NATIONAL UNIVERSITY OF SINGAPORE MSC. INTEGRATED SUSTAINABLE DESIGN AY 2017/2018
ISD5104: ENERGY AND ECOLOGY
A CASE STUDY ON REE TOWER IMPROVING ENERGY & ENVIRONMENTAL PERFORMANCE
TUTORS Professor Karel Kabele Professor Kua Harn Wei GROUP 1 Ian Matthew Yu Go Trinh Phuong Quan Nikita Sharma
A0163414M A0166426B A0166441H
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CONTENTS A. CURRENT LOCATION: HO CHI MINH CITY, VIETNAM A1. LOCATION A2. CLIMATE CONDITION B. REE TOWER- EXISTING SITUATION B1. BASIC INFORMATION B2. BUILDING DESCRIPTION B3. BUILDING DRAWINGS C. EXISTING ENERGY CONCEPT C1. EXTERNAL FINISHES C2. INTERNAL FINISHES WITH U VALUE C3. MECHENICAL SERVICES C4. ELECTRICAL SERVICES D. PROPOSED LOCATION: MARINA BAYS, SINGAPORE D1. LOCATION D2. CLIMATE CONDITION E. SWOT ANALYSIS F. PROPOSED NEW ENERGY CONCEPT F1. GENERAL PRINCIPLE FOR ENERGY EFFICIENCY F2. BUILDING ENVELOP F3. ORIENTATION ANALYSIS F4. FACADE STRUCTURE F5. CLADDING F6. NATURAL VENTILATION F7. AIR-CONDITIONING SYSTEM F8. ARTIFICIAL LIGHTING SYSTEM F9. NATURAL LIGHTING SYSTEM F10. ELECTRICAL SYSTEM F11. BIO-MASS PLANT SYSTEM F12. WATER SYSTEM F13. GREEN SPACES AND PLANTS F14. SEWAGE TREATMENT SYSTEM F15. ELEVATOR ENGERGY REGENERATION SYSTEM G. VISION G1. ENVIRONMENTAL IMPACT G2. RECOMMENDATIONS
HO CHI MINH CITY 10.8’ 106.6’ 3
A. CURRENT LOCATION: HO CHI MINH CITY, VIETNAM
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A1. Location 1. Location of Ho Chi Minh City 2. Isometric view 3. Satellite map of the Site location
REE tower is situated in
District 4, Ho Chi Minh City, Vietnam just 1 km from the Central Business
District. Ho Chi Minh City is a city in the south part of Vietnam. It is gov-
erned as a municipality and includes
a large rural area. It is the biggest city in Vietnam. About 6.2 million people live in the city. The city was formerly called “Saigon”, a name still used in
casual conversation. To its North and West is the Ben Nghé Canal. To its
East, Saigon River and to its South, Kênh te. It sits in a mass of land
surrounded by a system of rivers and canals.
A2. Climatic condition
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1. Solar chart, Wind rose and Temperature diagram 2. Photos represent the climatic condition of Ho Chi Minh City
Ho Chi Minh City, Vietnam
has a tropical climate, with an av-
erage humidity of 75%. The year is
divided into two distinct seasons. The rainy season, with an average rainfall of about 1,800 millimetres annually. The average temperature is 28 °C.
There are two main prevailing winds:
South-East in summer and Southwest in winter.
Average monthly sunshine reach-
es from 160 to 270 hours, average
humidity is 79.5%. While April has the highest average monthly tempera-
ture (30.5ÂşC), December is the lowest month (26ÂşC). From May to October the wet season occurs while July to
November the typhoon season can cause tropical storms.
