Vertika Srivastav | Whole Building Simulation | CEPT University
Whole Building Simulation Final Report
Vertika Srivastav | PT501016 | CEPT University
Guide: Ar. Neeraj Kapoor Kalpakrit Sustainable Pvt. Ltd., New Delhi
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Vertika Srivastav | Whole Building Simulation | CEPT University
Table of Contents Executive Summary ................................................................................................................................ 3 Introduction ............................................................................................................................................ 4 Energy Analysis Methodology ............................................................................................................... 4 Computer Model............................................................................................................................. 4 About the Building .......................................................................................................................... 4 Building Area Program .................................................................................................................... 5 Climate Analysis & Passive Design Potential......................................................................................... 6 Climate Analysis .............................................................................................................................. 6 Passive Design Potential ................................................................................................................. 8 Shading & Daylight Analysis ................................................................................................................ 10 Shading Analysis............................................................................................................................ 10 Daylight Analysis ........................................................................................................................... 11 Prescriptive Method ..................................................................................................................... 11 Baseline Daylight Analysis using Lightstanza ................................................................................ 12 ECBC Baseline ....................................................................................................................................... 15 Learnings from ECBC 2017 ............................................................................................................ 15 Results of ECBC Baseline ............................................................................................................... 16 Elimination Parametrics ....................................................................................................................... 17 Isolated Measure Analysis ................................................................................................................... 18 Energy Conservation Measures ........................................................................................................... 20 Wall ............................................................................................................................................... 20 Roof ............................................................................................................................................... 21 Window ......................................................................................................................................... 22 Lighting Power Density ................................................................................................................. 22 HVAC System................................................................................................................................. 23 Shading Device .............................................................................................................................. 24 Summary of Setting Up the Baseline & Proposed Models ................................................................. 24 Integrated Design Opportunity ............................................................................................................ 25 Appendix............................................................................................................................................... 26 Energy Model Input ...................................................................................................................... 26 Schedules ...................................................................................................................................... 28 Utility Tariff Schedule.................................................................................................................... 30 Additional Daylight Analysis ......................................................................................................... 31
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Vertika Srivastav | Whole Building Simulation | CEPT University
Executive Summary The Energy Conservation Building Code (ECBC) was developed by the Govt. of India for new commercial buildings. ECBC sets minimum energy standards for commercial buildings having a connected load of 100kW or contract demand of 120 KVA and above. While the Central Government has powers under the EC Act 2001, the state governments have the flexibility to modify the code to suit local or regional needs and notify them. Presently, the code is in voluntary phase of implementation. About 22 states are at various stages of mandating ECBC, wherein most of building construction activities are happening across the country. According to UNDP-GEF Report, the annual energy consumption of a ECBC compliant institute building is 117 kWh/m2/year for composite climate. The building given is located in Delhi. The building has an area of nearly 5600 sq.m. The baseline annual energy consumption is 124 kWh/m2/year with 162 unmet hours. A building is considered in the composite climate of Delhi, which is a G+2 structure. The building is an institutional building with a few office spaces on the top floor. The methodology used for optimizing the building is: An energy model developed using Design Builder (Energy Plus). Different spaces had different operational schedules as per ECBC 2017, which were assigned to them. All the baseline values for mandatory ECBC requirements were assigned to the model. Baseline simulation was run. Further to understand the building loads and how they are affect by various other parameters, the elimination parametrics was run. Equating the different components of the building to zero. The elimination parametric was done in regular intervals to understand how the optimum U Value for some building cases be considered. After the elimination parametric was run, Energy Conservation Measures (ECMs) were selected in order to order to further optimize the ECBC compliant building. Different loads were studied and cost analysis for each ECM was done. As per the analysis of the energy model, it can be inferred that: Envelop insulation savings are up to 2 kWh/m2, when compared to the ECBC baseline model. Wall insulation helps in saving about Rs. 27 per m2, while Roof insulation helps in saving Rs. 61 per m2. Efficient HVAC system with high EER helps in reducing the cooling consumption. Cooling System is the most crucial aspect of the building, which can help achieve maximum savings. Reduction in energy consumption can also be reduced by reducing the lighting power density of the various spaces.
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Vertika Srivastav | Whole Building Simulation | CEPT University
Introduction The purpose of this exercise was to apply an integrated approach of Energy Conservation Building Code (ECBC) to all the systems that are a part of a building and help in reducing the energy consumption with compromising with the services that should be provided to occupants and their thermal comfort. The main objectives of this exercise were to: 1. Use climate analysis and assess passive design strategies 2. Optimize daylighting without changing the floorplan and building layout but by adding different shading devices 3. Understand ECBC, develop an energy model and simulate, which is ECBC compliant for composite climate conditions. 4. Explore energy conservation measures (ECM) that reduce internal and external loads through passive and active measures for composite climate. 5. Explore the impact of relevant ECMs on system sizing for capital cost reduction and energy performance.
