ZEB Plus @ BCA Braddell Campus

From Zero Energy to Positive Energy Building

Green Buildings Innovation Cluster (GBIC) Programme
Best-in-Class Super Low Energy Building Series | Positive Energy Office Building (Existing Building)Contents
Introduction 								

5Designs & Innovations					7

•Adaptable

9

•

Smart

12

•

Healthy14•

Biophilic

16•

Renewables							17

•Conclusions & Highlights					

18Reflections

		

20

Taking The Next Steps

23

Acknowledgements

25

Disclaimer | Editorial Team26

ZEB PLUS @BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

2

Foreword
To support Singapore’s commitment on climate change, BCA partnered the Singapore
Green Building Council and other Built Environment (BE) stakeholders to roll out theSingapore Green Building Masterplan (SGBMP) in 2021. The SGBMP aims to deliver three
key outcomes of ‘80-80-80 in 2030’.
When the BCA’s Zero Energy Building (ZEB) at our Braddell Campus was unveiled in 2009,it was one of the first retrofitted net zero energy buildings in Asia, producing sufficientenergy on its own to offset its consumption. Since then, we have continued to work withvarious partners to invest in research and innovation (R&I) to push the boundaries ofenergy consumption. Through collaboration with our local and international innovation
community, ZEB is now ‘ZEB Plus’, a positive energy building producing at least 20%
surplus energy than it consumes.
BCA, with the National Research Foundation’s support, seeks to promote research andshowcase advanced technological solutions to achieve net-zero and beyond, and also
to connect BE technology partners with leading sustainable developers to pilot green
building solutions. ZEB Plus will continue to offer itself as a living lab for both our local andinternational innovation community to develop and test innovative solutions.
Through ZEB Plus, we hope to inspire BE stakeholders to work towards decarbonisationand take charge of their sustainability journey.

Mr. Kelvin WongCEO
Building and Construction Authority

ZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

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Foreword
Buildings contribute over 20% of Singapore’s carbon emissions. Greening thesebuildings is hence crucial to our commitment to achieve net zero emissions by 2050.
With global demand for green buildings on the rise, it is also a market opportunity forour companies in the built environment sector.
BCA and the National Research Foundation (NRF) introduced the Green Buildings
Innovation Cluster (GBIC) programme in 2014, as an integrated research, development
and demonstration programme to accelerate the development and deploymentof promising energy efficient technologies in buildings. Funding for the GBIC wasenhanced by $45 million under the Research Innovation and Enterprise 2025 plan, toaccelerate the commercialisation of such technologies through industry partnerships
and help grow the local ecosystem of firms with green building expertise.
While we have greened close to 55% of our buildings (by Gross Floor Area), a greater
challenge is to green and enhance the energy efficiency of existing, older buildingsthat formed the majority of the built environment. To encourage this transformation,
the existing Zero Energy Building (ZEB) was recently retrofitted and BCA partneredwith researchers from SinBerBEST, a research programme under the NRF Campus for
Research Excellence And Technological Enterprise to deliver the ZEB Plus.
Today we are pleased to announce that the ZEB Plus is on track to achieve a
20% improvement in energy efficiency and I would like to take this opportunity
to congratulate BCA for taking a step closer to the Singapore Green Building
Masterplan’s targets and wish them success towards a greener and more sustainablebuilt environment.

Mr. Beh Kian TeikCEONational Research Foundation

ZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

4INTRODUCTION
Background
Singapore has committed to the goal of achieving net-zero emissions by 2050, as well as aiming to reduce emissions to
60 million tonnes of carbon dioxide equivalent (MtCO2e) by 2030 after peaking emissions earlier. Buildings account for
more than 20% of the country’s total carbon emissions, which plays a major role in reducing carbon footprint to mitigate
climate change.
As the world looks towards an increasingly uncertain future disrupted by climate change, the need for sustainably
designed buildings has never been greater. Although the pace of developing building technologies has accelerated,
there is still a considerable need to retrofit sustainable solutions to existing buildings.
In 2009, Singapore launched the first Zero Energy Building (ZEB) at the BCA Braddell Campus. Retrofitted from an existingbuilding, it is also the first of its kind in Southeast Asia.
The ZEB at BCA offers a glimpse into the buildings of tomorrow, today. Through the use of energy saving technologies,
ZEB only consumes half the energy of a typical office of the same size. With the inclusion of on-site renewables produced
by solar panels, ZEB has achieved net-zero energy for more than 10 years.

