Lighting
Tip 1 to 10 (10 total)
Consider discharge lighting in industrial applications
Capital cost for this is £60+ for a discharge fitting. The energy saving available is up to 50% if discharge lighting is chosen correctly, but an increase in consumption of up to 20% is possible if chosen incorrectly. When good colour rendering is not important (such as in certain industrial areas, warehouses etc), many forms of discharge lighting offer a practical energy saving alternative to fluorescent tubes. There are, however, limitations that must be borne in mind: As the energy savings figures imply above, there is considerable variation in the efficiency of the various types of discharge lighting. Fluorescent tubes are more efficient than certain forms of discharge lighting (particularly some mercury discharge lights). It is essential to choose wisely, checking manufacturers figures for bulb efficacy (light output per watt). Discharge lamps do not have the dimming capabilities of fluorescent tubes. The colour rendering is worse with discharge lamps than with fluorescent lamps (colours look unnatural with discharge lighting). As a rule of thumb, the higher the energy efficiency of the discharge lamp, the worse the colour rendering. Discharge lamps cannot be started with immediate full light output, rather they take a few minutes to warm up to full luminous flux. Thus they are not suited for applications with frequent switching. The above limitations demonstrate that only certain areas are appropriate for discharge lighting. However, if a continuous source of light is required in an industrial area with minimal daylight, discharge lighting can provide a highly energy efficient lighting solution.
| Aspect | energy efficiency |
| Sectors | my business, my community, public sector organisations |
Fit daylight-linked controls (photocells)
Capital cost is approximately £50 - £90 per sensor. The energy saving available is often around 40% in relatively bright rooms. Daylight sensors are used to adjust lighting levels according to the level of daylight the room is receiving. They come in two forms: Switching: these automatically switch off the lights when the level of natural light is adequate, and switch them back on when it is not. They cost approximately £50 to install, and can usually be applied to fluorescent and filament lamps. Dimming: these dim or brighten the lights according to the levels of natural light present. So, on a bright day the lights are dimmed right down (or even off), whilst on a dull day, the lights may be partially or fully on. Dimming sensors tend to be more expensive than switching ones, but, depending on the daylight distribution in an area, one sensor can often control a large bank of lights. All fluorescent and filament lamps can be connected to switching photocells. However, not all types of lighting can be dimmed. In areas of constant use, the dimming daylight linked controls are usually the best option, as lights switching on and off can distract ocupants, whilst lights dimming and brightening according to natural light levels tend to be imperceptible.
| Aspect | energy efficiency |
| Sectors | my business, public sector organisations |
Fit high frequency control gear (ballasts)
Capital cost is approximately £30 - £50 per fitting. The energy saving available is around 20%. When linear fluorescent luminaires contain high frequency electronic ballasts, energy consumption is around 20% lower than with conventional magnetic ballasts. There are also a number of other advantages: No flicker operation providing a more comfortable working environment. Longer tube life. Dimmable fluorescent lighting (assuming high frequency dimmable ballasts are bought). This enables the linear fluorescent lighting to tie in nicely with daylight-linked control, generating substantial energy savings. The capital cost of this measure is relatively high and, as a result, although the energy savings are significant, the payback period on the capital investment tends to be several years. However, should daylight linking be included, payback periods can be quicker.
| Aspect | energy efficiency |
| Sectors | my business, my community, public sector organisations |
Fit timer switches
Timer switches can vary from a simple switch set to turn lights off 5 minutes after they are turned on (useful in toilets and corridors, for example), to a comprehensive system controlling all the lighting in a building. Installing a timer control system can enable you to accurately control the building's lighting throughout the working period (for example ensuring all lighting is switched off at closing time, and in certain areas at lunch-time). Such timers are especially useful for areas where lighting is required over long, consistent periods.
| Aspect | energy efficiency |
| Sectors | my business, public sector organisations |
Purchase new high frequency reflector luminaries
Capital cost is typically £70+ per fitting. The energy saving available can be 50% or more (depending on current situation). Purchasing new luninaires can often work out to be more cost effective than 'polishing' an old luminaire. Certainly if refurbishing an area, new energy-efficient luminaries are a sound investment. Make sure the following features are present for maximum energy performance: High frequency ballasts (preferably dimmable). Reflectors: many luminaire manufacturers supply figures giving the light output from their luminaries: choose a light efficient one.
| Aspect | energy efficiency |
| Sectors | my business, my community, public sector organisations |
Remove a tube from luminaires and fit reflectors
Capital cost is free or £20 - £50 per fitting if reflectors are purchased. The energy saving available is often up to 50%. If a room is brighter than necessary, it makes sense to reduce the light levels by removing a tube or two from the fluorescent fittings. A reflector can boost the light output of a luminaire considerably. It is often possible to obtain retrofit reflectors for luminaires, boosting the light levels enough for a tube to be removed.
| Aspect | energy efficiency |
| Sectors | my business, my community, public sector organisations |
Replace 38mm Fluorescent tubes with 26mm tubes
The cost of a T8 fluorescent tubes is typically £0.50 to £2. The energy saving available is approximately 8%. Replacing T12 tubes (38mm / 1.5" diameter) with T8s (26mm / 1" diameter) is a very simple measure that offers exceptionally good energy savings for the minimal capital investment required. T8s are available in the same lengths as T12s (apart from the largest 8ft T12 length), tend to be cheaper than their equivalent T12s, and will usually slot into the same light fittings.
| Aspect | energy efficiency |
| Sectors | my business, my community, public sector organisations |
Replace standard lightbulbs with low energy CFL bubs
Capital cost is typically £2 - £5 per bulb. The energy savings available is around 80% over standard bulbs. You should aim to remove as many standard light bulbs as possible. Low energy compact fluorescent (CFL) bulbs have been on the market for some time. Although compact fluorescent bulbs cost considerably more to buy outright, they use around 20% of the energy of standard bulbs, and last around 8 times as long. The payback period for installing low energy lighting is typically less than one year. Low energy bulbs are available in bayonet or screw fittings and in wattages to give the light output of all the standard bulb range. You should especially aim to install low energy lighting in areas that have frequent occupancy or where lights are left on for long periods of time.
| Aspect | energy efficiency |
| Sectors | my business, my community, my household, public sector organisations |
Use discharge lighting for floodlights
Capital cost is £5 - £30 for bulbs and typically £60+ per fitting. The energy saving available is up to 80 or 90% if the most efficient discharge lights are chosen. Floodlights are expensive to run, especially when they are left on for long periods. Discharge lighting is not suitable for motion activated lighting (as the bulbs take a while to warm up), but when security lighting is left on for long periods, such as in a carpark, the replacement of tungsten halogen floodlights with discharge lighting gives impressive savings. The most energy efficient discharge lighting tends to be high-pressure sodium, although it is worth comparing the efficacy of bulbs (the light output in lumens per watt of power consumed) before purchasing.
| Aspect | energy efficiency |
| Sectors | my business, public sector organisations |
Use tungsten bulbs with an infra-red reflective coating
Capital cost is around £4 - £5 per bulb (a little more than regular bulbs. The energy saving available is around 30%. If interior tungsten halogen bulbs are necessary for the lighting effect they create, then they can be replaced with equivalent bulbs with an infrared reflective coating (IRC). If the lights are on for around 2000 hours per year (typical 9 - 5 operation), payback will usually be between 2 or 3 years (payback will be quicker for longer hours). It is always economic to purchase IRC bulbs when standard tungsten halogen bulbs are due for replacement.
| Aspect | energy efficiency |
| Sectors | my business, public sector organisations |