Lighting costs can account for between 50% and 80% of onsite electricity bills for warehouses, logistics and distributions centres. These buildings are usually large, open spaces that require enough light to allow staff to navigate safely between aisles reducing the risk of accidents and damage to stored items – which results in a great deal of energy being used for lighting.
By installing new energy-efficient lighting, it’s possible to save up to 80% on electricity bills, without compromising the brightness of the lighting, and in some cases improving it. This is because old systems of lighting are based on older lighting technologies (such as older fluorescent strips) which do not have the efficiency of more modern systems using LEDs and newer fluorescent products. It’s also possible that areas of the building are being lit at full strength when it’s not required, and lighting is left on and is not sensitive to whether or not people are actually working in the area.
Old Lighting Types
An older warehouse lighting set-up will comprise of several ‘low bay’ or ‘high bay’ lighting fittings using high intensity discharge (HID) light bulbs rated at either 250 or 400 Watts. The HID bulbs are either metal halide (a bluish-white light) or high pressure sodium (a yellow-peach coloured light) and are usually fitted at 5 metres or higher from the ground. Older fluorescent strips using T8 or T12 tubes are more likely to be fitted at lower levels.
Problems With Older Lighting
Energy losses with older lighting systems are significant:
- Older HID and fluorescent lights have additional energy requirements for their magnetic control ballasts meaning an extra 5-20% of electricity is required
- Light ‘loss’ in older fixtures – older fixtures often cannot direct light where it is needed, resulting in poor lighting of work surfaces. This is often compensated for with additional (expensive) light fittings to achieve the needed lighting level.
- No control of light levels – older systems often have a default setting of full on during working hours. The lights are limited to being off or on as older HID and fluorescent lights cannot be dimmed or switched off or on in response to either movement or existing daylight. This means energy is being wasted.
When the energy lost is added up from these three areas, the annual wasted energy in a typical warehouse can run to many thousands of pounds. It has been demonstrated that using the latest energy-efficient warehouse lighting systems that deal with the above problems, can save up to 80% in energy costs.
Energy-Saving Warehouse Lighting Systems
New well designed warehouse lighting systems that use the latest technology light sources (including the T5 fluorescent tube, induction lamps and LEDs) and intelligent control systems can not only cut the energy bill by 80% but also improve the quality of light. The improved productivity and well being of staff in appropriately lit spaces is well documented, and it also contributes to improved health and safety.
Lighting Options for Warehouses
The new lighting technologies available for lighting warehouses include:
- T5 fluorescent tube fixtures – these use 2,4 or 6 T5 tubes mounted in a light fitting with reflector to direct all the light downwards. These tubes work on the same principles as the older T8 & T12 tubes, but are much more energy efficient and have an electronic control ballast and a longer operational life of between 12,000 and 18,000 hours.
- Induction lamp fixtures – induction lamp technology is similar to fluorescent tube technology, but works by creating an electromagnetic field around the tube – rather than passing an electric current through the tube. Induction lamps have a very long life (up to 100,000 hours) and produce high quality white light.
- LED lighting fixtures – LED lighting is improving in leaps and bounds and with it’s long life (between 50,000 and 80,000 hours) and the ability to use it in a variety of ways including producing strong unidirectional lighting, this is rapidly becoming the preferred type of lighting for most industrial usage.
All the above technologies have the ability to be dimmed and switched instantly, unlike the older warehouse lighting solutions. This means they can be used in advanced lighting control systems, where only specific aisles are lit according to occupancy (either through motion or acoustic monitoring) meaning that aisles are only lit to full brightness when in use. It is also possible to implement dimming control according to existing daylight so that a constant illumination level is maintained, but if the warehouse has daylight from say skylight panels, the electric lighting is balanced meaning energy consumption is reduced at the times of day when daylight is strongest.
Benefits of New Warehouse Lighting
- Lower maintenance costs – new bulbs have 6-9 years continual operation which vastly reduces the maintenance cost of replacing bulbs
- Government financial assistance – due to the level of energy and carbon saving, new warehouse lighting could qualify for Carbon Trust financial assistance
- Improved light quality – new lighting technologies can emit light that is close to daylight which means a safer working environment and better colour recognition for product picking
- Improved light distribution – older warehouses often suffer from problems such as shadows between high shelves making it difficult for workers to read labels and pick products efficiently
- Sustainable and energy efficient – energy saving warehouse lighting provides one of the most effective ways of reducing the carbon footprint of a business and delivering on environmental and social responsibility commitments.