The advent of LED lighting has created a superb opportunity for energy efficiency, but it’s a mistake to think that making the change to LED is easy. LED lighting comes with plenty of foibles and, unless you know what it can and can’t do (the “do’s and don’ts”) as well as how to use this new directional light source (the “design”) only a percentage of the potential savings will be realised. In some projects, where the design is particularly poor, it may it may even lead to a cost increase!
We all know there’s no substitute for daylight, just how it makes us feel, and as such should always be maximized where possible. The challenge is that in areas that need artificial light a good design can at times seem a fine balance between people’s needs & feelings of wellbeing with energy efficiency.
User considerations such as light levels, glare, light uniformity and comfort are not only a “good thing” but are also regulated by health and safety regulations. Good design is not about making areas look pretty, but how they should be used. The approach should be collaborative; designers should talk to the occupants and understand how they use the space, what needs to be lit and by how much. In many cases increases to worker health and productivity will more than offset small increases in energy usage so long as the lighting is for a specific purpose.
To maximize energy reduction benefit lighting controls such as occupancy sensors, dimming as well as building automation are ideal but selecting the correct control is important; use of microwave presence sensors in restrooms may be fine as they will also detect presence in cubicles, but may not work in corridors where movement in neighbouring rooms cause a false trigger. Designed correctly, an integrated system with controls may cost 10% more but will typically realise additional savings of 20% or more.
In our experience there are a lot of myths around energy efficient lighting upgrades, and below we debunk 10 of those we consider the biggest:
| Myth | Reality | |
| 1 | For most businesses, better lighting is a simple case of creating more light | Most added light is wasted and causes glare and contrast issues |
| 2 | Incandescent lamps are better than CFLs as they don’t contain mercury | In fact, pollutants emitted by incandescent lamps due to higher heat & energy use are 10x higher than the mercury contained within CFLs |
| 3 | Saving lighting energy isn’t as beneficial as saving HVAC energy | Lighting constitutes, on average, 22% of a commercial properties energy consumption.For every 1000W of lighting reduction this leads to a 2-300W of reduced HVAC load. |
| 4 | LEDs last up to 5 x longer than fluorescents | Certainly true for older T10 lamps, but modern T5 lamps can have a life of 50-60,000 hours.The electronics inside LEDS are sensitive and can fail early if poorly implemented. |
| 5 | LED lamps don’t create heat | They do, just less! Care still needs to be taken with airflow and heat escape or lamp life is reduced. |
| 6 | Using lighting sensor controls offers better return on investment than changing the lamps to LED | Sensor offer fantastic savings but work best with LED as they are “instant on full” and are not affected by turning on and off “switch cycles”. |
| 7 | Constantly turning lights on and off reduces lamp life | In older lamps, after 5 minutes the loss of life is overcome by operational savings. A quality LED lamp’s life isn’t affected by switch cycles. |
| 8 | Updating our lighting to LED will lead to decreased energy cost, less maintenance and save money | Poor quality LED lamps can lead to an increase! Lamp “power factor” should be at least 0.85, and have a warranty of at least 30,000 hours. |
| 9 | Adopting LED is easy, we just need to change the lamps | LED are far more complex than older types of lighting, especially with dimmable lighting or where large numbers of lamps are on a circuit. Never be tempted to mix different types of lighting or even models on the same switch circuit. |
| 10 | Lighting doesn’t need to be designed | It is proven time and again that technology can offer 40-60% of the possible savings but proper design to decrease the load will release the rest!Lighting should be fit for purpose; task lighting, accent or detail as well as general background light. |