Lighting energy efficiency

For health and safety reasons it's a legal requirement to provide adequate lighting in a workplace. Appliances and fittings must be safe, and lighting levels must be good enough for people to work and move around safely.

Good lighting systems also enhance a business space for both staff and customers and can be used to create a specific effect. For example, using lighting in a shop to highlight selected displays helps to attract customers to particular goods.

However, using higher than recommended lighting levels can be counter-productive. Areas that are too brightly lit can be uncomfortable to work in because of the glare.

Reduce the need for lighting

Lower lighting levels can make working areas more comfortable and also help to reduce energy costs.

You can reduce lighting levels by:

• making good use of natural light - switch lights off and keep windows and roof lights clean and clear
• reducing the number of lights in over-lit areas - think about removing some lamps from their fittings

Use blinds to maximise daylight

Blinds can be used to enhance natural daylight instead of blocking it out, meaning that electrical lighting can be reduced or switched off. Horizontal blinds can re-direct daylight onto ceilings and higher walls, brightening the whole of the area while protecting those near windows from heat and glare.

Good housekeeping saves money

Encouraging staff to use lighting systems more efficiently can play a large part in achieving savings. Many adjustments can be made straight away and cost little or nothing. You could:

• introduce an official policy for switching off lights - remind staff to do this with stickers above switches
• put labels on light switches to help staff identify which lights to turn off in unoccupied areas
• set lighting controls to switch lights off during periods when workspaces are unoccupied
• get staff involved in lighting energy efficiency campaigns - ask them for feedback on problem areas
• train staff to use controls to create their own comfortable and efficient working conditions

Lighting has an important role to play in:

• providing the correct amount and type of light for your business operations to be carried out safely and efficiently
• creating the right atmosphere for your staff and customers

Different types of business have different lighting requirements, depending on their premises and business activities. When you're designing your lighting system, give thought to:

• safety - potential hazards need to be lit, including emergency escape routes
• business activities - lighting levels at workstations need to be adequate, including how colours will appear (colour rendering)
• comfort - try to avoid problems with glare
• occupancy levels - work areas may not need to be lit all the time

Select the best lighting for your business sector

Lighting systems are made up of three elements:

• the lamp (or light bulb)
• the luminaire (the fitting that includes the lamp)
• the controls (either manual or automatic)

To benefit from maximum energy savings, it's very important to choose the right lamp. Each type of lamp gives light of a different colour, brightness and warmth. Lamps also have different characteristics such as efficiency and life.

Using the most appropriate energy saving lighting systems for your business requirements can result in lower running costs and less maintenance, as well as improved light quality.

Ensure lighting matches the building layout

If the use of your premises changes, or you alter the layout of the building, it's important to remove any lighting that's no longer needed. Disconnect lights that are blocked by equipment or shelving and not required any more. Try to make sure that switches are located in the same room as lighting where possible.

There are three main types of lamp, each of which creates light differently:

• filament lamps - the filament has a high resistance to electricity and produces light when it gets so hot it glows
• discharge lamps - an electrical charge applied to a gas-filled lamp makes the gas produce energy in the form of light
• LEDs (light emitting diodes) - a pure semi-conductor produces light in response to an electrical current

Different lamps produce light in different ways and suit different tasks. When you design or refurbish a system, choose the lamp type that gives the right light quality at the lowest lifetime cost.

In most business settings, LEDs are now the first option to assess because they are efficient, controllable and long-lasting. Legacy lamp types may still appear in older installations, so plan upgrades carefully.

Filament lamps

Traditional filament lamps (incandescent and many halogen types) switch on instantly and can render colour well, but they are usually inefficient and expensive to run.

If you still use them for spotlighting or display, check whether an LED replacement would give the same effect with lower running costs and less heat.

Discharge lamps

Discharge lamps include fluorescent and some high-intensity lamps (such as sodium and metal halide). They can be efficient, but many older types are being replaced by LEDs because LEDs are easier to control and maintain.

If you are upgrading, check compatibility with existing fittings and plan safe disposal of old lamps and control gear.

LEDs

LEDs are efficient, switch on instantly and can last a long time when specified well. They work well with dimming, sensors and zoning, which helps you avoid lighting empty areas.

When specifying LEDs for general lighting, check glare control, colour quality and the suitability of drivers and controls.

Energy efficient lamps

If you use fluorescent tubes you can make significant energy savings by switching to slimmer tubes. For example, if you replace T12 tubes (38 millimetres diameter) with T8 tubes (26 millimetres) you can make savings of 10 per cent. Switching to T5 tubes (16 millimetres) brings even greater savings while keeping a high light output.

No matter how efficient lamps are, energy is wasted if lights are on when they don't need to be. There are different types of control that allow you to maintain correct lighting levels while keeping your energy usage as low as possible.

Zoning lighting

Zoning lighting can be used in large workspaces which need different levels of lighting. Creating separate, independently controlled zones means that you can switch off or dim lights in certain areas and increase it in others. For example you could switch off lights near windows to take advantage of natural daylight, but keep them on further into the room.

