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ILE Statement on the Replacement of GLS Lamps with Energy Efficient Light Sources The Government is currently seeking to reduce carbon emissions by looking at the efficiency of different energy consuming products. The current proposals review eleven different areas, including domestic, commercial, and street lighting. A major part of the proposals for reducing the use of electrical energy for domestic lighting involves the replacement of the traditional shaped GLS lamp (commonly referred to as a bulb) with energy saving alternatives such as the compact fluorescent lamp (CFL) which provide energy savings of around 80% or energy saving tungsten halogen lamps which can save between 20% and 50% in energy use. This statement examines the benefits and disadvantages of this proposal and is limited to lamps designed to be a direct plug-in replacement for existing traditional shaped GLS lamps. The use of these alternatives provides a simple and easy means by which we can all help to reduce our carbon footprint and help to protect the world. Do CFLs provide the same level of lighting as GLS lamps? Most GLS lamps provide approximately 11 to 13 lumens of light per watt of energy consumed -- so a 60W clear or pearl GLS lamp produces approximately 700 lumens (softone lamps produce 600 lumens) of light and a 100W GLS lamp produces approximately 1,300 lumens (softone lamps produce 1,200 lumens). In comparison an 11W CFL, with their softone appearance, produces approximately 600 lumens and a 20W CFL produces approximately 1,200 lumens. The comparison with a softone lamp is accepted by Trading Standards and must be marked on the packaging. As with GLS lamps, CFLs age, and their light output falls so that by the time they have burnt half their life, their output will be considerably lower at about 80% of their initial output. This reduction in light output will continue as the lamp ages and should therefore be considered when deciding which wattage and output CFL to use. Do CFLs provide the same quality of light as the GLS lamp? A GLS lamp has a correlated colour temperature (CCT) of 2,800K and a colour rendering index (CRI) of 100. The higher the colour temperature, the colder the appearance of the light produced. The closer the CRI is to 100, the better the colour rendering of the light source. The GLS lamp therefore has a warm CCT and very good colour rendering properties. While CFLs come in a number of colour temperatures, those generally used in domestic situations are classified as Warm White with a CCT of 2,700K and a CRI of 82. In this example the colour temperature is very similar to that of the GLS lamp and little difference will be noticed. However, as the GLS lamp has a better CRI, it will reproduce most colours accurately, whereas a CFL will distort some colours due to the non-continuous wavelengths of the light produced. Where colour rendering is of importance energy saving tungsten halogen alternatives may be used. Another light quality issue concerns the size of a CFL lamp. As the filament of a GLS lamp (with a clear glass envelope) is quite small, it produces relative strong shadowing, interesting areas of light and shade in the interior and a degree of visual ‘sparkle’. However, as the CFL lamp is quite a large light source, by comparison, it produces no distinct shadows and creates rather a flat, bland lighting effect which many people find visually unsatisfactory. Where distinct shadows and visual sparkle are of importance energy saving tungsten halogen alternatives may be used. Do CFLs use less energy? A GLS lamp will use approximately six times the energy of an equivalent CF. Therefore a CFL shows a considerable reduction in the energy consumed and metered at the domestic premises. Domestic CFLs have a low power factor and thus a higher lamp current which will result in higher losses in the power distribution system but energy savings are still achieved. This effect does not affect energy saving tungsten halogen lamps. The Government are appointing independent experts to evaluate the true energy savings to be gained from converting to CFLs and other energy efficient light sources. The electronic circuitry in CFLs can also cause high levels of distortion to the electricity supply which may have adverse effects on other electrical equipment. Fortunately the electrical load from CFLs in a domestic situation is small in comparison to the remainder of the electrical load, so these effects are substantially reduced and should not cause problems. In installations with large quantities of CFLs it is possible that this distortion may affect other equipment and care may be needed but no practical problems have been experienced in such installations. Do CFLs take a long time to reach full brightness? GLS lamps provide almost instantaneous light when switched on whereas CFLs do not start instantaneously and require a short time to strike – they also take even longer to run up to their full light output (the current estimated starting time is that they reach 60% of their rated light output in one minute). This delay may cause problems in some domestic installations where light is required instantly, for example on stairs in the middle of the night or in cupboards or storage areas, where the user is looking for something in a hurry. It is obviously unsatisfactory to have to wait for the light to switch on and run up to full brightness. Where a long wait for run up to full brightness is not acceptable energy saving tungsten halogen alternatives which have an instantaneous run up may be used. Are CFLs financially subsidised? Many CFLs are subsidised by the electricity companies to help reduce the need to invest in new generating, transmission and distribution systems; similarly, other environmentally aware organisations also subsidise these lamps to help protect the environment. Both strategies are to be welcomed and applauded – but will these subsidies remain once a high percentage of users have committed themselves to the use of CFLs, and the GLS alternative is no longer in production? Do CFLs have any adverse health risks? A number of organisations dealing with specific medical conditions have concerns over the quality and consistency of the light output from CFLs. The majority of these complaints are concerned with: • The quality of the light (i.e. the colour rendering and the colour reproduction of the light) both of which can be varied in production to suit different requirements, albeit at a cost. • The effect of ‘flicker’ in the light output -- a long-standing criticism of fluorescent and discharge lamps. In fact, this has potentially been overcome by the