Energy Saving Options to Upgrade Fluorescent Tubes

T8 fluorescent tube lighting is used widely at many sites, particularly in car parks, utility rooms and fire stairs. While fluorescent tube lighting is generally quite efficient there are still several cost-effective options to upgrade T8 lighting and achieve energy savings.

Below we outline 7 of the best energy saving options to upgrade fluorescent tubes

1. De-lamping

De-lamping refers to removing one fluorescent tube from a twin fitting. It can be a low-cost energy saving measure in areas which are over lit and can support a reduction in light output. A typical application of de-lamping in apartment buildings is lighting over spaces in car parks. Light levels are often much higher than the recommended lux.

The big disadvantage of de-lamping is a 50% redcution in light output. Reflectors may be installed behind the remaining tube in order to minimise the reduction in light levels. Care must be taken ensure light levels meet building codes and Australian Standards.

De-lamping is not recommended in the case where a single ballast operates all tubes in a triple or twin fitting. When de-lamping it is recommended to also disconnect the ballast otherwise it may continue to draw 4W to 8W. For any job that requires modifying a luminaire an electrician is required to conduct the works.

2. Retrofit T5 tubes into existing fitting using T8 to T5 converters

T8 to T5 converters allow a high efficiency T5 lamp (including electronic ballast) to be installed into a standard T8 fitting. A 28W T5 lamp uses approximately 20% less energy than a 36W T8 lamp without reducing light output (this does not include additional savings that may be achieved through changing the ballast). Many T8 to T5 converters use 28W T5 tubes but only draw 22W to 26W due to optimised control circuitry. This means energy savings can be as high as 35%.

Many manufacturers claim T8 to T5 converters may be installed without an electrician. However, as the starter or ballast may have to be removed from the fitting before installation we recommend that an electrician conducts the works.

T8 to T5 converters typically cost ~$35 (including lamp). This means its generally cheaper to install T8 to T5 converters rather than replacing the entire fitting with a high efficiency T5 fitting. However, low installation cost should not be the only factor to be considerd. The use of T5 tubes and T8 and T5 converters can present an ongoing maintenance cost to the site. T8 fittings may have a lifespan of over 20 years however many T8 to T5 converters are only gauranteed for 5 years. Replacing T8 to T5 converters in the future can add an unwanted complexity for strata plans where replacing lights is often the responsibility of cleaners or tenants. Care must be taken to educate tenants, cleaners and maintenance workers of the requirements to use and replace T5 tubes, in particular to make sure the T8 to T5 converters are not removed. Once a T8 fitting has had its ballast removed to allow for the T8 to T5 converter it can no longer accept standard T8 tubes.

So in summary, yes T8 to T5 converters are a great low-cost option but if your fittings are old or in poor condition it may be a better long-term strategy to replace the entire fitting with a new high efficinecy fitting rather than installing new coverters into old fittings.

3. Retrofit LED tubes into existing fitting

LED tubes are available that offer light levels comparable to 36W fluorescent tubes. Replacing a 36W T8 fluorescent tube with a 19W LED tube can save 55% (including energy of ballast).

The wattage and cost of LED tubes to replace 36W T8s varies considerably between manufacturer. Through a quick google search of LED tubes we found 20 suppliers selling LED tubes that range from 15W to 24W at at cost of $25 to $90 (the Osram 24W tube being the most expensive at $90).

While LED tubes are designed to fit directly into existing fluorescent fittings they typically require removing and replacing the starter. Many manufacturers claim LED may be installed without an electrician. However, as the starter or ballast may have to be removed from the fitting before installation it is recommended that an electrician conduct the works.

LED tubes are a good energy saving option, they can cost more than T8 to T5 converters but LED tubes they have a significantly longer lamp life. LED tubes are particulary suited for motion sensor applications (e.g. garbage rooms) where frequent switching on and off would reduce the life of a fluorescent tube. As LED tubes are an emerging technology it is recommended to trial their use prior to widespread implementation, and we always recommend to err on the side of caution by buying the more expensive tubes from reputable brands.

Care must be taken to educate tenants, cleaners and maintenance workers of the requirements to use and replace LED tubes. Inserting a LED tube into a standard fitting without removing the starter may destroy the LED tube. A standard T8 tube may malfunction if inserted into a fitting that has been modified to accept either LED tubes or T8 to T5 converters.

4. Dimmable LED light fittings with inbuilt occupancy sensors

LED fittings are available with inbuilt occupancy sensors and dimming controls. During periods when an area is vacant the fittings automatically dim to provide low level security lighting while consuming relatively low power. When the occupancy sensor of a fitting is triggered the lamp increases to full brightness. Significant energy savings may be achieved in areas with low levels of occupancy.

The enlighten Chamaeleon LED fitting that has an unoccupied power consumption of 6W and an occupied power consumption of 28W. The fitting provides a light output similar to a twin 36W fluorescent fitting. The unit costs from $250 to $350 depending on the number of LEDs and whether it is an emergency fitting. While the unit cost is high the energy savings are even higher. In areas of low traffic such as fire stairs energy savings of over 90% can be achieved. Another advantage of the Chamaeleon LED fitting is that there is an emergency fitting option so it can used to replace all fluorescent fittings at a site. LED tubes and T8 to T5 converters are not recommended for use in emergency fittings. Around half of all fluorescent fittings in apartment buildings are emergency (they have a little red light on the side).

