All aboard, tickets please roll up, roll up, roll up! I’m off on the next lighting bandwagon, LED lighting.
I remember the last great lighting bandwagon, hydrogen dichoric, generated out of the 1980s. These little display type lamps are now resident in the world’s housing in plague proportions. Installed by a self-congratulating horde of manufacturer’s agents, under the mighty banner of green, energy efficient and reduced lighting load. Not just in houses, but spread all across the interior lighting scenarios of the 1980’s, supermarkets, luxury hotels, yachts, and even in offices, receptions and toilets.
I still fondly recall the jingle boom sounds of the ‘snake oil caravan’ at the end of the street corner. I stand guilty as charged amongst them now. Yes, I sold halogen as the ultimate new technology capable of improving the bottom line, and restoring the green balance. There was little real energy saving available by using halogen-lamps, they were only about 15 to 20 per cent better than incandescent lamps. The only real efficiency was in applying lighting in a focused way, like in retail merchandising. The product became a fashion, and soon the lighting industry was applying this misunderstood technology to all or every type of application.
So fast forward 20 years or so and see that glow on the horizon now. Not the early morning sun catching the Sultans Tower in a noose of light (apologies to Omar Khayyam). No, it is the glow of the tidal flow of new LEDs for the lighting industry.
Yet another bandwagon, and this one is no different.
LEDs are becoming fashionable. Drop them into conversation. Just mentioning them at design meetings will earn you points. As with all fashions, the heat is on to use LEDs. The snake oil salesmen are doing their work well. Nearly everyone is convinced, except of course the skeptical lighting designers. The real difference this time around is we can take better care at the design end of things. Are we not wiser since the halogen fiasco of the 1980s? Houses were burnt down from poor installations, shops’ air conditioners overheated from the many transformers located in tiny cupboards, and people were personally injured by the glare and heat.
In a growing movement of common sense proportions, educated lighting designers are beginning to understand the truths behind the technology, and to set upon the task of establishing rules of play. The bright way forward! There will always be, and have always been, ‘snake oil’ sales people who can sell ice to Eskimos.
But this new fashion craze for LEDs must be tempered with common sense engineering attitudes.
Dangers of choice
The big problem with this new light source is that anybody can peel the label off a soup can, drill a hole in it, and stick a glowing LED in place, and claim to have a light fitting. So many new LED products arrive on the market looking very like a neat and tricky new ‘throw away toy’. Marvelous industrial design and beautiful aesthetics – while incredible claims about LED life, lumen output and performance are made. However, upon the extinguishment of the LED source the whole product is thrown to land fill. Even if it has some recyclable components, the intrinsic or embodied energy in the product is discarded.
The reality of modern design thinking must always involve a very practical use of any lighting technology. Rather than a throw away economy, lighting designers are thinking about replacement and re-use of all hardware. Very clever manufacturers are providing products with replaceable LED segments so the light source can be changed. The housing might stay in place for the lifespan of the retail shop, or for the life of the hotel fit out, or in the case of tunnel lighting, stay in place in the ceiling mounted lighting array for many years, even decades while the LED sets are replaced upon failure, and the control gear upgraded when it too fails.
This is the key point. The hard-won extracted metallic resources used in making the housing and reflectors are used and re-used, and cleaned perhaps and reused again.
Laying down the law
This is sustainable thinking. This is green, and is very definitely ‘low carbon’.
It is not about the snake oil man selling his miracle cure of LED potions and spinning almost unbelievable claims about performance efficiency and so on. It is about careful choices of technology:
– Replaceable LED sets (pucks, racks or arrays) – changing the light source, not the light fitting
– Maintainable housings – designed to a quality that lasts many LED set changes
– Temperature test data – relates to continuing performance of the LEDs
– LEDs operated at median milliamp settings to lengthen life – not overrun to squeeze out high performance statistics at the expense of lifespan
– Sophisticated control gear that monitors temperatures, and adjusts the LED voltage accordingly
– Careful selection of control gear and switching, matched to LED and printed circuit board to ensure continuing performance
– Choice of LED chips from high quality established manufacturers (that will be here in 20 years)
– Suppliers that ‘BIN’ test their LEDs, and document the output to clients for future re-lamping quality
– Certified photometric reports, providing absolute photometry based upon a particular type of equipment
– New improved LED sets that can be fitted to older existing housings.
Final thoughts
All of this applies to LED technology in tunnels. The biggest challenge in tunnels outside Europe in the warmer climates is the high temperatures prevalent in the ceiling/roof spaces. LEDs are highly temperature sensitive. This factor alone may prohibit LED technology from such places as Australia, Africa, and other subtropical regions.
The use of LEDs is successfully achieved in cooler and darker climates such as in Holland. Nevertheless, the rules of play outlined above must be enforced by lighting designers.
Lighting designers – call to arms! Follow these rules and impose them on your suppliers.
It will be a better world as a result. And we can all be part of a successful and sustainable product roll out.
