cpd 6 2014_ sustainable lighting _ features _ building design

7/27/2019 CPD 6 2014_ Sustainable Lighting _ Features _ Building Design

1/6

CPD 6 2014: Sustainable lighting28 February 2014

Improvements in LED technology offer architects more ways to integrate light into theirdesigns. As lighting is one of the most energy-intensive elements of a building, such optionsare vital

How to take this module

To take this module read the technical article below and click through to a multiple-

choice questionnaire, once taken you will receive your results and if you successfully passyou will be issued automatically with a certificate to print for your records.

Architects in the UK have traditionally not
http://www.bdonline.co.uk/http://www.bdonline.co.uk/attachments.aspx?js=yes&height=auto&width=820&storycode=5066837&attype=P&atcode=1783348http://www.bdonline.co.uk/attachments.aspx?js=yes&height=auto&width=820&storycode=5066837&attype=P&atcode=1783347http://www.bdonline.co.uk/attachments.aspx?js=yes&height=auto&width=820&storycode=5066837&attype=P&atcode=1783350http://www.bdonline.co.uk/


2/6

specified lighting, because it has beenconsidered part of the fit-out and has thereforeonly been considered at a later stage. However,

this is changing quickly with the advent of light emitting diodes (LEDs), and architects arestarting to integrate lighting into their designs by engaging specialist lighting designers.New forms of luminaire may also be used to illuminate existing structures.

It is increasingly important that lighting is not treated as an afterthought. The need to designbuildings that perform well against environmental ratings systems such as BREEAM hasplaced greater emphasis on the operational performance of building systems. As lighting isone of the most energy-intensive of those systems, accounting for up to 40% of energy usein non-residential buildings, architects are advised to make lighting specification an integralpart of the design process.

Focusing on lighting design is not just a question of sustainability. The need for energy-efficient illumination has led to the dramatic rise of LED technology, and this, in turn, hasopened up new possibilities for lighting design. While technology plays a vital role inreducing energy consumption, the design of installations can be equally influential inachieving these goals.

This CPD will consider the key considerations for lighting design in energy-efficientbuildings and the opportunities that LEDs can offer designers.

Types of light source

There are three main traditional sources of electric light filament, discharge andfluorescent. Their key characteristics are outlined in this section, alongside those of morerecent LED technology.

The comparative effectiveness and efficiency of these light sources can be assessed in termsof five key criteria:

Colour temperature This is measured in kelvin (K). Temperatures of more than5,000K are cool colours (such as bluish white), while lower temperatures (2,700-3,000K) are warm colours (yellowish white to orange)Colour render ing index (Ra)This is a measure, on a scale of one to 100, of howfaithfully a light source renders the colours of objects in comparison with a naturalsource 100 on the scale equates to sunlight.EfficiencyThis is expressed in terms of the lumens of light produced for every watt ofenergy consumed (lm/W)Design life The approximate number of hours of operationDimmingThis is best expre-ssed as a yes or no answer, but there may be exceptions.

Filament

The filament lamp is an incandescent light source, and its main advantage is an excellent Raof 100. Tungsten filament is the chosen option for most museums and galleries around theworld, as it allows artefacts to be displayed in a setting akin to natural light. At just 12-14lm/W, it is an inefficient source, and it has a rated life of just 1,000-2,000 hours.

Discharge

The first gas discharge lamps were sodium street lamps, developed in the 1930s. Low-pressure sodium lighting is still an efficient option, but gives poor colour rendering. Othergas discharge options, such as metal halide lamps, have been developed to provide better

colour rendering, white light and long life. Ceramic metal halide, for example, has an Ra of85, which is perfectly acceptable for a retail environment, and 90% of high street shops useit for their accent lighting. At 90lm/W, these lamps are eight times more efficient than astandard tungsten lamp and have a durability of 14,000 hours almost four years in a retailenvironment.


3/6

Fluorescent

The traditional fluorescent lamp achieves good colour rendering and can exceed 100lm/Wfor efficiency in some lamp types. With up to 20,000 hours of life, it is the lamp of choice inschools and offices, where uniform lighting is paramount. As a light source, it is inexpensive.

LED

LED technology is developing at a rapid rate. The main technological innovation over recent

years has been the development of warm colour temperature white light, which can closelymimic tungsten halogen light sources. It is clear that, due to ever-stricter energyregulations, the efficiency and long life of LEDs will eventually render the other light sourcesobsolete.

Specifying the correct luminaire

Many specifiers believe that all luminaires perform equally well. In reality, factors such asreflector design, the focal point of the lamp and the quality of the materials used will lead tosignificant differences. The main performance aspect to consider in a luminaire is its lightoutput ratio (LOR). If the luminaire has an LOR of 0.6, it means that 60% of the light producedis being used to illuminate the required space. The rest is essentially being wasted.

For example, in the case of a low-quality acrylic downlight, it is likely that a large

percentage of the light would be lost or absorbed, giving an LOR of potentially only 0.4.Therefore, a greater number of fittings would be required to achieve the same light level asa 0.8 LOR downlight, resulting in higher energy consumption. The importance of the LOR isshown in the following light illuminance calculation for a 5m x 5m room lit with 12downlights using 2 x 26W compact fluorescent bulbs:

Using a very efficient luminaire with an LOR of 0.74, an average illumination level of774 lux can be achievedUsing a luminaire with an LOR of 0.39, the average illumination level falls to 484 luxThe use of the more efficient product therefore leads to a 60% increase in illuminance.

dditional benefits of LEDsAs mentioned already, the efficiency and durability of LEDs are likely to make all other lightsources obsolete. Architects should, therefore, be aware of the challenges and opportunitiesthat designing for LEDs presents.


