Energy Saving Technology for Office
Building
Electrical System
• Enhancement in system reliability
by feeding from 3 different primary
11kV substations, strengthening
the power supply as well as
strengthening the reliability of the
telecommunication facilities, etc.
• Power Monitoring System (PMS)
monitors the power supply quality
and the efficient use of electricity of
each electrical device/equipment/
facility
• Provision of emergency generators
to support back-up power
Lighting System
• Maximise the use of daylight
• Wide use of energy efficiency lights
like T5 tubes and LED lights
• Wide use of electronic ballasts
• Select lighting with effective
reflectors
• Building Management System (BMS)
is designed to control lighting in
common areas by means of time
schedules for appropriate lighting
zones
• To maximise energy efficiency, office
areas are located at the perimeter
whilst amenities areas and lift
lobbies are located at the inner core
of the building. Office room depth is
also restricted to maximise effective
daylight access
• Solar powered lawn lamps are used
at night
• Use of light tubes and light shelves
to capture daylight
• Use of task light with reduced
general illumination
Air-conditioning System
• Thermal Comfort Analysis is
conducted to compare different
design scenarios on solar heat gain
• Use of Variable Air Volume (VAV)
system for control of demand to
arrive at energy savings
• Energy efficiency and cleaning
devices are applied in the AC system:
ͳͳ Automatic condenser tube
cleaning system to maintain a high
heat transfer efficiency
ͳͳ Application of condenser water
filtration system with centrifugal
separator to prevent debris
accumulation and reduce fouling in
the cooling tower water circulation
and enhance the chiller COP and
save energy
ͳͳ Variable Speed Drives (VSD) for
secondary chilled water pumps,
cooling towers and
respectively
ͳͳ Variable primary flow configuration
for the chilled water system
ͳͳ CO
2
sensors are used to signal the
VSD control of the
to adjust the
airflow for fresh air ventilation
in the building’s common areas
in response to occupancy, thus
arriving at energy savings
ͳͳ Heat pumps for space heating
ͳͳ Hydronic balancing in chilled water
system
• Proper commissioning on air and
water side systems
Lift and Escalator System
• Overcoming dynamic effect in lift
shaft due to strong wind resulting
from piston effect- research and
aerodynamic modifications to
minimise high wind loads
• Use of high-speed double-decker
lifts can cut down the number of
lift shafts needed while a specially-
designed co-ordinated lift destination
control system with crowd control
sensors can ensure smooth vertical
passenger movements even in rush
hours
• Specially-designed regenerative
drives for lifts that make use of
surplus power to drive other lifts in
the same system
• Adoption of VVVF motors in all lifts
and escalators
• Use of service-on-demand escalator
Figure 3.3.6 Electrical System
(Source: Kai Shing Management Services Limited)
Figure 3.3.8 Fluorescent Light
(Source: Kai Shing Management Services
Limited)
Figure 3.3.9 Air-conditioning System
(Source: Kai Shing Management Services Limited)
Figure 3.3.7 Solar Tube
(Source: Kai Shing
Management Services
Limited)
Figure 3.3.10 Under floor cooling
(Source: Construction Industry Council)
Figure 3.3.11 High Volume Low
Speed (HVLS) fan
(Source: Construction Industry Council)
High-Volume-Low-Speed Ceiling
(HVLS) Fan
A patented airfoil and winglet design
is able to move a large volume of
air at a slow speed. As a result,
discomfort due to high humidity is
minimised from the higher rate of
evaporation through increased airflow.
The acceptable temperature for
inhabitants is raised by 2
o
C with an air
flow of 0.5m/s, thus energy savings
can be achieved.
Desiccant Dehumidification
Instead of overcooling the supply
air to achieve dehumidification,
a desiccant wheel handles the
dehumidification process separately
from the cooling system. Desiccant
is dried by recovered heat from the
Combined Cooling Heating and Power
(CCHP) system.
DESIGN STAGE
3.3.3 Energy Saving Technology
DESIGN STAGE
3.3.3 Energy Saving Technology
Office
BUILDING
Office
BUILDING
Case study of Zero Carbon Building:
Chilled Beams and Under-Floor Displacement Cooling
A high temperature cooling system with chilled beams and under
floor displacement cooling is used. In convective cooling, cool air
is distributed from the floor with a higher supply temperature
and lower air speed. The system operates at higher chilled water
temperatures and avoids another reheating process. For radiant
cooling, chilled beams cool and absorb heat from inhabitants and
spaces, requiring less pump and fan energy to deliver cooling.
Figure 3.3.12 Zero Carbon Building
(Source: Construction Industry Council)
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