From a Zero to Positive Energy Building1
In the past decade, technological advances and intensified national efforts have been shaping the landscape ofSingapore’s built environment. Greater opportunities to develop, deploy and mainstream technological innovations topush the boundaries of energy efficiency in buildings have arisen.
These developments have been a powerful catalyst for realising BCA’s aspirations of achieving net-zero and Super Low
Energy buildings that are at least 60% more energy efficient compared to 2005 levels.
ZEB has inspired many forward-looking building owners and developers in Singapore and the region. An increasing
number of Zero Energy or Super Low Energy Buildings have emerged in the last decade, as part of the concerted efforts
to reduce carbon emissions and combat climate change.
Moving forward, in 2019, BCA partnered with the Singapore-Berkeley Building Efficiency and Sustainability in the Tropics(SinBerBEST), a research entity under the National Research Foundation CREATE Programme, to embark on a researchcollaboration to transform BCA’s Zero Energy Building (ZEB) into a positive energy building, ZEB Plus, which serves as aunique living laboratory for smart building technologies. This transformation was completed in 2022, heralding the arrivalof ZEB Plus. With the integration of green technologies into working spaces, the ZEB Plus, an “Office of the Future”,
provides insight into what tomorrow’s office buildings could look like.
The ZEB was recognised as one of the most energy efficient buildings in Singapore with energy efficiency 50% better
than a code-compliant building. Together with the upgrading of the existing solar PV system, the building has pushed
its boundaries further and has achieved an overall energy surplus of more than 20%. ZEB Plus has also achieved about
77% improvement in energy efficiency as compare to 2005 baseline.
This was made possible by leveraging the latest green building technologies and integrating them into ZEB Plus’s various
building systems, such as air-conditioning, lighting, building management system and solar panels. More than 1,000
sensors feed data back to a centralised AI engine, which enables the building to continuously adjust itself to deliver themost optimum energy performance.
1

A positive energy building refers to a building that produces at least 15% energy surplus with energy supplied by onsite renewable energy sources.

“

ZEB has inspired many forward-looking building owners and developers in
Singapore and the region. An increasing number of Zero Energy or Super Low
Energy Buildings have emerged in the last decade, as part of the concerted
efforts to reduce carbon emissions and combat climate change.

ZEB PLUS @BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

5ZEB Plus @ BCA Braddell Campus

High Efficiency
Solar PV System

Second Level Layout

Radiant Cooling System

First Level Layout

Power-over-Ethernet
lighting

Occupancy
Positioning System

HybridCooling

Desktop
Environmental
SensorPlug LoadMonitoring
and Control

ZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

User-Personalized
Space Setting Apps

6

ZEB Plus @ BCA Braddell Campus

Design & Innovation

ZEB PLUS @BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

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Overview
ZEB Plus is a co-innovation project with the research community that translates research and innovation into practicalapplications. The technologies demonstrated at ZEB Plus provide practical use cases where building owners and industry
stakeholders can refer to and apply in their own Super Low Energy (SLE) journeys.
As a living laboratory that test-beds new and innovative green building technologies, the ZEB Plus showcases state-ofthe-art solutions that seek to push the boundary of SLE buildings and improve energy efficiency for best-in-class buildings.