5. Replace T8 fitting with T5 fitting

Replacing the entire fitting with a new high efficiency T5 fitting can achieve cost savings of around 30%. The cost of a twin 28W T5 fitting starts at around $70, an emergency fitting starts around $170. T5 fittings are cheaper than the Chamaeleon LED but the energy savings are also much lower. Replacing entire T8 fittings with T5 fittings is typically the least cost-effective option to upragde fluorescent lighting but it is still an option worth considering if the aesthetics of the Chamaeleon LED fitting does not suit the area.

6. Occupancy sensors

Why replace tubes or fittings if you can just switch them off?

While not technically an upgrade to fluorescent fittings, in some instances installing occupancy sensors can provide superior energy and cost savings compared to all other upgrade options.

An good example is in storage sheds. Many car parks have caged storage sheds running along a wall of the car park with lighting running 24/7 even though the sheds are rarely used. Isolating lighting over the sheds from the main circuit and installing occupancy sensors can provide high energy savings

The installed cost of an occupancy sensor can vary from $250 to $600 depending on the type of sensor, area size and amount of re-wiring required. One sensor can control a whole bank of lights and research has shown energy savings of up to 80% can be achievable in low traffic araes.

Frequent switching of fluorescent lamps can significantly reduce lamp life. If you are going to install occupancy sensors you should also consider replacing the fluorescent tubes with LED tubes.

7. Voltage reduction (fixed dimming)

Fluorescent lamps require full mains voltage in order to “strike”, but once warm can operate at a lower voltage. For fluorescent lamps with magnetic ballasts energy savings of up to 25% can be achieved Voltage reduction works by lowering the voltage after the lamp has warmed up. It can achieve energy savings of up to 25% and typically results in a reduction in light output of 10%. Voltage reduction is typically not compatible with electronic ballasts found in relatively new fittings (less than 10 years old) and it may be compatible with control systems such as occupancy sensors.

Which option is best for my site?

Unfortunately there is no one solution to upgrade fluorescent lighting. Many suppliers will try to convince you that their option is the best way… and often it isn’t. The best option depends on the application, existing light levels, levels of occupancy, whether fittings are emergency or not etc… It also depends on your budget, the cheapest option in terms of upfront installation costs may not be the most cost-effective when taking into account operating costs, lamps life and maintenance costs.

We always recommend our clients seek quotes from a range of suppliers, and for a range of products.

Our energy audits give you unbiased, impartial advice. We do the calculations for you to determine installtion costs, energy savings, cost savings and payback for a range of options.

Energy Saving Certificates when upgrading fluorescent tubes

UPDATE – JUNE 2014

From the 1st of June 2014 retrofitting LED tubes or installing T8 to T5 converters into fluorescent tube fittings are no longer eligible to generate Energy Saving Certificates (ESCs). In NSW under the Energy Savings Scheme a change to the rule (Amendment No. 1 Rule 2014) means that installing T5 adaptor kits and retrofitting LED tubes are no longer valid activities under the Commercial Lighting Energy Savings Formula Method. This is effective for implementations on or after 1 June 2014.

Many companies are able to generate and sell ESCs when conducting many standard fluorescent tube upgrades. As an example, the enLighten Chamaeleon has been assessed for use in the Energy Saving Scheme. Replacing a standard twin 36W T8 fitting can generate around 4 ESCs, significantly reducing costs.

Emergency fittings

Many fluorescent tube fittings in apartment buildings are emergency fittings, these fittings have a battery back-up in case of power failuer. You can tell which are emergency fittings, they have a small red light on the side.

Many energy saving opportunites may not apply to emergency fittings. It is typically not recommended to retrofit LED or T5 tubes into an emergency fitting. It is also typically not recommended to install daylight or occupancy sensors to control emergency fittings. Voltage reduction units may not be compatible with emergency fittings.

The best energy saving option for emergency fittings is often to replace the entire fitting with a new emergency fitting. You can replace emergency fittings with either the Chamaeleon dimming LED emergency fitting with in-built motion sensor or a T5 fluorescent tube emergency fitting. The Chamaeleon is the more expensive option at around $300 to $350 compared for around $200 to $250 for a T5 fititng however the Chamaeleon has superior energy savings of 50% to 90% (depending on occupancy level of area) compared to savings of 30% by installing a T5 fitting.

Education is key to long-term success

It is important to educate stakeholders on the use and maintenance of energy saving technologies. The success of any energy saving measure is dependent on successfully managing the use of, and maintenance of equipment. It is vital to inform cleaners, maintenance staff, building managers and tenants of any issues. Clear signage should be installed on or around fittings to ensure they are maintained appropriately. If 36W T8 tubes have been upgraded with either T5 or LED tubes it is important that relevant persons at the site are aware of this and are properly instructed how to replace these tubes. T8 tubes will not physically fit into T5 fittings. Inserting a LED tube into a standard fitting without removing the starter may destroy the LED tube. A standard T8 tube may malfunction if inserted into a fitting that has been modified to accept either LED tubes or T8 to T5 converters.