Tuesday 26th June 2012
When comparing power consumption of emergency lighting, and more specifically comparing LED lighting with standard lighting, it is important to understand some of the terms used and what they actually mean in this context. Sometimes you will see the power consumption documented in W (Watts) and sometimes it will be stated in VA (VoltAmperes). Whilst this looks confusing, it is comforting that both terms are actually identical. Multiplying the Voltage (V) of the electrical supply with the Amperage (A), which represents the current flowing through the light, gives you VA (VoltAmperes) which represents power consumption and is actually the same as the ‘Wattage’ (W). So VA equals W; they are just different ways of saying the same thing.
For this blog we will be comparing a CS8 maintained emergency bulkhead with an X-GSA LED maintained emergency bulkhead as they are very similar units, although they have a very different power consumption (also the CS8 produces light output of 100 lumens, whilst the X-GSA produces a slightly lower 85 lumens. This difference, though, is negligible.).
The CS8 contains an 8W T5 lamp which, as the name suggests, consumes 8 Watts. The ballast (the electronics that run the unit and the trickle charge for the backup battery) consumes 12 Watts, which means the CS8 in maintained mode consumes 20W.
The X-GSA contains 12 white LEDs which together consume 0.9W. The ballast consumes 2.6W, which means the whole unit in maintained mode consumes 3.5W.
That is a difference of 16.5W, which is huge when you consider that maintained lights are lit constantly. So, a CS8 in its maintained mode is consuming over 5 times more energy every hour than the X-GSA!
It is also important to know that LED emergency lights last substantially longer than fluorescent tubes. An LED bulb will last over 5 times longer than a traditional fluorescent light.
Generally speaking LED emergency lighting is more expensive than the traditional equivalent, but when you factor in the substantially lower power consumption and the lower maintenance needs of LED lights, they are actually more cost effective in the long term.