A

B

C

D

E

Hybrid coolingsystemRadiant
cooling system

User personalized
space settings
application

Plug loads
management

Power-over-Ethernet(PoE) lighting integrated
with daylighting andglare control

Key Features
HEALTHY
Features that are user andenvironmentally friendly

SMART

BIOPHILIC

Features that provide
performance monitoring
and controls

Features that are user andenvironmentally friendly

ADAPTABLE
Flexibility to adjust
environmental conditions
according to occupants’
preference

As an“Office of the Future”,
ZEB Plus was designed
to incorporate
five main features

ZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

RENEWABLES
Incorporates
renewable energy source
to offset energy use

8ADAPTABLE
Hybrid Cooling System - Elevated Air Movement andIncreased Temperature Setpoint Air-Conditioning System
Many commercial buildings in tropical climates are overcooled, causing energy waste and occupant dissatisfaction. As
the population in tropical countries grows, it becomes increasingly crucial to reduce the reliance on air conditioning (AC).
The Hybrid Cooling System allows indoor air temperature to be increased and provides greater air movement with ceilingfans as needed. Through an app, occupants have direct control of their environment which can enhance their thermalsatisfaction. Each desk has a desktop sensor that measures and monitors indoor environmental conditions, such as
relative humidity and lighting level.
The Hybrid Cooling System can provide substantial energy savings. Energy analysis for tropical buildings has shown thatup to 45% in cooling energy savings can be achieved by increasing the cooling temperature setpoint from 24 °C to 27°C.
Through test bedding at ZEB Plus , changing the setpoint temperature from 24°C to 27°C with the introduction of ceilingfans has increased occupant satisfaction from 60% to 90%. Also, the best cognitive performance (as indicated by task
speed) was obtained at 26°C. In this smart building, 27 ceiling fans has been installed while the air temperature is set at
a minimum of 26°C. Additionally, each work desk has a desk fan for personalised comfort.
Technology on Workstation Desk
2
1

3
6
4

7

5
Closed-loop control over PoE lighting and roller
blinds utilizing desktop sensor maximizing
daylight while providing individual task lighting.

1

Elevated Air Movement2

High-Performance PoE (Power Over Ethernet)
Based Dimmable Ceiling Luminaire

3

Personal Desk Fan

4

Desktop Sensor

5

User Personalized Space
Settings Application

6

Dimmable Desk Lamp

7

Monitored Plug Lead (inset)

Data is harvested,
processed anddisplayed through UPSS

Most importantly, occupant feedback provided to theUser-Personalized Space Settings (UPSS) application
informs the system whether an increase or decrease in
air movement or temperature is preferred.

ZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

9A D A P TA B L E

Hybrid cooling allows indoor air temperature to be increased and provides greater air movement with ceiling fans asneeded. This provides up to 45% in cooling energy savings and enhances thermal comfort.

Elevated Air Temperature and Movement

ZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY10A D A P TA B L E

Radiant Cooling System

Radiant cooling refers to the use of cooled surfaces toremove sensible heat (heat from people, lights, computersetc.) emitted through radiation. In a radiant cooling system,
radiant panels cooled by chilled water remove sensible heat
while humidity is removed with a Dedicated Outdoor Air
System (DOAS) which provides cool and dry air to the space.
In a typical air-conditioning system, both sensible heatand humidity are removed by providing cool and dry air tothe space. The radiant cooling system uses water as a heattransfer medium to remove heat, which is more energy
efficient than air.

The radiant cooling system uses
water as a heat transfer medium
to remove heat, which is moreenergy efficient than air.

Thermal Comfort of Radiant Cooling

Radiation
The emission or transmission of energy in theform of waves or particles through space.
Convection
The process by which heat is transferred by
movement of a heated fluid such as air orwater.

Heat is lost from the human body
mainly through radiation

Conduction
The process by which heat is directlytransmitted through the material of a
substance when there is a difference oftemperature without movement of thematerial.
Evaporation
The process of turning fromliquid into vapour.
Radiation: 40 - 50%

The temperature distribution in the room
is more uniform because there arefewer sources of air flow

Convection: 20 - 25%
Evaporation: 20 -35%
Conduction: 3 - 5%

Copyright: K Thompson College of Louisiana at 250C

ZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

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A D A P TA B L E
The radiant panels which remove sensible heat (heat from people, lights, computers etc.) are operated in combination
with the Dedicated Outdoor Air System (DOAS) which removes humidity by supplying cool and dry fresh air.