use of high frequency control gear, which moves the frequency of ‘flicker’ to well above the limits normally considered a problem to the human visual system. • The intensity of the light – CFLs, especially the exposed tube type, have a higher surface brightness than comparable output GLS lamps. However, this can be offset to a large extent by the use of lamps with an external outer frosted envelope, which gives the lamp an appearance similar to conventional GLS lamps. Do CFLs last longer? GLS lamps have an average rated life of 1,000 hours compared to the average rated life of a CFL of 8,000 hours. A light in one of the principal family rooms, such as a living room or kitchen, will be used for approximately 1,000 to 2,000 hours per annum. Frequent switching on and off of a CFL will reduce its life and it is recommended that CFLs should always be run for a minimum of 15 minutes each time they are switched on, to minimise the effect of switching on the lamp life. Are CFLs more economic? Approximately 90% of the energy consumed by a GLS lamp is produced as heat which is often classified as ‘waste’ heat (i.e. 55W of the energy consumed by a 60W GLS lamp or 90W of the energy consumed by a 100W GLS lamp is produced as heat not light. In an average UK domestic property this heat will actually contribute to the heating of the surrounding room and technically reducing the amount of heating required. However the actual effect of this additional heat will vary dependent upon the location of the lamp and the type of control systems used on the heating system. This heat may be a nuisance on very hot summer’s nights or where the property is so well insulated that it needs air conditioning to maintain a comfortable temperature. In most other domestic situations, the heat from GLS lamps may not be wasted and may help to offset the heating supplied by the central heating system. Are there any disposal problems with CFLs? Modern GLS lamps can safely be recycled or disposed of as there are very few dangerous materials used in their manufacture. Older GLS lamps used lead in the solder but this has now been replaced with other materials. CFLs do use small amounts of potentially dangerous materials in their manufacture, such as mercury. Although the mercury content is about the size of a pin head, with the massively increased use of CFLs across the country, there will be an increase in mercury into landfill following disposal of the lamps. This would not occur if CFLs were disposed of by recycling to recover the mercury, phosphors, and other materials used in their manufacture. Unfortunately, while it is a requirement of the WEEE Regulations to recycle lamps, discarded GLS and CFL lamps placed in domestic waste will not be recycled but generally disposed of into landfill. . This increase in mercury due to disposal is more than offset by the reductions of mercury that would have been emitted from fossil fuels burnt by power stations supplying the extra power for GLS lamps. The consumer should have no problems from the disposal of old lamps provided they are not broken. Where CFLs are broken there is a very small possibility of ingesting the phosphors and mercury but this can be minimised by sensible precautions, such as not breathing in any of the powders from the broken lamp. Care should be taken when dealing with either a broken GLS lamp or CFL not to cut oneself on the glass or resulting sharp edges. Will CFLs fit my existing light fittings? Many CFLs are larger than comparable GLS lamps and therefore may not be able to fit into fully enclosed light fittings -- or may protrude out of the light fitting, as can be seen in many retro-fit installations. However, manufacturers are taking account of this, so CFLs are shrinking in size, and new shapes of lamps are available which mimic existing GLS lamps, as well as candle lamps and golf ball lamps. Unfortunately such lamps generally are only available at the full retail price, making them expensive in comparison with GLS lamps and are often only available in a single wattage. Can CFLs be dimmed? GLS lamps can be varied in output from 0 to 100% using simple voltage reduction devices in place of the wall switch. This high degree of variability allows the level of lighting for the specific task to be readily set, or the ambience of the room to be varied and changed to suit the mood of the occupants. The level of light produced by a GLS lamp is roughly proportionate to the energy consumed and paid for. CFLs cannot be readily varied and need to have specialist control units fitted or need to be of a special design. The year 2007 also saw the limited introduction of new CFLs by such companies as Varil-Lite and Megaman, which can be dimmed on conventional rotary dimmers. However, the energy consumption of a CFL when dimmed down is not always in direct proportion to the energy consumed -- for instance when varied down to 50% light output the energy consumption could be approximately 60% of the rated consumption or even higher. So you will be paying more for each lumen of light produced. Can I use CFLs with electronic timers or electronic sensors? Many of us have got used to having lights on electronic sensors or time switches to switch on or off at pre-determined times, or to specific lighting levels, to detect intruders. Unfortunately many of these control systems are not compatible with standard CFLs and may be destroyed by the switch on current from the lamp. As the sales of CFLs increases, suitable equipment is becoming available -- but care should still be taken to ensure that permanent damage, or fire, cannot be caused by retro-fitting CFLs in GLS lighting systems controlled by electronic equipment. The effect of age on lamp characteristics GLS lamps tend to fail just before the reduction in light output through life is noticeable. As CFLs approach old age their light output drops significantly, the run-up time to full output becomes extended and the presence of flicker becomes more noticeable, however, newer types of CFLs do not suffer from flicker. Were flicker is a problem energy saving tungsten halogen alternatives up may be used. Are there any other energy-efficient replacements for GLS lamps? The pressure to reduce energy consumption has increased the development of alternative light sources. It is anticipated that within two to three years alternative light sources, such as LEDs, will be available to replace GLS lamps. Some of these lamps may have advantages over the CFLs currently available – however, the rapid development, and improvement, of CFLs will continue to reduce many of the adverse features of these types of lamp.
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