Energy Analysis Methodology Computer Model This analysis utilizes Design Builder that runs on EnergyPlus engine. It is a whole building energy simulation program that engineers, architects, and researchers use to model both energy consumption—for heating, cooling, ventilation, lighting and plug and process loads—and water use in buildings. Its development is funded by the U.S. Department of Energy’s (DOE) Building Technologies Office (BTO). About the Building The building is a G+2 structure located in Delhi. The building is classified as an Institutional Building under the Building Typologies for ECBC2017 with an area of 5600 sq.m. The first two floors serve as college space while the top floor is a bank setup area for the training of the students. The building is functional from 9am to 6pm, five days a week, Saturday and Sunday is off. The building has a north facing entrance and had both conditioned & unconditioned spaces. The classrooms, faculty rooms, server room and labs are conditioned spaces which have split AC units of a CoP of 3.1while the AHU Room, corridor and courtyard spaces are naturally ventilated. The building is assumed to be ECBC compliant and further Energy Conservation Measures (ECMs) are devised in order to optimize the building further. The building is divided into various thermal zones a per the ECBCs Whole Building simulation method under the criterion: HVAC Thermal Zones.
Figure 1 Different thermal zones of the building
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Vertika Srivastav | Whole Building Simulation | CEPT University
Building Area Program DESIGN BRIEF / CHECK LIST - 1000 STUDENTS NO
1 2 3 4 5
USAGE GROUND FLOOR 60 SEATER CLASSROOMS 30 SETAER CLASSROOMS LAB H.O.D CABINS WITH FACULTY ROOM SERVER ROOM
ROOM NOS
TOTAL AREA (Sq.M.)
%
6 1 1 2 1
1683 554 60 121 185 30
33 4 7 11 2
6
FOOD COURT (UTENSIL WASH& HANDWASH AREA)
1
670
40
7 8 9 10 11
F.C PANTRY ELECTRICAL ROOM STORE ROOM A.H.U ROOM TOILETS
1 1 1 1 2
45 18 10 54 90
3 1 1 3 5
1 2 3 4 5 6 7
FIRST FLOOR 60 SEATER CLASSROOMS LAB/CLASS MODEL LABS ELECTRICAL ROOM DATA ROOM LIBRARY TOILETS
7 2 1 1 1 1 2
2120 647 242 184 18 11 305 90
31 11 9 1 1 14 4
1800 462 120 35 18 11 467 11 23
26 7 2 1 1 26 1 1
45 45
3 3
1 2 3 4 5 6 7 8
SECOND FLOOR 60 SEATER CLASSROOMS 30 SEATER CLASSROOMS MEETING ROOM ELECTRICAL ROOM DATA ROOM WORKSTATIONS FOR SUPP.STAFF& ADMIN DIRECTOR ROOM ADMINSTRATION ROOM (WITH 10 SUPP STAFF)
9 10
H.O.D CABINS TOILETS
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5 2 2 1 1 1 1 2 4 1
Vertika Srivastav | Whole Building Simulation | CEPT University
Climate Analysis & Passive Design Potential This section covers the climate analysis of New Delhi, India along with the passive design potential that can be considered for the composite climate in order to optimize the building and attain maximum savings.
Climate Analysis As per ECBC 2017, India is divided into five climatic zone, namely: Hot-Dry Warm-Humid Composite Temperate Cold The climate of Delhi is Composite, which means that the city experiences both high temperatures during summer (44˚C) and low temperatures during winter (5˚C) Figure 4 Climate Zone of Delhi
Temperature Range The average temperature for comfort zone is observed in March & October. Around the year, Delhi experiences maximum temperature of 44°C during May and minimum temperature of 5°C during January. The annual average temperature measures 25°C. Figure 3 Temperature Ranges for Delhi
Monthly Diurnal Averages The climate of Delhi has good diurnal variations throughout the year, whereas the variation is low for the monsoon months – July, August and September. The maximum diurnal variation achieved for summer months is 12°C in the month of May. Figure 4 Diurnal Averages for Delhi
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Vertika Srivastav | Whole Building Simulation | CEPT University
Ground Temperature
Figure 5 Ground Temperature Ranges
The ground temperature is 18°C - 27°C for April and May when ambient temperature goes up to 40°C and 44°C respectively. Ground based passive strategies favorable for only these two months. During winters when the ambient temperature is low 5°C – 10°C, the ground
Dry Bulb x Relative Humidity
Figure 6 Dry Bulb vs RH for Delhi
During the day, for the months April, May and June the humidity levels range between 20% to 40% with ambient temperature reaching 40°C or more. Thus, it will be favorable to use evaporative cooling. While, during the months July, August & September the humidity ranges between 60% to 80% with lower range of temperatures (20°C to 30°C).