Radiant Cooling System Schematic

Sensible Heat Processing System
Chilled Water Return

Fresh Air Fan

Chilled Water Supply

Cold & Dry air:
20 °C, 45% RH
Outdoor Air

Radiant Ceiling Panels

Warm & humid air:
31°C, 80% RH

Radiant Panel Surface Temperature: 16 - 21 °C

26 °C, 50% RH

Dedicated
LatentHeat
Outdoor
Processing
Air
SystemSystem(DOAS

Note : RH – Relative Humidity

The radiant panel uses a higher chilled water temperature of 15 - 180C for
cooling rather than the typical 6 - 80C for a conventional air distribution
system. At this higher water temperature, the chiller plant efficiency cansignificantly be improved, hence reducing energy use for cooling.
This particular system results in 30 to 35% energy savings for coolingas compared to a conventional air distribution system. It also enhances
occupant thermal comfort by ensuring more uniform temperature
distribution within the space, a low noise level and absence of draft.

ZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

30 to 35%
expected energy savings forcooling as compared to aconventional air distribution system

12SMART
Smart Office Desk Plug Load Monitoring & Control
and User-Personalised Space Setting (UPSS) Application

To reduce plug load or energy consumption by plugged devices, smart plugs
to control and monitor energy consumption were introduced at the ZEB Plus
office. In this building, each desk is fitted with six power sockets equippedwith energy metering capabilities.
Occupants can keep track of their own energy utilisation behaviour andschedule when to turn on or off their devices through the UPSS application.
Facility managers can also analyse energy consumption patterns acrossoccupants and encourage behaviours to reduce energy consumption throughthe application without affecting their day to day work and productivity.

Plug load

Presently, many buildings do not take into consideration the desired
environmental conditions by occupants. Despite low levels of satisfaction
from occupants, they often receive the same levels of thermal conditions,
air quality and lighting. In this building, the UPSS software is able to solicit
occupant’s preferences in terms of air temperature, air movement andlighting. The control algorithms will then tweak the system to adapt to theirneeds, thus leading to better satisfaction while simultaneously minimizing
energy use.
UPSS software

ZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

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SMART

PoE Lighting and Active Use of Daylight
The central lighting system utilises ultra-low power LEDs powered by Ethernet(PoE) instead of normal power cables, which is expected to save up to 30% oflighting energy. A total of 53 PoE lights were installed in a closed-loop design
configuration to ensure light is delivered into the space such that a minimum
level of light is uniformly distributed on desks.
The lighting that occupants receive can originate from either artificial or
natural sources of illumination. When there is sufficient daylight in the space,
the central lighting system reduces reliance on electrically powered lights andthus saves more energy. Should the incoming daylight excessively exceed thetarget light level, a feedback signal will be sent to the roller blinds to reduce
the light received on the surface. These controls are also programmed so thatwhen the light is below the target level, the roller blinds will be retracted.
Because of the high degree of control over many important lighting
parameters, the SinBerBEST team has been able to develop and test thelighting controls under a wide range of conditions in a relatively short periodof time. Additionally, should occupants prefer a more personalized lighting
level on their desks, they can control lighting level directly through the User
Personalised Space Settings (UPSS) application.

“

The central
lighting systemutilizes ultra-low
power LEDs by
Ethernet, which is
expected to save

up to 30%of lighting energy.

Central Lighting System utilising PoE Lighting and Daylighting to Optimise Lighting Level

Power Over Ethernet Light

Adjust Lighting

Light
Controller

Minimum
Illuminance

Measured Light
Light Sensor

ZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

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HEALTHY
Demand Controlled Ventilation (DCV)
Essentially, the smart ventilation system automatically adjusts the air
flow of outdoor air into the office space according to the occupancy
level , saving up to 20% of AC energy. Using carbon dioxide sensors in
the indoor environment, the control algorithm modulates the volume
of outdoor air flow into the entire office via the air-conditioning
mechanical ventilation equipment.

