A flexible friend
As lighting control technologies continue to develop there is considerably more scope to address each user’s requirements as well as environmental and sustainability issues.
Controls for building services in general, and lighting in particular, have received a real boost in recent years, thanks to the recognition that no matter how well designed a piece of kit is, it will only be as efficient as the way it is controlled.
Regulations such as Part L of the Building Regulations and tools such as BREEAM and LEED focus attention on energy efficiency and sustainable design, while other drivers including the Carbon Reduction Commitment encourage major energy users to seek ways to remain below set energy consumption thresholds.
Not surprisingly, the majority of new build and major refurbishment projects now include some level of lighting control while organisations seeking to reduce overheads and energy consumption are retrofitting controls to existing installations. The result is that, in general, lighting is being controlled more effectively in many more buildings. However, there is still a long way to go, and the latest lighting management systems offer much more in terms of efficiency and sustainability.
Lighting management systems enhance energy efficiency through presence detection, absence detection and daylight-linking, yet savings can be greatly increased through integrated control of other energy-consuming devices such as HVAC. Lighting management sensors can relate heating/cooling temperature bands to occupancy so that unoccupied areas operate under a wider band conserving 4% energy for every temperature degree saved. High-speed, open protocol technologies, such as Lon or IP, not only achieve savings through integration, but also cost and material savings through shared network cabling and infrastructure.
Dimming enables savings to be achieved efficiently yet subtly through daylight-harvesting and the ability to optimise lighting levels to maximise energy efficiency: however there is more that can be done here too. For instance, most DALI systems will still use residual power when on standby – so selecting a latest zero-power DALI system will give even greater energy savings.
Of course, being green and environmentally friendly is not only about energy efficiency but also about the life cycle carbon equation and total lifetime environmental impact of a project.
One aspect of improved control is that the running hours of lamps are reduced, so that lamps last longer and need less frequent replacement. However these benefits are not realised if lamps are changed in bulk on the basis of average lamp life. So it’s worth considering the introduction of hour-run measurement, which identifies the optimum time for individual lamp replacement. This approach reduces maintenance costs, as well as the financial and environmental costs of lamp disposal.
Another consideration is that of embodied energy. One issue that relates to many speculative developments, especially in the current climate, is that the developer will want to keep the initial capital outlay as low as possible, often opting for controls that meet the minimum requirements of the Building Regulations. Unfortunately, this arrangement may not meet the requirements of incoming tenants, who may discard the shell and core controls and replace them with a more functional system. Clearly, this represents significant wastage of raw materials, all of which have embedded carbon, quite apart from the cost implications.
So what is needed is a flexible design approach that helps developers let their space and enables building occupiers to quickly and easily fine-tune their lighting to changing circumstances. The ideal situation is a modular and scalable system that meets the requirements of Building Regulations as standard but also has the inherent flexibility to be quickly, easily and cost-effectively upgraded to a more powerful system should the need or desire arise.
The key factor is that specifiers are aware of the possibilities and take advantage of the opportunity to build in the maximum amount of flexibility from the beginning of the project. Such an approach will ensure that not only are the control systems designed for the near future but will also be able to continue to address the occupier’s needs through the life of the building.