Wind Analysis
Figure 7 Wind Wheel for Delhi
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The maximum wind speed is of 4 m/s, which comes from North, East & West direction. The average wind speed is of about 0.8m/s to 1m/s. Since, maximum classrooms are located in NW and NE direction, natural ventilation strategies can be worked out. The maximum percentage of time (20%) the wind flows from North – West Direction and 10% of wind flows from West an East direction. The temperature of wind coming from NW is between 21°C to 27°C with relative humidity ranging from 30% to 70%.
Vertika Srivastav | Whole Building Simulation | CEPT University
Comfort Hours & Operation Modes
Figure 8 Comfort hours using CARBSE Tool
Figure 9 various operation modes for Delhi
Using the CARBSE Tool for Comfort and Weather, the total number of comfort hours are determined which are 2731 out for total of 8760 hours in a year for 24hr naturally ventilated building. Since the building has conditoned classrooms the comfort hours would increase. Based on the climate of Delhi, following operations modes can be devised for the building system: For Jan, Feb, Mar, Nov: Preferably Natural Ventilation For Apr, Sep & Oct: Preferable to have mild cooling systems like evap. coolers For May, Jun, Jul: Active Cooling systems will be preferable. No heating is required for the winter months.
Passive Design Potential This section deals with the assessment of different type of passive strategies, which can be incorporated into the building to further optimize its performance.
Figure 10 various passive potential strategies for Delhi based on climate analysis
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Vertika Srivastav | Whole Building Simulation | CEPT University
Thermal Mass Internal thermal mass has the ability to help moderate the interior temperature swings of the building in spite of variable internal loads and fluctuating exterior temperatures. It can also be used as a heat storage component in a passive heating and cooling system. In a heating mode, the mass will absorb solar heat and internal gains during a sunny day and then reradiate that heat later when it is needed. As a summer cooling strategy, the mass can be cooled with night air so that it is ready to absorb heat during the following day. This strategy can be considered as a great opportunity for passive cooling along with night flushing for the building during the day. Trombe Wall A trombe wall, is a mass wall, with an airspace and an exterior glazing surface. The wall gathers solar heat through the glazing and a black or selective coating absorbs the heat. The heat moves slowly through the wall to help heat the interiors. Since, there are not much heating hours for composite climate this strategy cannot be implemented for the building. Also, during summers this strategy will heat up the building and increase the mechanical cooling loads. Natural Ventilation As per the climate analysis, Delhi has many days favourable outside temperatures that can help condition the building. This strategy helps to reduce mechanical cooling loads. Natural ventilation system works well with an economiser cycle. Since the floor-to-floor height for the building is 3800mm, high ceiling could help in producing stack ventilation with clerestory windows. This strategy can be fan assisted as well for better results. Evaporative Cooling Evaporative cooling is an adiabatic process in which warm dry air takes on moisture, lowering its temperature in the process (direct evaporative cooling). Indirect evaporative cooling can lower the air temperature by using a heat exchanger between evaporative cooled air and the building supply air. A combined direct/indirect evaporative cooler extends the design conditions under which evaporative cooling can sufficiently meet space conditioning requirements. Geothermal Cooling In case of Delhi, geothermal cooling might be a good strategy for cooling spaces during peak summer months. At a depth of 4m gives low temperatures as compared to the ambient temperature. The temperature varies from 20째C to 25째C (Figure 5 Ground Temperature Ranges) for April and May when the ambient temperatures range from 40째C to 45째C. But this might not be feasible on site and would add to a lot of additional cost with high payback period. Maintenance may also be an issue. Shading Device The baseline model of the ECBC compliant building does not take into account the shading devices, thus devices such as fins, overhangs & louvers can be considered. These help to reduce the direct solar radiation falling over the window and further reduce the heat gains inside the building. This also will help in attaining visual comfort of the occupants.
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Vertika Srivastav | Whole Building Simulation | CEPT University
Shading & Daylight Analysis This sections deals with the analysis and design of the shading device that can be incorporated into the design in order to minimize the heat gain through the windows. Another aspect that is covered in this section is the daylight analysis if the building. Various daylight metrics such as the Annual Sun Exposure (ASE), Daylight Autonomy (DA), Spatial Daylight Autonomy (sDA), Useful Daylight Index (UDI) and Average Illuminance, are explored for optimizing the daylight into the space and reducing the loads on artificial lighting systems.
Shading Analysis The building contains different types of windows orientated on different directions. Shaded hours were analysed using shading masks for 28°Nin order to understand the window design and proposed the shading devices accordingly. Fig. 11 shows different shading masks for different window types. Based on the masks from fig. 11, table 1 contains the summary of unshaded hours.