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B. REE TOWER, EXISTING SITUATION REE tower is an office building located in District 4, Ho Chi Minh City, 1 km from the Central Business District. This was one of the first tall office building in District 4 and was putting on operation since 2009,
B1. Basic Information Site Area: 2047 sq.m
Total GFA: 32,289.50 sq.m
No. of floors: 3 basement car parking levels, ground floor, mezzanine level and twenty floors
B2. Building Description Structure: Reinforced Concrete Structure- with Columns at 7 meters C/C
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Building Height: 78.9 meters
Facade: Exterior Treated Glass Wall
Building Program: Commercial Office Building & Sublet to Tenants
Estimated Number of Users: 2000
1. View from the main facade and back facade 2. Elevations
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B3. Building drawings
The plan of the REE tower is
very simple with a concrete struc-
tural core placed in the back of the building. This kind of arrangement
will help to maximize the floor area for leasing and reduce the building cost.
The average span distance
between the two columns is 9 me-
ters. The floors are re-enfored con-
crete with the thickness of the slabs is 300mm. This kind of structure is the typical one of tall building in Typical Floor Plan
Vietnam.
Ground Floor Plan
Basement Floor Plan Section
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C. EXISTING ENERGY CONCEPT C1. External Finishes
Facade Description: Exterior treated glass wall of 33.18mm thickness with aluminum surround frame and acrylic paint Entrance : Granite tile Office Walls : Painted Floor : Screed concrete Ceiling : Acoustic tile and gypsum board suspended ceiling Windows : Powder coated aluminum frame
C2. Internal Finishes with ‘U’ Values:
Non-Transparent Walls: Painted: 1.94 W/mK Glazing: Glass wall- 33.18 mm thickness- Aluminum frames: 0.70 W/mK Windows: Powder coated aluminum frame: 0.70 W/mK Roof: RCC- untreated: 0.55 W/mK Ceiling: Acoustic tile & gypsum board suspended ceiling: 1.78 W/mK Underground Structure: RCC: 0.55 W/mK
C3. Mechanical Services:
Control: Air conditioning computerized building automation system with individual tenant control Capacity: 3 chillers; 350 cubic tons; 16 fan coil units per floor
C4. Electrical Services :
Back Up Power: 2 x 1600 KVA diesel generators Capability: 100% standby Lighting type: Parabolic fluorescent Lighting levels: 400 lux at desk height Power density: 50 VA / sq.m
1. Interior view from a typical floor 2. Isometric view of the typical floor revealing structure, material and finishes
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SINGAPORE 1.2’ 103.8’ 9
D. PROPOSED LOCATION: SINGAPORE D1. New location
• 12A Bay Front avenue
• 1 km to the Downtown core
• Near the Marina Bay MRT station • Area: 13400 sqm 1
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1. Location of the Singapore’s CBD 2. Satellite photos of Marina Bays
The proposed REE Tower will be situated in 12A Bay Front avenue 1 km to the Downtown core. The new location is within
walking distance from the Marina Bay MRT station. This is now an emply plot in the new central business district of Singapore.
The site has a great view to the Marina Bay while the oth-
er faces with the Garden by the bay. Connected well with a
good modern infrastructure, the site has a strategic place in
the Center of Singapore that perserved for the comercial and business activities.
D2. Singapore climate
Important Data: Max Temperature: ±30.5°C Min Temperature: ±24.5°C Min Temperature: ±26.5°C Relative Humidity: ±81%
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Northeast Monsoon Season(Decemberearly March)
PREVAILING WINDS
Northerly to north easterly winds
WEATHER FEATURES Early Northeast Monsoon (Wet Phase) continuous moderate to heavy rain, at times with 25-35 km/h winds in the first half of the season, usually from December to early January. Rapid development of afternoon and early evening showers.
Inter-monsoon Period(Late MarchMay)
Light and variable, interacting with land and sea breezes
Thunderstorms occur in the afternoon and early evening. Hot afternoons are common (maximum temperature above 32°C).
Southwest Monsoon Season(JuneSeptember)
South easterly to southerly
wind gusts of 40-80 km/h between the predawn hours and midday. Short duration showers/thunderstorms in the afternoon
Inter-monsoon Period(OctoberNovember)
Light and variable, interacting with land and sea breezes
Thunderstorms in the afternoon and early evening.