The smart ventilation system
automatically adjust the spaceventilation requirements
according to the occupancy
level of the office, saving up to

The new innovation in this design involves the occupancy positioning
system (see below) within the zones that detect the actual numberof occupants to provide accurate outdoor airflow in compliance with
ASHRAE Standard 62.1 and Singapore Standard SS554.

20% of AC energy

This ensures that the carbon dioxide levels are kept at an acceptablelevel within the enclosed space, thus enhancing the indoor
environmental quality and the occupants’ health.

and enhancing the indoor
environmental quality andoccupants’ health.

DCV System at Full Occupancy
AC Mechanical Ventilation System
Fully Opened Outside Air Damper
Exhaust Air DamperMoreoutsideair needed

DCV System at Partial Occupancy
AC Mechanical Ventilation System
Partially Opened Outside Air Damper

CO2 sensor

Exhaust air damper
ControlPanelLessoutsideair needed

100 CFM* Exhaust
Air Required

Source: Yorkland Controls

CO2 sensor

Control
Panel*Cubic Feet
Per MinuteSource: Yorkland Controls

ZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

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BIOPHILIC
Direct and Indirect Features
To encourage a collaborative and healthier workplace, the office wasdesigned to incorporate biophilic features. Biophilic designs andfeatures are important because of their positive effects on mental andphysical health. In 2020, the World Health Organisation (WHO) statedthat more than 264 million people of all ages around the world sufferfrom depression. As such, the ZEB Plus office aims to have a positive
impact on well-being.
One biophilic feature is the presence of indoor plants in the office, whichwere carefully selected during the design stage. Dedicated LED lights
were installed to promote their growth.
In terms of interior space features, the ceiling panels were designed
to look like a “honeycomb” to emulate nature. They also function as“acoustic panels” to reduce sound level within the space.

Biophilic designs and features
are important because of theirpositive effects on mental
and physical health.

Direct features: “Super Tree” and indoor plants

Indirect features: “Honeycomb” design

ZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

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RENEWABLES
High Efficiency Solar PV System
While cutting down on energy consumption is one
critical requirement for achieving zero energy, it is
not enough. Inevitably, energy would be required to
power equipment and systems throughout a building;hence, the building must be able to generate at leastsufficient energy to meet such needs.
Prior to the retrofit, an energy surplus of between
7 and 9 percent had been achieved through the
adoption of solar PV systems over a 10-year period.
As part of the retrofit to achieve its positive energy
building target, the existing solar PV system for themain roof was replaced with more efficient panels(22.3% @ 395 Wp/panel) as compared to the original
one of about 13%.
Based on actual data and occupancy of the space,
ZEB Plus has achieved an average 42% energy
surplus for the last 2 years. With full occupancy, it isexpected that the surplus will be about 20%, which
would still make it a positive energy building.

ZEB Plus’ Consumption versus
Generation Performance (Actual)
MWh/yr

42%

300
250

26%

surplus224

surplus

224

200
150

165.9
129.04100
50
030 to 40% Occupancy (actual)

Generation

Adjusted Occupancy at 80%

Consumption

SunPower MAXEON 3
Total Installed Capacity: 195.13 kWp
Panel Power: 395 Wp
Panel Efficiency: 22.3%
Total No. of Modules: 494 nos.

ZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

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Conclusion
Technologies demonstrated at ZEB Plus provides best practices and strategies for practical Super Low Energy (SLE) uses
cases where industry (building owners/developers) can refer to and apply in their own SLE’s journeys.
The project also highlighted the public sector’s commitment to sustainable low-carbon buildings in support of theSingapore Green Building Masterplan (SGBMP). By leveraging research and innovation, through close collaboration withindustry players and research institutions, the project hopes to inspire the industry to replicate these to mainstream SLE
buildings towards a low-carbon built environment.