W1 on NW façade
W1 on NE façade
W1 on SE façade
W1 on SW façade
W1 on SE façade
W2 on SW façade
W2 on SE façade
W3 on SE façade
W3 on SE façade
L on NW façade
(Food court)
Figure 11 Shading masks for different windows on different orientations
Table 1 Unshaded Hours summary for all window types
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(750mm Overhang)
Vertika Srivastav | Whole Building Simulation | CEPT University
Daylight Analysis Daylighting is the controlled admission of natural light, direct sunlight, and diffused-skylight into a building to reduce electric lighting and saving energy. Beyond adding windows or skylights to a space the shading device is designed carefully to balance heat gain and loss, glare control, and variations in daylight availability. According to ECBC 2017, following are the requirements for daylighting: • Percentage of above grade floor area meeting the UDI requirement for Educational Building = 40% (for 90% of time) • Work plane Height = 0.8m • Schools should be analysed for 7 hours a day anytime between 8:00 AM to 5:00PM • Default Reflectance Values – (a) Wall = 50% (b) Floor = 20% (c) Ceiling = 70% For daylighting requirements, the ECBC prescriptive method is also followed. Lightstanza is a daylighting simulation tool, which works on the Radiance Engine. Light Foundry, LLC is a startup based in Boulder, Colorado that makes the software LightStanza, a web application for daylight simulations. It is a group talented engineers, scientists, environmentalists, artists, and architects passionate about daylight. Lightstanza is the tool employed too understand the daylight design for the given building.
Prescriptive Method as per ECBC 2017 Baseline – No Shading Device Head Height of the Window (in m)
Orientation
2.9
DEF
Window Width (in m)
Xm (distance perpendicular to fenestration)
Ym (distance parallel to fenestration)
North 3 93 8.7 94 South 2.5 81 7.2 82 East 1.8 134 5.2 135 West 1.5 113 4.3 114 Total daylight area in building meeting UDI requirement during 90% of the year (in sq.m.) Total Built up Area (in sq.m.) Useful Daylight Index (UDI) (in %)
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(X*Y sq.m.) Above grade area meeting the UDI requirement for 90% of the time in an year 817 593 704 495 2610 6306
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Proposed case for fenestration design Head Height of the Window (in m)
Orientation
DEF
2.9 Window Width (in m)
Xm (distance perpendicular to fenestration)
Ym (distance parallel to fenestration)
North 3.5 93 10.15 93.91 South 3 81 8.7 81.9 East 2.1 134 6.09 134.91 West 1.8 113 5.22 113.91 Total daylight area per floor meeting UDI requirement during 90% of the year (in sq.m.) Total Built up Area (in sq.m.) Useful Daylight Index (UDI) (in %)
(X *Y sq.m.) Above grade area meeting the UDI requirement for 90% of the time in an year 953 713 822 595 3082 6306 49
Baseline Daylight Analysis using Lightstanza Daylight Analysis for important spaces (Case w/o Shading Device) Orientation of the Window
Room Type
Daylight Autonomy
Spatial Daylight Autonomy
Annual Sun Exposure
Useful Daylight Index
Average Illuminance
18%
14%
7%
58%
210 lx
62%
70%
15%
88%
520 lx
54%
63%
3%
87%
410 lx
Scales Class
SW
01 & 14
Value Class 02 & 15
SE - SW
Value Class 03, 07 & 16
Value
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NE
Vertika Srivastav | Whole Building Simulation | CEPT University
Class 04 & 17
NE
Value
16%
16%
0%
60%
175 lx
25%
18%
0%
66%
295 lx
60%
66%
16%
89%
590 lx
58%
68%
13%
84%
751 lx
Class 05, 06, 11, 12 & 13
NW
Value Lab 02 – 56 Seater
SW - NW
Value Lab– 02 130 seater
Value
SW
Based on the analysis, all the important spaces had desirable DA and sDA, while few rooms were having high ASE values. After designing the shading device the rooms were high ASE were simulated. The shading device designed has two vertical fins, the right fin measures 0.9 m while, the right fin measures 0.6m m with a trapezoidal overhang in the form of light shelve. Design for Rooms facing South East & South West Façade
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Daylight Autonomy
Spatial Daylight Autonomy
Annual Sun Exposure
Useful Daylight Index
Average Illuminance
59%
67%
13%
89%
477 lx
50%
55%
3%
87%
355 lx
Vertika Srivastav | Whole Building Simulation | CEPT University
Design for Rooms facing South West and North West Faรงade Daylight Autonomy
Spatial Daylight Autonomy
Annual Sun Exposure
Useful Daylight Index
Average Illuminance
64%
14%
