Perspectives

Regaining Control

Although it has been recognised since the invention of the candle snuffer that lighting systems require control mechanisms to regulate how much lighting is emitted and when, in recent years the installation of lighting controls in building projects has become synonymous with saving energy. Bernard Pratley, Senior Technical Manager with the United Kingdom’s Lighting Industry Association (LIA) believes this focus detracts from their wider benefits.
0 comments
:
 

Historically, the arrival of electric lighting was followed by the introduction of two, distinct types of lighting control system based on different economic models.

Energy saving systems were required to meet a cost that was seen to relate to electricity savings that could be achieved and offered simple switching regimes for little financial outlay.

Whereas scene-setting systems included more sophisticated dimming and programmable controls that were designed to provide users with a sense of comfort and wellbeing (“mood” lighting) and considerable choice over the selection of lighting effects.

Although both streams of the lighting controls market have converged today, the very existence of two, separate markets in the past confirms the advantages of lighting controls must extend beyond merely saving energy.
Intelligent Lighting Controls

The lighting controls industry has long held the view that “intelligence” components in lighting systems will move towards the light source and input devices such as sensors and overrides; in a similar way to that in which computing migrated from large, mainframe machines physically attached to terminals, to desktop, laptop and handheld devices.

Originally developed by energy saving lighting control manufacturers responding to market demand for solutions to the requirements of new types of building (examples in the United Kingdom included the Lloyds Underwriters Building in London which was completed in 1986 and features transparent glass facades and interior partitions), intelligent systems targeted luminaires both individually and simultaneously.

The development of these systems also altered how lighting installations were undertaken. For the introduction of lighting control modules with multiple socket outlets gave birth to the age of plug and socket lighting installations that would group six or eight (and sometimes even more) sockets into a single box but still leave sufficient physical space for a significant amount of additional electronic gadgetry. These new boxes could also be configured to include connection points for local sensors and override switches that required little power and operated at extra-low voltage.


Simpler Installation

Plug and socket lighting installations also move significant amounts of work off-site and into lighting control manufacturers’ factories, resulting in both lower original costs and reduced costs of ownership when compared to conventional, hard-wired systems.

Significantly, the lower cost of original installation also applies to fit-outs and when lighting needs to be re-configured in response to changes to a building’s accommodation layout.


Towards Even Greater Control

Lighting controls continue to offer these benefits and more.

The lighting industry itself has driven evolution by investing in addressable control gear and the digital addressable lighting interface (DALI) and digital multiplex (DMX) control gear, in particular.

Multi-socket lighting control modules (LCMs) no longer need to identify individual loads via a dedicated socket outlet since DALI addressing does this and, as a consequence, lighting control modules are continuing to evolve into devices with fewer sockets that cost less and require less space.

By way of illustration, a typical false-ceiling type installation based on eight socket LCMs will require 40 per cent less cabling than one in which eight luminaires are “daisy chained” from a single output.

Furthermore, increased addressability and functionality within these systems means they perform the scene-setting operations controlled previously by separate systems.
Software Integration

The development of dedicated software for setting-up and running lighting control systems has brought benefits too.

Modern systems incorporate monitoring capabilities that provide energy usage data and even lamp failure reports.


A building-wide lighting control system that is properly fitted out with local sensors and overrides is a powerful source of data on current occupation levels within a building...

 

Emergency Lighting Integration

There has also been progress in another significant area.

Many buildings used to have separate lighting controls and addressable emergency lighting test system. Today, single systems will manage both since the DALI standard includes commands and feedback tailored to the management of the emergency lighting element of an installation.

Researchers in the United Kingdom have calculated the savings that result from being able to test and monitor emergency lighting in buildings automatically equate to more than £30 per lighting fixture annually.


Building Control System Integration

It is said lighting installations are the most pervasive of all fixed building services and this creates an opportunity for control systems to deliver another benefit; especially in large office buildings, educational and healthcare facilities.

A building-wide lighting control system that is properly fitted out with local sensors and overrides is a powerful source of data on current occupation levels within a building and can be integrated, whether locally or through the use of software, with other critical building control systems that manage heating, ventilating and air conditioning (HVAC) and security systems.


What about Energy Savings?

Although we have considered the multiple reasons why building owners should insist on the provision of automatic lighting controls, the ability of these systems to reduce lighting electricity use must not be forgotten.

Matching applied lighting control systems correctly is vital during the commissioning process; especially in office environments, since attempting to “guess” where work desks will be situated will not produce acceptable results.

And ensuring there is always a trained operator who is familiar with the parameters of any system and any operation and maintenance manuals provided by the lighting control systems supplier, is also essential.


Recent developments in lighting energy regulation in the United Kingdom

  • 2013 Amendments to the Building Regulations
  • A recent amendment to Non-Domestic Building Services Compliance Guide
  • The United Kingdom has recently amended its Building Regulations by adding Documents L2A and L2B of the Building Regulations (2013)
  • The 2013 Non-Domestic Building Services Compliance Guide addresses the impact and use of lighting controls.
  • Introduction of a simplified Lighting Energy Numeric Indicator (LENI) as a route to compliance, and greater emphasis on the use of dimming as a control strategy.
  • LENI is derived from standard EN 15193 and is a methodology for calculating the actual use of lighting electricity within a building.

 

Dimming

In the United Kingdom, the use of lighting controls is already built into the National Calculation Method (NCM) that enables designers to determine the Target Emissions Rating (TER) of a notional building. The NCM includes both daylight linked operation and occupancy control, but not controlled (or constant) illuminance. So whether you are going to go for the product efficacy or the LENI route, a dimmable system will deliver additional savings towards the actual Building Emissions Rating (BER).

The 2013 version of Part L now includes Table 42 showing all the new control factors and the impact of using different control strategies in combination with each other. As a result it is possible – with the right choice of controls – to achieve a control factor of 0.70, which effectively reduces the minimum required luminaire lumens per circuit Watt from 60 to 42! The lighting designer is being offered a much wider choice of luminaire design to suit the task, interior and people involved.

 

The Lighting Industry Association (LIA) has both information and training courses available to help you to understand the new provisions of Part L as well as the use and application of lighting control systems. The Lighting & Building Regulations course, Part L, will provide you with an understanding and detailed advice on the Regulations and Approved Documents and the LIA Lighting Controls Design and Application course will explain how the application of a lighting control system can deliver much more than just the important element of energy management. There is a 75 page Lighting Controls Guide, and a Mini Guide to the Provisions of Part L on their website. Find out more at www.thelia.org.uk.

LIA training courses can be delivered at an organisation’s own premises and tailored to suit your needs. Email [email protected] to discuss your requirements.

 

Bernard Pratley

About Bernard Pratley

Bernard Pratley is Senior Technical Manager with the United Kingdom's Lighting Industry Association (LIA) which is the largest organisation representing the interests of the lighting industry in Europe. www.thelia.org.uk

Article Rating

Vote Data