Clean Luminaires

It is important that the reflective surfaces of the luminaires are kept clean, or the light output will be reduced. Cleaning the luminaires will not save energy in itself, but with cleaner luminaires, you can maintain a better level of lighting for the same energy use. Cleaning luminaires may reveal over-lighting which will permit other lighting design ECMs to be considered.

Replace lamps with higher efficiency units

Standard monophosphor 26mm fluorescent tubes are 10% more efficient than their 38mm predecessors. Compact fluorescent lamps are around four times more efficient than equivalent incandescent lamps. In both cases, substantial energy can be saved by a direct replacement.

De-lamping

Where light levels exceed Australian Standards or are poorly matched to user needs, it is often possible to save energy by removing unnecessary lamps and labelling de-lamped holders accordingly. This should only be done after luminaire cleaning. . See also Selective Replacement of Tubes, below.

Selectively replace tubes

Selective replacement of fluorescent tubes involves the replacement of lower light output monophosphor fluorescent tubes with higher light output triphosphor fluorescent tubes. The energy savings from this measure arise through the "selective" component, as fewer tubes are required to meet the same overall lighting levels.

• Improved unit efficiency. New triphosphor tubes are much more efficient than standard monophosphor tubes. The efficiency improvement is twofold ¡V the initial light out put is 10% higher, but the maintained light output is some 50% higher. As it is the maintained light output that has to be used in design, this translates into a major efficiency improvement.
• Improve light levels. The use of triphosphor tubes can also provide improved light levels for the same amount of energy. Where previous light levels do not meet standards, this can be an effective method of improving service without increasing running costs.
• Reduce over-lighting. As part of the re-examination of lighting levels that is necessary in selective re-tubing, overlit areas can be extensively de-tubed.
• Matching to user needs. As part of the re-examination of lighting levels that is necessary in selective re-tubing, the current uses of areas can be assessed and lighting patterns adjusted to better provide for occupant needs. This measure can save energy where some areas of a space do not need such high light levels as the work-stations. An example would be an office area that contains areas for storing files.

Replace Diffusers

The replacement of diffusers can improve efficiency if accompanied by de-tubing.

• Improved light output ratio. Egg-crate and opal diffusers are less efficient than prismatic plastic sheet diffusers. Metal diffusers are also relatively efficient, but they can be expensive. Standard prismatic diffusers are remarkably efficient and cheap. Egg-crate diffusers are designed for exceptionally low glare requirements and are often misused in locations where prismatic diffusers are perfectly acceptable.
• Improved light levels. Where inefficient diffusers have been used in an area that has substandard lighting, replacement of diffusers can lead to improved lighting at no additional energy cost.
• Matching to user needs. Low glare diffusers are often used in situations where there is no real need for such low glare characteristics. In this instance, changing to a standard diffuser can allow de-tubing to occur and energy savings to be made.

Reduce number of luminaires/Relocate luminaires

Reducing the number of light luminaires can reduce over lighting problems, improving occupant comfort and energy efficiency. Relocating luminaires relative to occupant work areas can reduce the number of luminaires required, reduce glare problems, and improve light levels.

Replace Ballasts

The replacement of ballasts in fluorescent luminaires can achieve some energy savings.

• PCB removal.PCB capacitors are common in fluorescent luminaires dating from the 1970s, but they contain materials that can cause cancer. Often the upgrade of ballasts can be undertaken if there is a program in place to remove PCBs for safety and health reasons.
• Unit Efficiency.Low loss and electronic ballasts can reduce power consumption by 10 and 20% respectively. In the absence of other reasons to be refurbishing the luminaire, ballast replacement is rarely cost effective by itself.

Refurbish Luminaires

In some instances, it is more cost effective to refurbish old luminaires than replace them. This is particularly the case if the luminaires are designed to fit into a non-metric ceiling grid.

• Install reflector.Specular (mirror) reflectors can be installed in luminaires to improve light output. These are particularly effective in luminaires where the interior surfaces are degraded, or where the original luminaire shape was inefficient.
• Replace control gear.Where the original control gear is incompatible with 26mm tubes or otherwise unsuitable for retention in refurbished luminaires, replacement of control gear can be an energy saving opportunity
• Reduce number of tubes.Particularly in 3 or four tube luminaires, the refurbishing of the luminaire can allow a reduction in the number of tubes.

Replace Luminaires

Replacement of luminaires can be more cost effective than refurbishing them, depending on the type of luminaire being replaced.

• Improved unit efficiency.There are a number of luminaires available on the market with high total light output ratios. These can be used to replace less efficient luminaires, with an overall reduction in the number of tubes producing good energy savings.
• Improved light levels.Where light levels do not meet Australian Standards, the use of more efficient luminaires can allow light levels to be improved with no increase in energy cost.
• Matching to user needs.The replacement of luminaires is a good opportunity to review the occupants' needs for lighting and improve the light distribution to mach these needs.