89%
544 lx
67%
0%
90%
531 lx
Base Case
60% Proposed Case
62%
Design for Rooms facing South West and South East Faรงade Daylight Autonomy
Spatial Daylight Autonomy
Annual Sun Exposure
Useful Daylight Index
Average Illuminance
48%
11%
82%
400 lx
55%
0%
84%
415 lx
Base Case
45% Proposed Case
50%
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Vertika Srivastav | Whole Building Simulation | CEPT University
ECBC Baseline Learning from ECBC 2017 Chapter 04 – Building Envelope ECBC specifies certain parameters such as U-Value of materials & SHGC of glass for the building compliance
Envelop Components External Wall (U-Value) Roof (U-Value) Glazing (U-Value) Maximum allowable SHGC Maximum SHGC for non-North Maximum SHGC North ≥ 15°N
0.40 W/m2K 0.33 W/m2K 3.0 W/m2K 0.9 0.2 0.5
Figure 12 Wall Assembly - ECBC Compliant
Figure 13 Roof Assembly - ECBC Compliant
Chapter 05 – Comfort Systems & Controls Minimum Requirements for Unit, Split & Packaged Air Conditioner Table 2 Minimum Requirements for Unit, Split & Packaged Air Conditioners
Cooling Capacity (kWr) ≤ 10.5 >10.5
Water Cooled NA 3.3 EER
Air Cooled BEE 3 Star 2.8 EER
Chapter 06 – Lighting & Controls The ECBC suggests two prescriptive requirements by which the building LPD can be allocated for a building. 1. Building Area Method 2. Space Function Method As per the building area method, the prescriptive requirement of Interior Lighting Power Density (LPD) for Educational Buildings is 11.2 W/m2. As per the space function method, the prescriptive requirements of interior LPD for different space types are:
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Vertika Srivastav | Whole Building Simulation | CEPT University
Table 3 Lighting Power Density for different space types
Space Type Restrooms Storage Conference/Meeting Rooms Electrical/Mechanical Rooms Banking Activity Open Plan Classrooms Labs Library (Reading Area) Stairway Corridor
Lighting Power Density (LPD) 7.7 W/m2 6.8 W/m2 11.5 W/m2 7.1 W/m2 12.6 W/m2 10 W/m2 13.8 W/m2 15.1 W/m2 10 W/m2 5.5 W/m2 7.1 W/m2
Figure 15 Energy Model in Design Builder
Results of ECBC Baseline
Graph 1 End Use breakdown of ECBC Baseline
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The graph shows the different end-uses of the baseline building. Cooling accounts for the maximum consumption in the building. Mechanical Ventilation (Fans) are the second highest energy consumers, while the equipment and lighting are low as compared to the others. By changing the cooling system shows the maximum potential of optimizing the energy efficiency of the building. Maximum savings can be achieved by optimizing the HVAC system into the building. For the baseline, split AC with mechanical ventilation has be considered with 2.8 EER. The baseline model achieves an Energy Performance Index (EPI) of 124 kWh/m2/year, with 162 hours. 103 TR system sizing.
Vertika Srivastav | Whole Building Simulation | CEPT University
Elimination Parametrics To understand the behaviour of the building in terms of loads elimination parametrics were carried out. To determine which variables have the greatest impact on the building’s heating, cooling, and total energy consumption, basic components of the building loads were zeroed out (near to zero). Building Component Wall (W/sq.m.) Roof (W/sq.m.) Window (W/sq.m.) Lighting Power Density (W/sq.m.) ACH Occupant Density (people/sq.m.) Equipment Power Density (W/m2)
ECBC Compliance Value for Elimination 0.4 0.014 0.3 0.016 U = 0.27 0.01 (both U and SHGC) SHGC = 0.27 Using Space Function 0.01 Method Min. = 3 | Max. = 6 0 Different for various 0 spaces 10 W/m2
End Use for Elimination Parametrics EP8-NoCoolHeat
Elimination Parametric
EP7-VentAir0 EP6-PeopleGain0 EP5-LightsGain0 EP4-WinCondGain0 EP3-WinRadGain0 EP2-RoofHtGain0 EP1-WallHtGain0 ECBC Baseline 0
20
40
60
80
100
120
kWh/m2 Cooling kWh/m2
Lighting (Interior) kWh/m2
Equipment (Interior) kWh/m2
Graph 2 Baseline End Use Breakdown
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Fans kWh/m2
140
Vertika Srivastav | Whole Building Simulation | CEPT University
Isolated Measure Analysis Wall Strategy ID WA001 WA002 WA003 WA004 WA005 WA006 WA007 WA008 WA009 WA010 WA011 WA012 WA013
Energy Conservation Measure Wall Assembly Incremental - 01 Wall Assembly Incremental - 02 Wall Assembly Incremental - 03 Wall Assembly Incremental - 04 Wall Assembly Incremental - 05 Wall Assembly Incremental - 06 Wall Assembly Incremental - 07 Wall Assembly Incremental - 08 Wall Assembly Incremental - 09 Wall Assembly Incremental - 10 Wall Assembly Incremental - 11 Wall Assembly Incremental - 12 Wall Assembly Incremental - 13
