Lighting

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Lighting can consume up to 40% of energy in commercial premises, depending on the nature of the business and type of lighting used.

The biggest impacts on electric lighting requirements and design come from the architectural orientation, massing, ceiling height, and section profiles that determine daylight availability in a building.

Lighting designers should be involved early in the design process of new buildings or retrofits. A good energy-efficient lighting strategy relies on an integrated approach.

Existing lighting systems

Many lighting efficiency opportunities can be easily implemented with little or no capital investment or any need to redesign a lighting system. These include turning lights off manually or automatically when not needed, or removing excess lamps from over-lit areas.

There are excellent opportunities for energy saving whenever upgrades or refurbishments are planned. Options for upgrading energy-efficient lighting can be applied to all types of commercial, industrial and service facilities, and may include replacing light fittings and lamps, optimising lighting layout, and adding more circuits and switches for greater control and automation.

LEDs

Old-style incandescent (including halogen) bulbs are highly inefficient, burning most of the energy they use as wasted heat. This also makes them a fire risk.

Light emitting diodes (LEDs) use up to 75% less energy and emit 90% less CO2 than the old halogens. They also last up to 25 times as long which greatly reduces the need for changing or maintenance. This is especially useful where fittings are difficult to access.

LEDs generate less heat than halogens meaning the load on air conditioning is reduced. They also emit 50% less CO2 than compact fluorescent lights (CFLs) and, unlike CFLs, don't contain toxic mercury.

Quality of LEDs can vary, so look for reputable name-brand products.

Daylighting

Good lighting design includes consideration of daylighting, the admission of natural light.

Window design must strike a balance between the admission of daylight and not allowing harsh, direct sunlight into the eyes of workers or reflected glare from surfaces.

Heat levels from direct sun also need to be controlled. Curtains and shades should always be used in conjunction with daylighting strategies.

A daylight-optimised building footprint is essential for new building designs. For many buildings, there are several effective measures to maximise natural lighting indoors:

daylight-optimised interior design, incorporating furniture, space planning, surface colour and texture
skylights
daylight redirection devices
daylight-responsive electric lighting control
high-performance glazing.

Innovations are bringing down the costs of high-tech windows, such as low emissivity (‘low-e’) glass opening up daylighting options while minimising glare and heat gain in commercial buildings.

Lighting controls and sensors

Occupancy/motion sensors

An occupancy sensor (a type of motion sensor) detects when a room or area is occupied and when it becomes vacant. Lighting is adjusted accordingly. This offers hands-free convenience and substantial energy savings. Occupancy sensors are ideal for meeting rooms, storage and print rooms, and bathroom facilities.

Outdoor motion activated lights illuminate an area when people approach or enter it, such as a carpark or building entrances. Along with the energy benefits, motion-activated lights provide convenience, safety and added security.

Timer controls

Timer controls do not respond to changes in occupancy but are instead pre-set based on the expected use of rooms. This is useful when room occupancy times are consistent and predictable.

Lighting timers can be manually operated or automated. Manual timers are plug-in units that are adjusted to set lighting times. Automated timers are generally in-wall programmable digital units that can be integrated with a building management system (BMS).

Innovations

Electrodeless induction lamp and LEDs

The induction lamp’s main advantages are long life, ease of replacement and low maintenance. These lamps have mostly been applied where high lamp replacement is difficult and expensive.

The efficiency of induction lamps range from about 56lm/W to 80lm/W. This is less impressive than some LEDs (90lm/W or more) which are also claiming equivalent lamp life and lower long-term capital costs. As LEDs further improve in power output and live up to the predictions of lamp life, they can be expected to compete increasingly successfully with induction lamps.

Simulations and new building materials

Computer simulation helps designers provide daylighting without needing direct sunlight. New glazing materials admit light while blocking infrared and ultraviolet light. Double-glazed windows admit light while halving heat conduction, and various low emissivity coated glass can also help to manage radiant heat gain.

Other innovations include light pipes, panels that reflect light onto ceilings, and aerogel panels that insulate whilst letting in daylight.

Smart pole street lighting

LED smart poles are already in use in many cities around the world. The poles are operated via a centralised online hub to remotely control and monitor street lighting and other services. Automated sensors detect ambient local conditions, such as visibility, traffic and weather. The poles integrate with the Internet of Things (IoT) cyberscape.

Smart light poles are ideal for installation at university campuses, housing complexes and industrial estates.

See the Lighting Manufacturer website for more information on smart light poles.

Daylight response

Daylight response or ‘harvesting’ technology uses photosensors to instantly adjust output in response to available ambient light. This technology is available as an integrated feature in common LED fittings, including for factory high bay lamp types. Daylight response ensures productive levels are maintained perfectly and energy costs are minimised.

State and territory programs

Subsidised programs are available in some states and territories for LED lighting upgrades.

The NSW Government’s Energy Savings Scheme offers subsidies for eligible small businesses. Approved suppliers work with business to determine how much energy could be saved with and energy efficiency upgrade.

The Government of South Australia‘s Retailer Energy Productivity Scheme (REPS) provides subsidies to eligible businesses to upgrade their entire premises to LEDs.

The ACT Government has support available for ACT businesses interested in lighting upgrades. This includes a Lighting Efficiency webtool that checks the efficiency of your business lighting setup and suggests possible upgrades.