2 1. Climatic chart of Singapore 2. Photos of the nature, ecology and downtown Marina Bay
Singapore’s climate is characterized by
sodes in the Northeast Monsoon flow
inter-monsoonal periods. The North-
Afternoon and evening thunder-
two monsoon seasons separated by
east Monsoon occurs from December to early March, and the Southwest
Monsoon from June to September.
Monsoon surges, or strong wind epi-
bringing about major rainfall events.
storms caused by strong surface heating and by the sea breeze circulation that develops in the afternoon.
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E. SWOT ANALYSIS Strengths:
Facade: Glazing on 3 sides- North, East & West- Naturally lit building. View of the Marina Bay. Location: High-rise office building in CBD. Regular plying MRT & buses. Planning & Structure: Open plan. Easy to modify. Easy for future expansion. Revenue Generation: Maximum leasing capacity- Office & tenant space. Services: Service core planned on the South-East facade that receives minimum thermal heating. 3 tier underground parking facilities
Opportunities:
Improve connectivity: Connect by a jetty to the harbor. Renovation to an office complex: Skywalk to connect with other existing/ proposed buildings in the vicinity. Utilize renewable resources: Wind Energy: harness wind energy from the bay. Solar Energy: Equatorial sunlight to be used by solar & PV panels. Rainwater Harvesting Pits: receives abundant rainfall through the year. Biogas Plant: Generate electricity & act as District electric supply for neighboring buildings. Enhance MEPF services to be more sustainable and efficient.
Weaknesses:
Facade: Simple /Plain facade, not iconic. Heat: Tremendous thermal heat gain on West facade as lack of shading devices. Lack of Green Windows: Fixed windows, No natural ventilation. Direct light causes glare on computer screens. MEPF Systems: Obsolete. Building Materials: Not sustainable, Lack of insulation Open Areas: No microclimate generation & lack of social interactive areas.
Threats:
Facade: Not an iconic building & can be replaced easily. Location: Can cause Heat Island effect. Climatic Conditions: cannot be solely dependent on solar panels for electricity source- cloudy days may make it inefficient. Biomass Plant: could be a hassle to maintain and supervise by the office building.
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F. PROPOSED ENERGY CONCEPT F1. General Principle for Energy Efficiency
The following general principles for heating, cooling and electricity consumption enable energy efficient buildings in all climate zones: •Well insulated and airtight building envelope •Minimized thermal bridges
•Extensive use of daylighting
•Selection of simple systems to cover heating requirements •Selection of simple systems to cover cooling requirements •Energy efficient equipment
South-West Orientation (Original)
F2. Building Envelope
•16cm rigid mineral wool insulation is executed on the facades
•It has a high insulation value, stiff form and great resistance to mold development
•Causes muted effect on thermal bridging (between structural elements)
F3. Orientation
The Ecotect solar access analysis was conducted based on the twos
different orientation of the building. It is evidence in the fact that the SW orientation has a lower annual total radiation compared to the NE ori-
North-East Orientation (Isolation Analysis)
entation. This can be explained by the larger glazing surface facing with direct West sunlight in the afternoon.
3.5% Increase
South-West Orientation (Original)
North-East Orientation (Isolation Analysis)
Total radiation received- 10216.05 Wh
Total radiation received- 105757.03 Wh
F4. Facade Double facades in translucent cladding seal exteriors for energy efficiency while admitting natural light. In order to reduce the effect of solar radiation in the tropical region, a system of shading devices are attached to the West and South West of the building. The effectiveness of the shading systems are checked by Ecotect simulation by the two phases analysis. Firstly, the horizontal shading devices are places in each floor with the overhanging distance is 1.5 meters. This create a dramatic decline of total solar radiation effected the facades of the model to approximately 58%. Secondly, the vertical shading devides are places in each floors to create the aesthestic and architectural elements for the building. By this arrangement, the total solar radiation is reduced to 62.4%
REE Tower with Horizontal Shading Devices Total Radiation: 69976.6 Wh
REE Tower with Horizontal & Vertical Shading Devices Total Radiation: 63762.7 Wh
Reduction in radiation by 62.4 % 15
F5. Cladding Vector Foiltech ETRE Membrane, a light-weight, translucent cladding system that provides higher insulation and better weather-resistance than glass. ETRE foil systems also can be integrated with solar shading and typically self-clean in the rain.