Measure Level U Value (W/sq.m) 2 1.5 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.014
EPI kWh/sq.m/yr 136 135 133 132 132 131 127 125 124 123 122 121 112
Unmet Hours Hours 184 184 181 179 174 175 179 173 162 158 145 142 131
Measure Level U Value (W/sq.m) 2 1.5 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.016
EPI kWh/sq.m/yr 133 130 128 127 127 126 125 125 125 124 123 122 110
Unmet Hours Hours 185 175 172 169 175 173 164 168 169 162 161 160 158
Measure Level U Value (W/sq.m) 3 2.5 1 1.5 1 0.5
EPI kWh/sq.m/yr 124 124 124 122 122 120
Unmet Hours Hours 162 165 164 158 158 147
Roof Strategy ID RF001 RF002 RF003 RF004 RF005 RF006 RF007 RF008 RF009 RF010 RF011 RF012 RF013
Energy Conservation Measure Roof Assembly Incremental - 01 Roof Assembly Incremental - 02 Roof Assembly Incremental - 03 Roof Assembly Incremental - 04 Roof Assembly Incremental - 05 Roof Assembly Incremental - 06 Roof Assembly Incremental - 07 Roof Assembly Incremental - 08 Roof Assembly Incremental - 09 Roof Assembly Incremental - 10 Roof Assembly Incremental - 11 Roof Assembly Incremental - 12 Roof Assembly Incremental - 13
Window Strategy ID WIN001 WIN002 WIN003 WIN004 WIN005 WIN006 18 | P a g e
Energy Conservation Measure Window U Value Incremental - 01 Window U Value Incremental - 02 Window U Value Incremental - 03 Window U Value Incremental - 04 Window U Value Incremental - 05 Window U Value Incremental - 06
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WIN007 WIN008 WIN009
Window SHGC Incremental - 01 Window SHGC Incremental - 02 Window SHGC Incremental - 03
SHGC 0.27 0.2 0.1
124 124 123
162 163 162
Measure Level
EPI
Unmet Hours
LPD (W/sq.m)
kWh/sq.m/yr
Hours
Space Function Method
124 121 120 97
162 177 176 112
Space Function Method
144 140 132 101
143 149 145 120
Measure Level
EPI
Unmet Hours
CoP 3.1 4.8 3.3 3.06
kWh/sq.m/yr 124 103 118 90 62
Hours 162 156 192 102 1500
EPI kWh/sq.m/yr 124 123
Unmet Hours Hours 162 152
Lighting Power Density Strategy ID
LPD001 LPD002 LPD003 LPD004 LPD005 LPD006 LPD007 LPD008
Energy Conservation Measure Lighting Controls ON LPD Incremental - 01 (ECBC) LPD Incremental - 02 (ECBCPlus) LPD Incremental - 03 (ECBCSuper) LPD Incremental - 04 (Zero) Lighting Controls OFF LPD Incremental - 01 (ECBC) LPD Incremental - 02 (ECBCPlus) LPD Incremental - 03 (ECBCSuper) LPD Incremental - 04 (Zero)
HVAC System Strategy ID HV001 HV002 HV003 HV004 HV005
Energy Conservation Measure Split AC + Mechanical Ventilation VRF + Heat Recovery & DOAS Unitary Cooling System Packaged DX System Evaporative Cooler
Shading Strategy ID SD001 SD002
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Energy Conservation Measure No Shading Device Shading Device
Measure Level NA NA
Vertika Srivastav | Whole Building Simulation | CEPT University
Energy Conservation Measures (ECMs) Wall Measure Objective Minimize heat transfer through cost-effective insulation choices. Measure Description The regression plot shows the linear relationship between EPI & the wall U value. As the U value of the wall the decreases, the EPI also reduces. The U value of 0.4 W/m2 is the baseline value, since more savings can be achieved, thus it is desirable to achieve a U value of 0.2 W/m2 for better energy savings. The thickness of insulation required would be 100mm.
Graph 3 Regression for Wall U Value
Wall - Savings in Energy & Cost 350
314
300
140
122
124
kWh/sq.m.
200 150
106
100 50 0 2
13
38
50
51
129
141
153
168
80 60 40
62
20 0
1.5
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
U Value Savings (Rs/sq.m.)
Total Energy (kWh/sq.m)
Graph 4 Energy Savings & Cost savings for wall
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100
179
0.1
0.014
Rs./sq.m.
120
250
0
160
Vertika Srivastav | Whole Building Simulation | CEPT University
Roof Measure Objective Minimize heat transfer through cost-effective insulation choices. Measure Description The regression plot shows the linear relationship between EPI & the roof U value. As the U value of the wall the decreases, the EPI also reduces, but not much variation is seen as compared to the wall. The U value of 0.3 W/m2 is the baseline value, since not much savings in EPI can be achieved but the cost savings are more as compared to the baseline value, thus it is desirable to achieve a U value of 0.2 W/m2. The thickness of insulation required would be 100mm.