4/6

Architectural lighting

LEDs bring a number of advantages to the night-time illumination of landmark buildings andmonuments. They use about 40% less energy than traditional fluorescent and metal halidesolutions, are not sensitive to low temperatures, and require very little maintenance. Red,green, blue (RGB) luminaires are also a very effective way to create efficient colour effects.This is because an RGB generated at source is significantly more efficient than using a colourfilter.

Efficiency through optical design

A fluorescent tube emits light across its surface and the amount of lighting provided is oftenmore than required. With LEDs, the light source is a much smaller point, so better opticalcontrol is achieved. This is not only more efficient but offers greater precision for lightingdesign.

New forms of luminaire

The comparatively small size of LEDs has allowed manufacturers to introduce compactluminaires. With these, architects and lighting designers are able to illuminate a project

without the luminaires themselves creating an unwelcome visual impact on the ceiling andwalls. By considering such luminaires earlier in the design process, architects can completelyintegrate lighting into the structure.

Street and urban lighting

For street and urban lighting the switch to LEDs has meant a major rethink in lightingdesign, energy management and maintenance regimes. This has led to lower lifetime costs,reduced traffic congestion (because there is less need for disruptive maintenance) andreduced light pollution. It has also allowed for better lighting control, the ability to dimlighting without colour shift, and a move away from coloured street lighting. Many publicauthorities are now making the switch to LED for streets and urban areas.


5/6

Postscript:

0 Follow @bdonline 31.6K follow ers

Novamed Hospital, Zagreb, by architect Studio Ante Murales and lightingdesigners Dean Skira and Maja Lipovcic.

Lighting control systems

Once a light source and luminaire type has been chosen, specifiers must also considerlighting control systems, which are becoming an increasingly important aspect of energy-efficient design, particularly on large projects.

The main elements of a lighting control system are presence detectors, scene setting,daylight linking, timed programmes, maintenance and failure detection, and the means ofintegration with other systems such as air conditioning and blind controls.

International lighting protocols such as DALI or DMX ensure that luminaires and controlsystems are always compatible, regardless of supplier. If all of the above factors areincorporated, lighting control systems can achieve significant energy savings

This module is sponsored by iGuzzini. For more information

[email protected] @iGuzziniUKPinterest.com/iGuzzini

BDs free continuing professional development distance learning programme is open toeveryone who wants to develop and improve their professional knowledge. Thesemodules can contribute to your annual CPD ctivity and help you maintain membership ofprofessional institutions and bodies.

This module will contribute 1 hour towards your CPD obligations. If successfullycompleted, certificates will be distributed two weeks after the module closes.

Duration: 1 hour

Module 6 Deadline : 11 April 2014

Privacy policyInformation you supply to UBM Information Ltd may be used forpublication and also to provide you with information about our productsor services in the form of direct marketing by email, telephone, fax orpost. Information may also be made available to third parties. UBMInformation Ltd may send updates about BD CPD and other relevantUBM products and services. By providing your email address youconsent to being contacted by email by UBM Information Ltd or otherthird parties. If at any time you no longer wish to receive anything fromUBM Information Ltd or to have your data made available to third

parties, please write to the Data Protection Coordinator, UBM Information Ltd, FREEPOST LON15637, Tonbridge, TN9 1BR, Freephone 0800 279 0357 or email [email protected].

0Like

e
http://www.addthis.com/bookmark.php?v=300&winname=addthis&pub=ubmbebd&source=tbx32-300&lng=en-US&s=linkedin&url=http%3A%2F%2Fwww.bdonline.co.uk%2Fcpd-6-2014-sustainable-lighting%2F5066837.article&title=CPD%206%202014%3A%20Sustainable%20lighting%20%7C%20Features%20%7C%20Building%20Design&ate=AT-ubmbebd/-/-/531bcbd5a247f90c/4&frommenu=1&uid=531bcbd55d9159dd&ct=1&tt=0&captcha_provider=nucaptchahttp://www.bdonline.co.uk/business/cpd/cpd-6-2014-sustainable-lighting/Pinterest.com/iGuzzinihttp://www.bdonline.co.uk/business/cpd/cpd-6-2014-sustainable-lighting/Twitter%20@iGuzziniUKhttp://www.bdonline.co.uk/business/cpd/cpd-6-2014-sustainable-lighting/www.iGuzzini.co.ukhttps://twitter.com/intent/user?original_referer=http%3A%2F%2Fwww.bdonline.co.uk%2Fbusiness%2Fcpd%2Fcpd-6-2014-sustainable-lighting%2F5066837.article%3Fbid%3D4536695%26cid%3D69325%26seg%3DCell1%26lid%3D66713&region=count_link&screen_name=bdonline&tw_p=followbutton&variant=2.0https://twitter.com/intent/follow?original_referer=http%3A%2F%2Fwww.bdonline.co.uk%2Fbusiness%2Fcpd%2Fcpd-6-2014-sustainable-lighting%2F5066837.article%3Fbid%3D4536695%26cid%3D69325%26seg%3DCell1%26lid%3D66713&region=follow_link&screen_name=bdonline&tw_p=followbutton&variant=2.0


6/6

Related Company Resources

The single resource for all your building design industry needs
http://bdonline.verticalsearchworks.com/EN/Microsites/http://bdonline.verticalsearchworks.com/http://bdonline.verticalsearchworks.com/EN/Microsites/http://bdonline.verticalsearchworks.com/EN/Microsites/

cpd 6 2014_ sustainable lighting _ features _ building design

Documents