The lighting industry is on the march, advancing at a rate seldom seen outside the IT industry. This new dawn is quite remarkable when you consider the industry has seen relatively little change for almost a century. What would appear to be the visual embodiment of energy wasting is seeing huge innovation, largely driven by government policy. According to Wired Magazine, ‘it’s making lighting sexy’, something it hasn’t been since the days of Swann and Edison.

The future of lighting is really about the future of sustainable lighting design, as most technical innovation is driven (via government policy, lobbying and, hopefully, some common sense) by the desire to reduce energy use, embodied energy and environmental impact.

The most obvious place to start when discussing technological innovation is the LED. First used commercially in the Seventies as a means of backlighting alarm clocks and calculators, the LED has come a long way in a short space of time.

Only 10 years ago the low output of LEDs made it a relatively poor light source, the brightest being used in low-power marker lights – more often than not these were blue (most efficient) and almost never white (at the time with very poor efficacy). Fast-forward 10 years and the LED is fast becoming a cornerstone of any lighting installation.

We are now in an era where the light output is becoming genuinely useful and the quality of light is starting to approximate that of incandescent light sources. This wouldn’t come as any surprise to Dr Roland Haitz who, back in 2000, postulated the increase in LED efficacy by a factor of 2 every three years. The Haitz law (think Moore’s Law for LEDs) predicted the 100 lm/W benchmark would be broken in 2010; he was pretty much right, although such products are not quite commercially available just yet.

If you follow Haitz’s law to its conclusion it essentially expires in 2020, at which point the LED lumen package will have become so bright that the sources would be too bright for use.

This rate of development has not been all plain sailing. With little standardisation across the industry, each manufacturer is developing and innovating in different ways. While not wanting to suggest stifling innovation it is somewhat worrying, for example, when, for example, you consider an installation that was installed three years ago. By the time it is relamped in three(ish) years’ time the same output LEDs won’t be available. The scheme that was previously designed to 400 lux may suddenly become 1000 lux – far too bright. This is a legacy that designers must consider and design into the scheme from day one.

Another key factor that needs consideration is maintenance. Although LEDs offer extremely long life – white LEDs are around 35,000 hours, though not 50,0000 as many will tell you they have – they are not maintenance free, as inevitably components will fail and most installations will have a longer design life than 10 years, roughly 5,000 hours in use.

Maintenance is an even larger issue than it first appears, as many LED luminaires are either sealed, require an electronics engineering degree to swap the circuit boards or do not have adequate heat sinks for newer LED circuit boards. This usually means throwing the whole luminaire away when maintaining, which, frankly, is appalling as far as environmental friendliness goes.

What is really shaking the LED market right now is the introduction of good-quality retrofit LED products. By dint of being a replacement for incandescent sources, they have some form of standardisation – already adopted sockets (bases) such as GU10, and benchmark lumen outputs (same output as the lamp it’s replacing). These are (relatively) simple lamps that can be easily swapped out and do not require replacement of the whole luminaire.

It’s interesting to see how demand in the domestic market is driving the development of such technologies and how this is in turn is affecting the wider commercial markets; it’s usually the exact opposite, with high-end technology filtering down.

This gets even more exciting when you consider that the likes of Samsung, Toshiba and Sharp are coming to market with domestic-orientated LED products. It inevitably means greater competition, which in turn should drive down prices.

Price, as well as size and light output, is still a big obstacle for the LED’s cousin, the OLED. Whereas LEDs are manufactured by cutting each diode from a wafer of crystals (such as gallium arsenide) layered over a base of silicon or sapphire, organic LEDs use organic molecules laid down on to a thin film.

This technology has several exciting properties. First, the thin film is flexible, which means it could easily be incorporated into clothing or wallpaper or used as a newspaper. Secondly, because it’s an organic compound ‘printed’ on to the film there is every possibility of being able to, quite literally, print your own light source in an identical way to printing out a letter on a desktop printer. You would no longer need a source inside a diffuser as the diffuser itself would emit light.

LEDs and now OLEDS are opening up new ways of integrating lighting into the fabric of a building. From simple details such as uplights as shallow as a carpet tile, or the ability to integrate lighting into a ballustrade, or incorporating lighting into a glass roof, to windows or wallpaper emitting light, there are completely new opportunities to use lighting and affect the spaces around us.

While the general impression is that LEDs have already trounced all traditional sources, this is still far from the truth. ‘Although LEDs occupy 95 per cent of the column inches on lighting these days they actually represent only five per cent of total turnover in lamp products,’ according to Ian Major, product and marketing manager at Havells-Sylvania.

And there continues to be advancements in conventional lamps. Ceravision, for example, has been developing a high-output plasma lamp which is extremely efficient and longlife. Fluorescent lamps have evolved to become as long-life as LEDs, and even the incandescent lamp is now available with a life of up to 10,000 hours – not that it will be around for much longer…

The ban on the incandescent bulb is generally seen in the lighting industry as a sad passing. Its quality of light is as yet unsurpassed and, from a manufacturing perspective, with so few components, reasonably environmentally friendly (unlike fluorescents and LEDs). However the ban is for the good as it has bought into sharp focus the requirement to think sustainably.

Of course, sustainable design embodies more than just low-energy luminaires. It is about ensuring luminaires are environmentally diligent, manufactured in the most environmentally friendly way possible (with few polluting components and minimal shipping), and disposed of with care or recycled.

Cradle to Cradle and Energy Star in the USA are doing just this and for the first time there is the opportunity for transparency in terms of the embodied energy and environmental impact of every luminaire on your project.

It is an additional efficiency benefit of control systems – aside from the more obvious facilities of dimming, daylight linking and absence/presence detection – that we can now also use them to monitor how the product performs during its lifetime .

Further, future developments would appear to indicate the use of RF (radio frequency) detectors. A detector placed on a person would allow the controls system to recall a personal light setting, to know the location of a person within a room, and to provide personalised information on the front-end control panel, such as weather, news and so on.

A reflection of the current and future developments in technology, together with the emphasis on sustainability, is that lighting has never before had such high billing on projects and that the lighting designer has become an integral part of the design team. No longer is it acceptable to simply understand Le Corbusier’s ‘play of light’, we also need to understand how buildings are constructed so that we can integrate our designs with them and consider how our designs impacts upon the environment.

There is also a whole raft of legislation to keep on top of and, really interestingly, there are huge developments in understanding of physiological, sociological and psychological impact of lighting.

And there are some even more exciting developments ahead. Philips, for example, is currently researching the potential of bioluminescence. Imagine no longer needing streetlights – instead the trees lining the road would emit a completely ‘natural’ and ‘free’ form of illumination.

Louvre Pyramid
Schemes such as the relighting of the Louvre Pyramid and the three pyramidions, part of an overall project to relight the entire exterior of the Paris museum, demonstrate not only the drive to use LEDs to save energy, but also the changing face of the lighting industry

Manchester United
Visitors completing a tour of Manchester United exit through this link corridor into the retail outlet. The lighting, by Paul Nulty Lighting Design, features LED strips (supplied by Innovation Signs), a relatively recent LED application that is used widely because of its ease of installation

Nandos
Light Corporation’s custom downlights at Nandos, Westfield, Stratford City uses Xicato’s remote phosphor modules, which have brought LEDs closer to the halogen grail in terms of colour rendering

DW Fitness
RG170 gimbal fittings by High Technology Lighting at DW Fitness, Ipswich, also uses Xicato’s remote phosphor modules, which are improving LEDs’ colour rendering