Installing zoning controls can be appropriate where there are:

• variations in occupancy levels
• individual workstations which need brighter light
• different levels of daylight provision

Install and use occupancy sensors

Occupancy sensors switch off lights automatically when a space isn't being used and can reduce lighting costs by up to 30 per cent.

Install and use daylight sensors

Daylight sensors - or photocells - switch off or dim artificial lighting when there's enough daylight. They are particularly useful for external lights, and can pay back their costs within a year. You can combine them with time switches to make even greater savings.

Install and use timing controls

Installing a seven-day timer can help to create a specific lighting pattern for your premises. You can use timers to set lights to come on at different times of the day throughout the week, saving energy that would otherwise be wasted in lighting unoccupied areas. Some timers have multiple on and off switch times for added flexibility.

Time delay controls are also useful in certain situations - for example to switch off lights in cupboards and storerooms automatically.

Keeping your existing lighting systems well maintained can improve lighting efficiency and reduce costs for your business by up to 15 per cent.

Lighting cleaning schedule

The first step is to put in place a cleaning schedule as part of your regular maintenance. Make sure your cleaning schedule covers:

• windows and skylights - regular cleaning lets maximum daylight into the building
• light fittings and lamps - keep these free from dust and dirt which can reduce the light they give
• sensors and controls - cleaning these regularly makes lighting systems more effective, particularly systems with automatic dimming controls

Lighting maintenance schedule

A regular maintenance programme can lead to energy savings as well as improving light quality. Setting out your programme in a maintenance schedule means that you won't overlook anything. Start by going round your lighting system and noting:

• what equipment needs to be maintained
• the light levels in each area
• any issues or problems with lighting or equipment

Then draw up a schedule identifying each maintenance activity and setting out how frequently it should be done.

As part of your regular maintenance programme:

• check that sensors and timers are working correctly, with settings matched to the way your business operates
• replace blackened, flickering, dim or failed lamps
• consider installing alternative, more efficient lighting systems

Energy-efficient lighting options are improving all the time and can be used to replace almost all traditional lamps. Upgrading your lighting system can give you:

• more control over how you light individual areas
• less maintenance
• lower running costs
• improved light quality

Install LED lighting

LED lighting can deliver strong energy and maintenance savings when specified well. Look for products that suit the space, work with your controls, and manage glare.

For larger upgrades, ask suppliers for a simple comparison that covers upfront cost, expected life, energy use, light quality and warranties.

Select energy-efficient alternatives

You can often replace older tubes and lamps with slimmer or more efficient alternatives, or with LED upgrades - see lighting system design.

Upgrade luminaires

As part of installing more energy-efficient lamps, consider upgrading luminaires to more efficient fittings. These can increase the light provided without using more electricity - for example by using mirrors to reflect light into an area.

Upgrade equipment and systems

When you upgrade your lighting equipment and systems there are several actions you can take so that your lighting systems are better matched to:

• the layout of your premises
• the building's occupancy patterns
• the tasks you undertake

These include introducing zoning lighting and controls like sensors and timers.

Building regulation requirements

Building regulations require a certain number of energy efficient lights to be fitted. This applies to:

• new dwellings
• extensions or material changes to existing dwellings
• rewiring of existing lighting systems

An energy efficient light fitting must consist of:

• the lamp
• control gear
• appropriate housing, reflector, shade or diffuser

Tubular fluorescent and compact fluorescent lighting fittings meet this requirement. Tungsten filament and tungsten halogen lamps do not.

Inefficient lighting around your business premises can place a burden on your bottom line. Following the six steps below will help you to improve the way your lighting system operates and reduce your energy costs.

1. Understand your lighting energy use

Go round all your lighting equipment, making a note of where it's installed and how it's used. Ask staff to let you know about any lighting problems and take action. Check that lamps, fittings and controllers are in good working order. Monitor your use of lighting for a period - you can use this for comparison purposes once you have made energy efficiency improvements.

2. Identify your saving opportunities

Make an energy checklist of your lighting. Walk round your building at different times of day to see where you could make savings. The Carbon Trust has produced guidance for businesses on implementing an effective energy management strategy. This includes a sample checklist that you could use as a template for your own document.

3. Prioritise your improvement actions

Draw up an action plan setting out what improvements need to be made, who will make them and when they will be done. Include short-term measures - like writing an energy usage policy as well as long-term plans like a major lighting upgrade.

4. Seek specialist lighting help

You may be able to put in place some energy saving measures yourself, but for others you'll probably need specialist help. Discuss complex and expensive options with a qualified technician. Check to see whether your organisation qualifies for tailored consultancy from the Carbon Trust.

5. Make changes and measure savings

Put in place all your energy saving measures and compare your performance against your original energy consumption figures. Use the information to help decide where more energy savings could be achieved.

6. Review your lighting energy efficiency

Make sure that you maintain your energy savings in the future by regularly monitoring consumption and making sure that your energy policies and procedures are followed.