Lighting    
 
Replace T12 or T10 fluorescent tubes with T8 or T5 energy efficient fluorescent tubes, which are 10% to 30% more energy efficient.
1
 
Replace incandescent light bulbs with compact fluorescent lamps, which are 70% to 80% more energy efficient.
1
 
Replace electromagnetic ballasts with electronic ballasts, which are 20% to 30% more energy efficient.
3
 
Install lighting zone control wherever applicable to switch off unnecessary lighting in unoccupied areas.
3
 
Install occupancy sensors to automatically control lighting in areas infrequently used, e.g. conference rooms.
3
 
Install parabolic-type lighting reflectors to reflect sufficient light and use fewer fluorescent tubes.
3
 
Install appropriate dimmers to adjust lighting.
2
 
Remove excess lighting in areas that are unnecessarily bright and maintain only those lights needed for safety, security or other specific purposes in the areas frequently unoccupied.
2
 
Make use of daylight whenever possible.
1
 
Clean lighting luminaries and avoid switching on unnecessary lights.
2

Heating, Ventilating & Air-Conditioning System (HVAC)
 
 
 
Replace aging HVAC equipment with new energy-efficient equipment.
3
 
Install variable-speed drives wherever applicable to control chilled water flow and fan speed based on actual demand.
3
 
Use heat-recovery chillers or heat pumps to recover waste heat that can be used for heating up the hot water supply while providing cooling at the same time.
3
 
Install occupancy sensors to automatically switch on and off the air-conditioning in those areas infrequently used, e.g. in conference rooms.
3
 
Increase the chiller evaporator temperature and decrease the chiller condensing temperature according to the chiller manufacturer's recommendations so as to achieve higher chiller cooling efficiency.
3
 
During cool seasons, raise the chilled water supply temperature according to the cooling demand. This improves the efficiency of the chillers running at part load.
3
 
When outside conditions are suitable and the outdoor air is cool and dry enough, intake of outdoor air should be increased.
3
 
Regularly clean condenser tubes, cooling coils and air filters in order to maintain cooling efficiency.
3
Office Equipment
 
 
 
Purchase energy-saving models of office machines, e.g. photocopiers and laser printers bearing the energy labels.
2
 
Adopt paper-reducing strategies such as double-sided printing, reusing paper and using e-mail instead of sending memos and faxing documents.
1
 
Always switch off office equipment such as personal computers, printers and photocopiers when they are no longer needed, e.g. during nighttime and at weekends.
1
 
Discourage the use of personal electrical appliances such as electric fans.
1
Building Envelope (external walls, roofs and floors in direct contact with ground)
 
 
 
Install self-closing doors on openings to non-air-conditioned spaces to reduce excessive infiltration and exfiltration.
3
 
Install caulking or replace worn out caulking around windows, doors or other areas of infiltration / exfiltration.
1
 
Realign or re-hang windows or doors that do not close properly.
1
 
Replace broken or cracked windows.
1
 
Install outdoor shading devices, add reflective films to windows, and close interior shading devices, e.g. curtains or venetian blinds (preferably light coloured), to reduce solar heat gain in summer.
2
Other Machinery and Equipment
 
 
 
Install energy-efficient motors and do not use oversized motors because motors are inefficient when running at part load.
1
 
Operate machines at maximum efficiency. Always run fewer machines at full load rather than more machines at part load.
1
 
Install variable-speed drives to control motor speed to meet demand if loads fluctuate in application.
3
 
Lubricate motors and drive bearings frequently to avoid overheating and power loss.
2
 
Adhere to proper maintenance schedules recommended by manufacturers.
2
 
Regularly clean the heating coils in the electric boilers.
2
 
Use heat pumps to heat up water wherever applicable, e.g. for swimming pools and hotels.

3
 
Consider localised hot water supply. This eliminates heat losses in long pipe runs and the need to operate large units for small, intermittent heating demands.
3
 
Reduce the number of lifts or escalators in service after normal working hours and on holidays.
1