F6. Ventilation • Leave interior slabs exposed (by eliminating dropped ceilings, for example) to help regulate interior temperatures and reduce reliance on mechanical heating and cooling. • Cooler nighttime air is absorbed by the structure to moderate the heat of the sun; conversely sunlight is absorbed during the day to moderate the evening chill. • Extensive use of LED lighting provides for long-term energy efficiency and an immediate reduction in building maintenance, as bulb changes and relamping is eliminated
S.No 1.
2.
Existing
Proposed
Natural Ventilation Windows- double glazed glass (38 mm)
Natural Ventilation Automated & openable windows • Triple glazed with (60mm thick glass) with airspace widths of 16mm b/w • low e- coating • Low heat transfers
Mechanical Ventilation
Mechanical Ventilation • Use of Displaced Ventilation
Fresh air supply & return air ducts in the false ceiling
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high efficiency cooling equipment
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increasing electricity-driven fan use
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reducing energy loss in air ductwork to and from a building central plant and due to pressure drops in air ducts.
F7. Air- conditioning S.No 1.
Existing Air conditioning systems •
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2.
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Proposed Air-conditioning systems Office & common areasHeat pump systems & cooling towers
Office and the Common Area of the building is air-conditioned by a central water chilled air-conditioning system. Tenant spaces are cooled by ceiling concealed duct type FCU’s (Fan Coil Units) complete CHW (chilled water) piping reticulation and FCU thermostat controller.
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Current temperature maintained within the building- 18°C ozone friendly refrigerant R134a and anti-bacterial chemicals in the water basin of the cooling tower.
3 Chiller Plants on the roof Decentralized Cooling System
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Tenant space- Floor level air supply vents & ceiling level hot air suctions.
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Provision of ceiling fans
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Proposed temperature maintained within the building23°C
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Using the same refrigerant
2 Chiller Plants on the roof WILO Pumps to limit the amount of water entering the chillers. Cold Water pumped into the building absorbs the heat from the rooms 17
1. Flow chart of the aircons system
F8. ARTIFICIAL LIGHTING SYSTEMS S.No. 1.
Existing Lighting systems
ARTIFICIAL LIGHTING •
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Proposed Lighting systems
ARTIFICIAL LIGHTING High efficiency light fixtures using LED’s standard office spaceslighting power density of 0.7 watts/sq. ft. Task/Ambient approach- ceilingmounted suspended fixtures and task lighting at each workstation.
Average standard illumination in the Development ranges from 300 lux to 500 lux at desk level depending on the area where the lights are located.
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Common area lighting will be controlled by the Management Office and operated in accordance with normal business hours.
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Lights are dimmed in response to daylight sensors and switched on in response to infra-red occupancy detectors.
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In the private offices, there is a combined infra-red detector and an ultrasonic detector to control on/off. False detections by the highly sensitive ultrasonic device, capable of detecting slight keyboard activity, are avoided
2. Optimizing Natural Light with Artificial light
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F9. NATURAL LIGHTING AND SHADING SYSTEM S.No. 1.
Existing
Proposed
• Average standard illumination in the Development ranges from 300 lux to 500 lux at desk level depending on the area where the lights are located. • Common area lighting will be controlled by the Management Office and operated in accordance with normal business hours.
1. Incident light- daylight entering the building
• BMS operates exterior window shading, but the room occupants have complete control over the openable windows. • natural ventilation is intended to provide users with a sense of control over their own comfort conditions as well as to reduce the cooling load when used by the occupants. • Smart Blinds: angle changes with respect to the angle of the sun- anti- glare effect
2. Existing shading system
3. Proposed shading sytem
Increase 90% shading system The effectiveness of the shading systems are checked by Ecotect simulation. Light rays reflection on the shading devices are measured to accquire the neces-
sary amount of lighting on the working surface based on different angles of the sun in a day.
