While there are many strands to carbon footprint reduction, commercial lighting is probably the most visible and emblematic of the struggle.

We all know that changing to low energy light bulbs can reduce energy consumption. But such lighting is still often left on when rooms are empty, dramatically illustrated by any night-time city skyline. Plus there is the residual heat generated which causes extra load on a facility’s air conditioning plant.

Constant Daylight
Simple timers can reduce some of this overhead, as can presence detection (which automatically switches lights on and off when someone enters/leaves a room) or absence detection (which requires manual light activation but automatically switch off when someone leaves.) But now there is a smarter and greener adjunct to these tools: Constant Daylight (also known as Daylight Harvesting.)

The idea behind Constant Daylight/Daylight Harvesting is simple: using a combination of presence/absence detectors, light level detection and intelligent software, a lighting controller adjusts the lighting of a room to complement current natural light, producing a comfortable, constant lighting load which is switched off when occupancy has ceased.

One product that includes Constant Daylight/Daylight Harvesting functions is the DLC1000 Light Control Module from Durable Technologies. This Light Control Module works in conjunction with multiple DLS1000 sensors to constantly monitor for absence and light levels, adjusting lighting for a comfortable working environment, eliminating it when no-one is in the room.

Using less power
So effective is Constant Daylight that in a recent installation, on a typically overcast British spring day, the DLC1000/DLS1000 combination kept the ambient light level in a classroom of 15 sq m at a steady 300 lux and used 60 per cent less power than conventional lighting. And in some cases, a bright, sunny day enables Constant Daylight to eliminate artificial light use altogether. Obviously Constant Daylight cannot be used at night, but presence/absence detection means that full lighting is only used when a room is occupied, changing your building to a low-carbon gap in the night skyline.

Durable Technologies designed the DLC1000 Light Control Module as a KNX device, it is certified to work with any of the thousands of other KNX building controls available from manufacturers world-wide, delivering the cost saving benefits of open standards at a time when budgets are tighter than ever.

That’s why Constant Daylight/Daylight Harvesting is a powerful and cost effective tool in your quest for ever greater carbon footprint reductions.