best orientation
•
By increasing WWR energy consumption is also increasing due to more heat gain in to the building through window.
•
Max. Energy Consumption = 114.29 kWh/sq.m./year (At Building aspect ratio of 1:2 & 50% WWR)
•
Min. Energy Consumption = 100.35 kWh/sq.m./year (At Building aspect ratio of 1.5:1 & 20% WWR)
•
In New Delhi, as per our results building aspect ratio 1.5:1 leads to least consumption among the other counterparts. But the pattern is consistent in 20% WWR case only.
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We can reduce 12.20% energy consumption by using at Building aspect ratio, WWR and orientation of North /South for New Delhi.
6.1
6.2.2
Result Review Jaisalmer
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True North-South orientation is the best orientation
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By increasing WWR energy consumption is also increasing due to more heat gain in to the building through window.
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Max. Energy Consumption = 116.49 kWh/sq.m./year (At Building aspect ratio of 1:2 & 50% WWR)
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Min. Energy Consumption = 102.65 kWh/sq.m./year (At Building aspect ratio of 1.5:1 & 20% WWR)
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In Jaisalmer, as per our results building aspect ratio 1.5:1 leads to least consumption among the other counterparts. But the pattern is consistent in 20% WWR case only.
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We can reduce 11.88% energy consumption by using at Building aspect ratio, WWR and orientation of North /South for Jaisalmer.
6.2.3
Result Review Chennai
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True North-South orientation is the best orientation
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By increasing WWR energy consumption is also increasing due to more heat gain in to the building through window.
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Max. Energy Consumption = 118.97 kWh/sq.m./year (At Building aspect ratio of 1:2 & 50% WWR)
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Min. Energy Consumption = 107.37 kWh/sq.m./year (At Building aspect ratio of 1:1 & 30% WWR)
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In Chennai, as per our results building aspect ratio 1:1 and 30% WWR becomes most efficient design.
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We can reduce 9.75% energy consumption by using at Building aspect ratio, WWR and orientation of North /South for Chennai.
6.2
6.2.4
Result Review Bangalore
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True North-South orientation is the best orientation
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By increasing WWR energy consumption is also increasing due to more heat gain in to the building through window.
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Max. Energy Consumption = 101.37 kWh/sq.m./year (At Building aspect ratio of 1:2 & 40% WWR)
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Min. Energy Consumption = 92.88 kWh/sq.m./year (At Building aspect ratio of 2:1 & 30% WWR)
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In Bangalore, as per our results building aspect ratio 2:1 and 30% WWR becomes most efficient design.
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We can reduce 8.38 energy consumption by using at Building aspect ratio, WWR and orientation of North /South for Bangalore.
6.2.5
Result Review Guwahati
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True North-South orientation is the best orientation
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By increasing WWR energy consumption is also increasing due to more heat gain in to the building through window.
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Max. Energy Consumption = 116.82 kWh/sq.m./year (At Building aspect ratio of 1:2 & 50% WWR)
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Min. Energy Consumption = 92.92 kWh/sq.m./year (At Building aspect ratio of 2:1 & 30% WWR)
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In Guwahati, as per our results building aspect ratio 2:1 and 30% WWR becomes most efficient design.
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We can reduce 14.47% energy consumption by using at Building aspect ratio, WWR and orientation of North /South for Guwahati.
6.3
6.3
Future Development
In the India, the environmental burden of buildings represents a problem that need to be alleviated. In order to fulfill with international agreements and commitments, the Government of India will be forced to set new rules regarding building energy consumption. As a first step In order to comply with the new regulations, architects should develop their design techniques, adopt more environmental strategies and finally increase their knowledge about the environment and buildings. As each building will be provided with limited amount of energy, architects will be forced to change many design decisions, concepts, elements and materials. On the other hand, mechanical and environmental engineers will have a major role in the design process as they will be studying how each decision architects take affects the building total energy consumption. Therefore, in order to provide the architects with a holistic approach of reducing thermal energy consumption in office buildings located in different climates, Finally, more research should be done on achieving a balance between reducing energy by the passive techniques and the user's visual and acoustical comfort. If done, this research would help architects and designers in taking the proper environmental design decisions that achieve users comfort in the built environment.
6.4
References •
BEE (2005) National Building Code, Bureau of Indian Standard, New Delhi.
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Energy Conservation Building Code (2009). Bureau of Energy Efficiency.
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ASHRAE Standard (2010). American Society of Heating, Refrigerating, and Air-Conditioning Engineers.
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http://www.sciencedirect.com/
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http://www.researchgate.net/publication
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Koranteng, C. and Abaitey, E. G. (2010)."The Effects of Form and Orientation on Energy Performance of Residential Buildings in Ghana", Journal of Science and Technology, vol. 30, pp. 01, http://www.ajol.info/index.php/just/article/download/53940/42487.
•
McKeen, P. and Fung, A. S. (2014)."The Effect of Building Aspect Ratio on Energy Efficiency: A Case Study for Multi-Unit Residential Buildings in Canada”, Building, vol. 04, pp. 336-354, http://www.mdpi.com/2075-5309/4/3/336.
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http://apps1.eere.energy.gov/buildings/energyplus/cfm/weather_data2.cfm/region=2_asia _wmo_region_2
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http://www.doe2.com/equest/
R.1