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F10. ELECTRICAL SYSTEM S.No
Existing
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Power design capacity- 50 VA per sqm (lighting system, FCU- fan coil units) Supply- 3 phase, 50 Hz electrical power supply
Proposed Phase 1 of electricity generated on site: PV panels connected to District electric poles- : 40 % Phase 2: Electricity generated with Biogas plants : 30% Phase 3: Electricity generated by wind turbines (at night) and fed to direct grid (future use) : 10%
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Back up supply: 2 caterpillar generators – diesel
Back up supply : solar panels collectors
Solar Panel Calculation Louvers: 162.5 sq m X 20 Floors= 3250 sq.m Roof Structure: 600 sq.m On surface Parking str: 600 sq.m Total sq.m of solar panels : 4500 s.m= 1660 Panels=3634 kWh per year
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1. Electricity generated by wind turbines 2. Solar panels collectors on car park roof top 2
F11. BIO-GENERATION BIOMASS PLANT
Electrical Power: 0.93 MW Heating Power (Steam): 5.4 MW Cooling Load: 675 kW Steam Production Capacity: 9.5 tons/ hour CO2 Reduction: 13,280 tons/annum
Flow chart of energy generation in Biomass plant
Heat Energy – Derived from the steam generated in the boiler system; Used for the regeneration of the liquid desiccant where the latter is utilized to create a dry atmosphere. Heat energy is also used in the operation of absorption chillers.
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F12. WATER SYSTEM S.No 1.
Existing 100 % potable water supply
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Proposed Rainwater harvesting pits Catchment basins to catch run off water Grey water recycling
F13. GREEN SYSTEM
Comparative analysis of REE tower before & after landscaped roof garden
ECOLOGICAL BENEFITS • Protection from direct solar heat • Storm water management & water retention • Improvement of microclimate • Dust & toxic particle binder • Utilize fly ash from biomass plant • Thickness of soil: 500mm (shrubs) & 1500 mm for trees • NATIVE ROOF PLANTS • Garcinia humbroniana • Ghetum ghemun • Money plant • Vitiver grass FLOWERING PLANTS • Lasia spinose • Lumnitzera Littorea • • • • •
SHADING TREES African Mahogany Rain tree Camphor Cluster palm
F14. SEWAGE TREAMENT PLANT
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Waste reduction & management Energy production Fertilizer production
F15. Elevators Energy Regeneration System (EERS) • Software- and microprocessor-based controls instead of electromechanical relays • In-cab sensors and software that automatically enter an idle or sleep mode, turning off lights, ventilation, music, and video screens when unoccupied • Destination dispatch control software that batches elevator stop requests, making fewer stops and minimizing wait time, reducing the number of elevators required • Personalized elevator calls used with destination dispatch controls that eliminate the need for in-cab controls. • Recover 20% of the energy consumed • Microprocessor based controls
Mid- and high-rise buildings typically have geared or gearless traction elevators capable of high or
variable speed operation. One energy-saving change manufacturers have recently begun to offer is
double-deck elevators. They are two cabs tall, one stopping at even-numbered floors and one serving
odd. They can reduce a building’s overall energy usage by reducing the number of stops and even the total number of elevators required when used with destination dispatch controls
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G. VISION
Sankey Diagram showing Energy Consumption & Energy Produced
G1. ENVIRONMENTAL IMPACT • • •
Decrease in energy consumption of the building by 40% Reduction in carbon emissions by 36%
Reduction in consumption of electricity from grid by 75%
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Reduction in thermal radiation received by the building by 62%
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Reduce dependency of building on air conditioning.
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Increase in Indoor air quality & thermal comfort because of natural ventilation.
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Decrease in potable water requirement by 30
% (use of rain water harvesting pits)
Future vision of the building in the new location
G2. RECOMMENDATIONS • The furniture, seating, carpet, glass, composite wood, aluminum, false ceiling - recyclable material. • Use of Phase Change Materials- Plaster • All paints, adhesives, furniture, carpets and housekeeping chemicals- eco-friendly and free of harmful components. • Waste bins for different categories of waste have been provided.
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