Graph 5 Regression for roof u values
Roof - Savings in Energy & Cost 300
124
271
124
120
250
100
200
80 150 100
58
64
59
77
86
91
112
95
121
60 40
59
35
50
20
0 0
0 2
1.5
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
U Value Savings (Rs/sqm)
Total Energy (kWh/sq.m)
Graph 6 Energy Savings & Cost savings for Roof
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0.1
0.016
Rs./Sq.m.
kWh/sq.m.
140
Vertika Srivastav | Whole Building Simulation | CEPT University
Window Measure Objective Manage heat gain, loss and proper daylight penetration inside the space through appropriate selection of glass Measure Description U values ranging from 0.5 W/m2 to 3 W/m2 have been simulated to see the impact on the building without compromising to the visual comfort of the occupants. Glass with 3 W/m2 as the U value is the highest value that can be used for composite climate. Thus no change in the U Value of glass is considered. Same as the ECBC Baseline. In case of SHGC, no change is seen, so the value is considered same as the baseline of 0.27.
Graph 7 Regression for Window U Value
Lighting Power Density Measure Objective Reduce electric lighting energy by using Efficient lighting fixtures. Measure Description The values from ECBCPlus, Super ECBC & Near to Zero LPD have been considered to understand the impact of the lighting loads. As compared to ECBC, savings can be achieved in ECBC plus. Reduction in EPI is also observed as well as increase in cost Rs./sqm.
Graph 8 Energy Savings & Cost savings for LPDs
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Vertika Srivastav | Whole Building Simulation | CEPT University
HVAC Systems Measure Objective Reduce energy use by selecting higher efficiency systems. Measure Description Various systems of different EERs have been simulated in order to increase the efficiency of cooling system and further reduce the unmet hours. Systems considered for the building based on the schedules and functioning are: Split AC (baseline), VRF + Heat Recovery + DOAS, Unitary DX, Packaged DX & Evaporative Cooler (Low Energy Cooling System. VRF system with a EER of 4.8 is selected for the building. HVAC System - EPI & Unmet Hours 62
Evaporative Cooler
1500 90 102
Packaged DX System
118 192
Unitary Cooling System
103
VRF + Heat Recovery & DOAS
186 124 162
Split AC + Mechanical Ventilation 0
200
400
600
800
Total Energy (kWh/sqm)
1000
1200
1400
1600
Unmet Hours
Graph 9 HVAC System - EPI and Unmet hours
Savings (Rs/sqm) Evaporative Cooler
796
Packaged DX System
425
Unitary Cooling System
131
VRF + Heat Recovery & DOAS
317
Split AC + Mechanical Ventilation
0 0
100
200
300
400
500
Rs./sqm. Graph 10 Cost savings for HVAC Systems
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600
700
800
900
Vertika Srivastav | Whole Building Simulation | CEPT University
Shading Device Measure Objective Minimize heat gain through exterior shading devices. Measure Description The baseline building does not contain any type of shading device. Thus, based on the shading mask and daylighting analysis, a shading device has been designed to optimize the performance of the building. This shading device contains two vertical fins, the left fin has a projection of 0.9m while the right fin has a projection of 0.6m along with a trapezoidal overhang acting as a light shelf. Shading Device 200
150
162 124
152
123
100
61
50 0
0 Total Energy (kWh/sqm)
Unmet Hours No Shading Device
Savings (Rs./sqm)
Shading Device
Graph 11 Shading Device - Energy Savings, Unmet hours & Cost Savings
Summary of setting up the Proposed and Baseline Building Models Building Geometry Solar Shading Zoning Requirement
Baseline Building Proposed Building Same as baseline building, no change in the geometry, No consideration for any Modelled using shading shading devices and site devices obstructions. Both proposed and baseline building models follow same thermal zoning.
Material Wall U Value of 0.4 W/m2, with U Value of 0.2 W/m2, with 50 mm thick insulation on 100 mm thick insulation on exterior walls exterior walls. 2 Roof U Value of 0.3 W/m , with U Value of 0.2 W/m2, with 75 mm thick insulation 100 mm thick insulation Window U Value = 3 W/m2 and SHGC = 0.27 Room Data Lighting Power Density Lighting power is determined Lighting power is determined based on ECBC mandatory based on ECBC Plus requirements mandatory requirements Equipment Power Density Both proposed and baseline building models have same equipment power of 10 3 W/m2 across all the rooms. HVAC System Split AC with EER of 2.8 VRF + Heat Recovery + DOAS with EER of 4.8 24 | P a g e
Vertika Srivastav | Whole Building Simulation | CEPT University
Integrated Design Opportunity When all the ECMs selected from the parametric analysis, following results were obtained: Energy Performance Index (EPI) Unmet Hours System Tonnage End Use Component Cooling Interior Lighting Interior Equipment Fans Total Demand End Use Component Annual Fixed Charge (Rs.160/kW/month) Energy Charge (@ Rs. 9.95/kWh) Subtotal Surcharge (8% of Subtotal) Total Energy Cost Total Energy Cost (Rs./m2)
Baseline Building
Proposed Building
124 kWh/m2/year
90 kWh/m2/year
162 106 TR
157 106 TR
317476 kWh 103243 kWh 49564 kWh 186743 kWh 657028 kWh
313292 kWh 89443 kWh 49564 kWh 25507 kWh 477548 kWh
359 kW
233 kW
Rs. 689280
Rs. 447360
Rs. 6779571
Rs. 4740777
Rs. 7468851 Rs. 597508 Rs. 8066359 Rs. 1523 per m2
Rs. 5188137 Rs. 415050 Rs. 5603187 Rs. 1058 per m2
Using the isolated measure analysis for various aspects of a building component, multiple bundles can be created and simulated to analyse the potential savings that can be achieved in an ECBC compliant building. Just by adding more insulation on the walls, roof; adding appropriate shading devices; reducing LPDs and changing HVAC system with a high EER more energy savings can be ensured.
