Delamping vs. Other Lighting Upgrades
Rather than delamp, you could:
- Replace your whole light fittings with more efficient fittings
- Use a "T5 Adaptor" and replace both existing T8 tubes with T5 tubes
Below we compare the costs/benefits of these options as compared with delamping for a typical double 120mm (4') fluorescent fitting.
|Option ||Delamp + New Tube and Mirrorlux Reflector ||Replace both tubes with T5 28 watt tubes and T5 Adaptors ||Replace fitting with high efficiency 36 watt fitting with electronic ballast |
|Energy Savings ||50% ||30% ||55% |
|Installed Cost ||$40 ||$70 ||$300 |
|Typical annual energy savings ($) ||$20 ||$14 ||$22 |
|Payback (years) ||2 ||5 ||14 |
|Ease of install? ||Easy ||Complex ||Complex |
|Reliability? ||High ||Unreliable* ||High |
|Lamp replacement cost? ||Low Cost ||Expensive ||Low Cost |
|Long lamp life? ||Long ||Short* ||Long |
|Is it EMF compliant (electromagnetic interference)? ||Yes ||No* ||Yes |
|Disposal of previous fitting? ||Only 2 tubes to dispose of ||Need to dispose old tubes plus power factor correction capacity, which may contain PCBs ||Need to dispose of entire fitting|
* Based on statements by Osram.
As can be seen delamping is the most cost effective whilst still providing large energy savings.
Contrary to popular option, T5 lights are not necessarily more energy efficient than a T8. In fact, a comparison of fluorescent lighting technologies at www.energyrating.gov.au shows that:
- The best 36 watt T8 produces 51% more light than the worst 28 watt T5.
- The total light output of the best 28 watt T5 tube on the market is only slightly better than the worst 36 watt T8.
- Replacing a good 36 watt tri-phosphor T8 with a good tri-phosphor 28 watt T5 will result in both a reduction in energy consumption – and a drop in light output.
T5s are best used in new high efficiency fittings.
Delamping vs. Other Investments to Reduce Carbon Emissions
What's really exciting about the reflectors is the excellent return on investment you get. Let's say you have $10,000 to invest on measures to reduce your carbon footprint. Ten thousand dollars would buy you:
- A 1.5 kW grid-connect solar photo-voltaic array on your home, after the government rebate of $8,000 (otherwise it would cost around $18,000).
- Two large domestic solar hot water systems installed on two homes.
- Around 550 Mirrorlux Reflectors, for installation in your office, school, shop, hospital, and more.
Out of those three choices, which one provides the greatest greenhouse savings, and what is the annual return on investment that each of these investment provides? The table below illustrates the savings for each.
|Your $10,000 investment ||Amount of money saved each year* ||Tonnes of greenhouse gas saved each year (tonnes CO2-e)* |
|A 1.5 kW solar photo-voltaic array on your home, AFTER the government rebate of $8,000 ||$372 ||2.9 |
|Two large domestic solar hot water systems installed in two homes, replacing electric hot water systems ||$941 ||7.3 |
|Around 550 Mirrorlux Reflectors, for office, school, shop, hospital, etc installation ||$9,583 ||74.7|
* Assumes a tariff of $0.17/kWh and power used in Victoria. For the solar PV array assumes the equivalent of 4 peak sun hours per day. For the solar hot water system assumes an electric boost system on a home with 3 or more bedrooms with annual saving of 2,767 kWh/year per system, as reported by Sustainability Victoria (Estimated Household Water Heater Energy Use, Running Costs and Emissions, Victoria, 2005). For the office assumes 10 hours of light operation/day, 5 days a week, 50 weeks a year a year.