Highlights
ZEB Plus’s Overall Performance Indicators

Achieved 77% energy
efficiency improvement
as compare to typical
office in 2005)

Generated >20%
net surplus energy
from the on-sitehigh-efficiency
solar PV panels“

Cumulative Energy
Consumption

77%
Cumulative Energy
Production
Typicaloffice>20%
EnergysurplusZEB Plus

Achieved >90%
occupants’ satisfaction
rate on occupantcomfort leading tohigher productivity
gains

Energygeneration
through PV

ZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

Leveraging researchand innovation, thepublic sector is leading
the way for Singapore
to mainstream SLE
buildings towards
a low carbon-built
environment.

18

Lower Energy Use,
Higher Comfort Acceptability
and Better Satisfaction Results

Increase in set-point temperatureof ceiling fans from 24 °C to 26.5 °C
with fans added

Based on a study which surveyed a total of 35 occupants on thermal comfort
and satisfaction over a 11-week period, setting a higher air conditioning
temperature with elevated air-movement produced by ceiling fans does notcompromise thermal satisfaction. In fact, the results show an improvement in
comfort acceptability from 55% to 77% by raising the set-point temperaturefrom 24 °C to 26.5 °C.

Improvement in occupants’
comfort acceptability

to 77%

By increasing the temperature set point and supplementing this with elevatedair-movement, a cooling energy savings of 32% was also achieved.

from 55%

Cooling Energy Saving Results
Chiller
AHU & fresh air fansFan
(26.50C)

Pumps
Cooling towers

15.7

6.5

Ceiling fan
Desk fan

1.3

32%

reduction
No Fan(240C)

22.4

0

9.9

10

20

3.3

30

40

Energy use intensity (kWh/m .yr)
2

Comfort Acceptability and Satisfaction Results
Right now, would you prefer to be...
CoolerSlightly cooler
26.50C (fan)n = 39712%240C (no fan)n = 452

8%

No change
Slightly warmer

Right now, how satisfied are you?

Warmer77%

55%

Dissatisfied

8%

29%

Improved acceptability at higher
set-point temperature with ceiling fans

ZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

Neither satisfied
nor dissatisfied

Satisfied

3%

34%

63%

7%

29%

64%

Better thermal satisfaction
was established19

ZEB Plus @ BCA Braddell Campus

Reflections

ZEB PLUS @BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

20SinBerBEST is honoured to have played a major role in transforming the first floor of BCA ZEB Plus to aliving laboratory.
Our paradigm of looking at buildings as a factory or assembly line which manufactures the indoor conditions
for occupants meant that our design for the living lab took a holistic approach.
The SinBerBeST technologies deployed at the living lab span the breadth of building systems: a lighting
control system for daylight harvesting and visual comfort, a hybrid cooling system in which air conditioning
works in tandem with ceiling fans, sensor network for IAQ monitoring, a granular Energy Metering System forplug load management, occupancy positioning system for demand-based ventilation, and User Personalised
Space Settings Application for real-time user feedback.
A Testbed Building Management System ties all the technologies together by taking the real-time feedback
from occupants and adjusting the SinBerBEST systems to meet their demands.

This project was a good opportunity to share
our state-of-the-art net zero energy solutions forbuildings in the Southeast Asia region. These
solutions include a radiant ceiling panel for sensible
cooling and decoupled latent cooling system.
The challenge was how to bring a proven HVAC
technology in Japan to a different climate region
such as Singapore’s hot and humid climate. A
simulation tool has been utilized to develop the
optimized layout of the radiant ceiling panel anddew point temperature monitoring. We also installed
a water leakage sensor to prevent condensation.
Another challenge was to reduce the energy
consumption by implementing operative
temperature control with radiant cooling system.
Convective enhanced radiant ceiling panels havebeen also used to increase the cooling capacities inthis project.

ZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

We were able to work through various issues asa team because BCA (building owner) and SBB(collaborating researchers) are open minded andadaptable project partners. Working with theserespective stakeholders of the project team tointegrate the latest technologies into modernbuilding systems and bring their ideas into reality
was a challenging and enriching experience.
Being a member of this project offers wealth ofknowledge, such as the interfacing withtechnologies which are typically not a part ofa conventional building/construction project.
Furthermore, the fact that ZEB was an existingbuilding presented another challenge where
designers needed to work with an operatingbuilding.

