Posted by: Nigel Collins
Some of our clients are starting to see the benefits of investing in LED lighting, not only as a way of reducing their electricity costs, but in some cases, improving their working environment. For the office, the almost daylight whiteness and elimination of flicker that can be experienced with fluorescent tubes is an immediate visible benefit. For hotels and restaurants where ambience may be required, warm whites are available.
So what is the business case for LED lighting?
The ROI on LED lighting will vary depending on the type of lamp so for example, replacing a number of 50w GU10 Halogen with 5w LED lamps will show a 90% energy saving. At the other end of the scale, a T8 36w 2ft fluorescent tube, even with ballast losses will only consume about 40w so replacing with an LED equivalent of 15w will show a 62.5% energy saving. The fairly minor wiring modifications required to bypass the ballast will nevertheless need to be undertaken by a qualified electrician.
Lower maintenance costs can add to the financial case. For example, manufacturers typically quote 15,000 hours as the life of a fluorescent tube. This may of course reduce depending on the frequency of switching on and off. Equivalent LED tubes have a life of 50,000 hours and without the need for replacement ballasts or chokes. Many organisations only replace lamps as they start to flicker or burn out so the unit cost of replacement is quite high.
When surveying a site, it is important to consider the number of running hours. A main office might be in use for 10 hours/day, 5 days a week but there may be side meeting rooms where lights are off for much of the day. The best ROI can be found in 24/7 operations such as in hotel foyers and on garage forecourts.
As well as the obvious reduction in carbon, when fluorescent tubes are replaced, mercury has to be extracted and disposed of. LED equivalents do not contain these contaminants and have a much longer life.
The case for Re-lamping
Whilst in new build and major refurbishments, it can make sense to install new LED fittings and architects are already embracing the technology, the major opportunity is in re-lamping. In some cases however, it’s worth considering replacing modular luminaires (which typically house four fluorescent tubes in housing, complete with reflector), with replacement flat panels. These have much cleaner lines and as the LED tubes offer directional light, have no need of reflectors.
Now the common mistake is to select products based on price. Whilst price is important, product quality is more so. ROI might typically be as long as 2 to 3 years so if products fail due to sub-standard circuitry, poor design or failings in quality control, the financial case falls apart. It is rarely the LEDs that fail but the reliability of the circuitry is very dependent on adequate heat dissipation. As with many products, the market is being flooded with cheap imports from China and if product is being sourced from China, you need to be assured of batch consistency and quality control. One of the market leaders who we recommend now manufacture all of their LED tubes in the UK.
Product guarantees are important and whilst 3 year warranties are common and may give some reassurance, you have to be confident in the product as, based on a 50 hour working week, 50,000 hours is equivalent to over 19 years.
The other issue with the quality of the product is that the amount of light emitted can vary significantly. Light emitted is measured in Lumens but the density of light on a surface is measured in Lux (Lumens per square meter). It is important to understand that a lower beam angle can enable a manufacturer to quote higher Lux values for the same light output.
Another consideration with supplier selection may be whether their product qualifies for enhanced capital allowances.
Energy efficient lighting has in the past had a bad name as some compact fluorescents entering the domestic market were of poor quality and we should still be wary. A trial area should be selected for a pilot project before committing to large scale re-lamping.
Auditel can offer to undertake surveys, assess the financial case and recommend suitable suppliers. Please contact the author of this article, Nigel Collins for more details.