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Vertika Srivastav | Whole Building Simulation | CEPT University
Appendix a. Energy Model Inputs Components
Units
Baseline Values
General Building Area
m2
Electricity Rate
INR/kWh
Electricity Demand Rate
INR/kW/month
Natural Gas Rate
INR/GJ
Building Schedules
-
Occupant Density
Classroom
0.67
Labs (56 seater)
0.46
Labs (130 seater)
1.06
Library
0.16
Meeting 1
0.53
Meeting 2
0.53
Meeting 3
0.53
Electrical room
0.00
Server room
0.00
Open office
0.15
Hod rooms
0.09
Faculty room
0.23
Minimum OA ventilation
5294.00 â‚š 9.95 â‚š 160.00 Add rows below for each spacetype as needed, or reference a table you have created on another sheet here
Classroom
5 l/per 0.6 l/m2
Labs
5 l/per 0.6 l/m2
Library
2.5 l/per 0.3 l/m2
Open office
5 l/per 0.6 l/m2
Meeting
5 l/per 0.6 l/m2
Lighting Interior lighting power density
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W/m2 AHU room
7.1
Classroom
13.7
Classroom-30
13.7
Library
10.0
Labs
15.1
Pantry
12.1
Food court
9.1
Store
6.8
Electrical room
7.1
Vertika Srivastav | Whole Building Simulation | CEPT University
Lighting Control Devices
Server room
7.1
Washroom
7.7
Open office
12.6
Faculty room
13.8
Hod rooms
13.8
Meeting 1
11.5
Meeting 2
11.5
Staircase
5.5
Corridors
7.1
-
90% of the light fittings shall have automated control devices. These devices will be manual on auto off type Lumianaires in daylight zones shall have manual or automated control All meeting rooms shall have occupancy sensors that will turn off lights within 15 min of occupant leaving the room
Internal Loads Equipment Loads
W/m2
10W/m2 for all spaces
Wall Assembly
W/m2K
0.4
Roof Assembly
W/m2K
0.33
Roof Assembly
SRI value
75.00
Above-grade wall assembly
W/m2K
0.40
Below-grade walls Insulation
R-value
-
Doors (opaque)
U-value
-
Window to Wall Area Ratio
%
20.00
Windows
U-value (Eff)
3.00
Windows
SHGC
Windows
VLT
Envelope
0.27 (non north), 0.5 (north) 0.27
Split AC CoP
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2.8
Vertika Srivastav | Whole Building Simulation | CEPT University
b. Schedules
Source 1 ECBC 2017
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Vertika Srivastav | Whole Building Simulation | CEPT University
Source 2 ECBC 2017
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Vertika Srivastav | Whole Building Simulation | CEPT University
c. Utility Tariff Schedule
Source 3 BSES Yamuna Power LTD.
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Vertika Srivastav | Whole Building Simulation | CEPT University
d. Additional Daylighting Analysis
Baseline Daylight Analysis Ground Floor
UDI = 40%
ASE = 11%
UDI = 57%
ASE = 6%
UDI = 62%
ASE = 18%
First Floor
Second Floor
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Vertika Srivastav | Whole Building Simulation | CEPT University
References Energy Analysis Report For Tier Development for Partial - Compliance with ECBC – Phase 1 By ClimateWorks® Foundation and Shakti: India Sustainable Energy Foundation Energy Conservation Building Code (ECBC) 2017 – Bureau of Energy Efficiency Minstry of Power, Govt. of India BSES Yamuna Private Limited – Tariff Order 2017-18 http://www.derc.gov.in/ordersPetitions/orders/Tariff/Tariff%20Order/Tariff%20Order%20 for%20FY%202017-18/BYPL%20Tariff%20Order%20FY%202017-18.pdf Design Builder V4.7.023 Google Sketchup V2016 Lightstanza - http://lightstanza.com/ MS Word 2013 MS Excel 2013 Teraplot – Tool for plotting graphs Plotly – Online tool for developing graphs https://plot.ly/create/
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