21

ZEB Plus’ Design Approach and Solutions

Specifically for ZEB
Plus, the main challenge
faced was catering todifferent user needs andpreferences, especiallyon aspects such as
office layout and coolingprovision in the building.
While working towards
reducing energy use, we
also had to keep in mind
the thermal comfort for
occupants. Their opinions
were also sought for
matters pertaining topersonal spaces, suchas cubicle design.

To overcome thischallenge, an integrated
design approach
was adopted, where
all stakeholders(management, projectteam, occupants, andconsultant team) werebrought together andprovided suggestions
and feedback on theirideas for the new space.
Constant updates were
provided by the project
team to stakeholders
on the progress of the
project.

At ZEB Plus, it is ourbelief that buildings
are for people andtherefore, building
occupants in turnhave a part to play insustainability practices.
Building occupants
therefore are given
better control over theirworkspace through asmart mobile app. Theapp allows them to notjust review their dailyenergy usage but alsobenchmark their usage
against their colleagues.
Building occupants canalso use the app tocontrol the speed of theceiling fans, adjust thelighting intensity, andmanage the smart plugs
which power up theirelectrical devices.

ZEB PLUS @BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

22

ZEB Plus @ BCA Braddell Campus

Taking The
Next StepsZEB PLUS @BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

23

Looking beyond the present, ZEB Plus serves asa Living Lab for many innovative and emerging
green building solutions. Through collaborations
with research and industry partners, ZEB Plus
has been the hub for research activities thatpush energy efficiency further. This includes
testing LED lights powered by internet cables,
Indoor Air Quality sensor network, and radiantcooling systems with heat recovery to validate
the performance and interest industry partners
to adopt these technologies.
Through the proactive use of the latest green
building technologies, empowering building
occupants and being a testbed for emerging
green technologies, this three-pronged approachallowed ZEB Plus to achieve an energy surplus
of more than 20%, which is then returned to thegrid as clean energy stock.

ZEB Plus’ Three-Pronged Approach

Proactive use of thelatest green building
technologies

Empowering building
occupants

The empowerment of occupants encourages
them to be more aware of their energy usage andmotivates them to take positive steps to reduce
their energy consumption, hence contributing tolower energy usage at ZEB Plus.
ZEB Plus will continue to serve as a live
demonstration for future high-performing
buildings and environmental sustainability in
Singapore.

Being a testbed
for emerging green
technologies

ZEB PLUS @BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

24

Acknowledgments
Research Partner:

Industrial/Research Partner:

M&E Consultant:Architectural Consultant:

Quantity Surveyor :Main Contractor:

PE\RFOR<M INDUSTRIES PT£ LTD

Solar PV System Contractor:

SolarGyZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

Pte Ltd

25

Disclaimer
This publication is electronically published by the Building and Construction Authority.
Copyright @ Building and Construction Authority, Singapore, 2023 - 2024.
All rights reserved. This document or any part thereof may not be reproduced for any reason whatsoever in any formor means whatsoever and howsoever without the prior written consent and approval of the Building and Construction
Authority.
Whilst every effort has been made to ensure the accuracy of the information contained in this publication, the Building
and Construction Authority, its employees or agents shall not be responsible for any mistake or inaccuracy that may becontained herein and all such liability and responsibility are expressly disclaimed by these said parties.

Editorial teamAng Kian Seng | Group Director, Environmental Sustainability Group
Wong Ngian Chung | Principal Manager, Green Building Policy and Technology Department
Majid Sapar | Senior Manager, Green Building Policy and Technology Department
Cheng Yui Seeng | Executive Communications Manager, Corporate Communications Department

Design by: Kudos Graphics | https://kudosgraphics.com | Photos by: Glen Goh

ZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

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ZEB PLUS @ BCA BRADDELL CAMPUS | FIRST EXISTING OFFICE BUILDING ACHIEVING POSITIVE ENERGY

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