Over the last few years we have seen many organisations

taking a more realistic view of what their building services

plant actually costs them. Rather than simply looking at

the initial capital costs, whole life costing considers the

costs to the organisation throughout the life of each piece

of equipment.

This is a particularly sensible approach to take with lighting,

where whole life costs can be very significant. In particular, the

choice of light sources during the design phase of a new build or

refurbishment project can have a major impact on the running

costs of the building.

In taking this holistic view, it’s essential to consider all of the

factors that contribute to cost – and as many of these are absorbed

in day-to-day activities they often go unnoticed. The cost of the

lamps and the energy they consume are obvious things to consider.

But it’s also important to take account of the cost of replacing

lamps, the disruption the re-lamping might cause and the health

and safety implications of accessing light fittings at height.

In most office spaces these concerns are addressed through the

use of modular ceiling fittings using linear or compact fluorescent

light sources (CFLs) – a solution that works very well in most

cases. Very often, this is combined with a bulk re-lamping schedule

so that all of the lamps are replaced in one go, towards the end of

their useful life. And if a lamp or two blows before the bulk

replacement is due, it is unlikely to make much difference to the

overall lighting levels.

In other areas, however, things may not be so simple. In a retail

environment, for example, failure of one of the lamps in the display

lighting will detract from the visual impact of the goods on display

so there is a strong incentive to replace failed lamps immediately.

Similarly, if a light fails on a stairwell there are health and safety implications so, again, the lamp needs to be replaced pretty quickly.

In these situations, where almost immediate replacement is

required, the whole life costs associated with that lighting multiply

at an alarming rate. It’s not like at home where we can grab a stepladder (or even a chair), nip up and change the lamp.

Accessing any light fitting that is mounted at height falls within

the Work at Height Regulations 2005, which came into force last

April. And ‘height’ is defined as any situation where a person could

be injured by falling – which accounts for accessing virtually any

light fitting. This means that anyone undertaking this work has to

have received training in working safely at height and they need to

have equipment that will minimise the chances of a fall.

Consequently, only certain members of the building operator’s

maintenance staff, or sub-contractors if they are used, will be able

to carry out re-lamping. Frequently, they will have to be called away

from other jobs, which has a knock-on effect for other areas of

maintenance and overall labour costs.

In all situations, they will need to carry out a risk assessment and

take measures to minimise the risk of injury to themselves and to

others. Returning to the retail display lighting example, a stepladder will probably be an acceptable form of access but it will be necessary to cordon off the area to minimise risk to shoppers, if the work is carried out when the shop is closed, there will be premium rates to pay for out of hours work.

In addition, any such work attracts paperwork to show that the

necessary risk assessment was carried out, eating into the

administration time of expensive managers.

All of which creates a strong argument for selecting light sources

that will provide long life, so that re-lamping cycles are extended

and the associated costs are minimised. And it is in this area that

specifiers need to look beyond the traditional uses of fluorescent

lighting to make better use of the new compact fluorescent lamp

technologies that are coming onto the market.

One of the problems with fluorescent lighting is that it’s been

around for so long that people tend to take it for granted and not

notice how it has evolved. For instance, there is now a new compact

fluorescent technology known as Ingenium that provides a life of

15,000 hours with higher luminous efficacies and shorter preheating

times than earlier.

Staying with the retail example for a bit longer, many shops still

use halogen spotlights for their display lighting, as these are wellsuited for directing the light precisely onto the merchandise.

Unfortunately, most halogen lamps will only last for 1000 to 2000

hours – not very long in a shop that has extended opening hours.

An alternative is to use compact fluorescent spotlights that have

been designed to replace conventional incandescent spotlights by

using the same lamp base and having similar dimensions. Not only

do these lamps last a lot longer, they also consume less energy. For

example, a 9W CFL using a GU10 lamp base and an integral

reflector to control beam width can be used as a direct replacement

for a 40W GU10 halogen lamp. These lamps also include a glass

diffuser to provide a smooth and even distribution of light.

Offering similar benefits are CFL reflector lamps designed to

directly replace R50, R63, R80 and PAR30 spotlights, all providing

significantly reduced heat output as well as the cost of ownership

benefits outlined above. For retail outlets, where high numbers of

spotlights are used for display lighting, this benefit can help to

provide significant reductions in air conditioning costs. And,

because the latest CFLs use improved phosphor mixes,they provide excellent colour rendering, so there is no need to compromise on the quality or impact of the display lighting.

Lighting at height in public areas is clearly another area where

lamp life is an important consideration, and this is particularly true of decorative ‘fairy’ lights because there are so many lamps

involved. In Leeds, for instance, there are at least 40,000 lamps in

use for a variety of decorative purposes at any one time, with many

more around the Christmas period.

Many of these lights have recently been changed from conventional incandescent ‘fairy’ lights to ‘golfball’ CFLs in a range of colours.As well as increasing lamp life by up to 15 times, these

lamps use around 70 percent less energy while providing a higher

light output.

In this case, another criterion that came into play was the

likelihood of damage to the lamps – either accidental or deliberate.

To minimise this problem, the golfball CFLs are sheathed in a

silicone sleeve to provide much greater impact resistance, and if

any lamps are broken the glass fragments are retained within the

silicone sleeve. As a result, lamp breakages have been reduced

from 40 percent to less than five percent.

There are many other areas where CFLs are making their mark,including smaller decorative light sources such as candle lamps,as well as replacements for standard GLS lamps.

When CFLs were first introduced with BC and ES lamp bases they

were designed as a retrofit for GLS lamps but the high light output

from the fluorescent tubes tended to cause discomfort glare and

limited the use of these lamps. Newer GLS-replacement CFLs

incorporate a glass bulb around the tubes to minimise glare while

retaining very similar dimensions.

Nor has the development of CFLs stopped with the introduction

of more compact designs, new lamp bases, directional reflectors

and glass envelopes. CFL manufacturers have also gradually been

increasing the light output and wattages of their offerings and there

are now CFLs with wattages up to 300W, providing a light output of

24,000 lumens. These advances have been achieved by increasing

the number of tubes in each lamp and improving the performance

of each of those tubes – opening up areas such as low-bay lighting

and floodlighting to CFLs.

The examples discussed here just touch the surface of the potential for compact fluorescent light sources in a diverse range of applications. There are no other types of light source that offer the

same versatility with high energy efficiency and long life. So now is

the time to take a closer look at how CFLs can help to minimise the

whole life costs of lighting.

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