There was a time when colour temperature and colour rendering didn’t matter so much at train stations. Functionality was king, and it was measured in lux or lumens per watt.
But that time has come to an end, according to rail lighting experts. With the growing trend of train stations becoming shopping malls with platforms, LEDs are going to have to step up and give us better colour performance.
Speaking at the Rail Lighting conference last month, David Burton, an independent rail engineering consultant, said: ‘Mainstream LEDs are only just giving us the colour performance that metal halide gave us 25 years ago. If you want to do something more adventurous, such as advanced retail applications in rail environments, then you do need better colour performance.’
Burton said that while we’ve got used to LEDs giving a ‘decent light output and relatively good power consumption,’ what we haven’t really focused on is colour performance and colour temperature.
‘Thirty years ago, if you walked into a wholesaler to buy some standard fluorescent lamps, you’d probably be able to get them in six or seven different colour temperatures. You can’t do that with LED without going to a specialist vendor and losing quite a lot of efficacy.’
London Underground is already starting to take colour temperature into account. It has recently put together a station design guide, including advice on lighting, developed with the help of top designer Paul Nulty.
Ivan Perre, electrical engineer for London Underground, said: ‘Before, we just wanted to get people in and out safely. Now there are opportunities for retail and cafes and social places – spaces that are comfortable to be in. This all ties in with things like colour temperature, it’s a massive change. Engineers naturally just want to put some batons in and go home, but this challenges the way we think, for the better.’
Lee McCarthy, technical director of lighting manufacturer Designplan, said: ‘The trend has challenged us as manufacturers. A few years ago, if you asked for better colour temperatures and increased CRI people would say “we don’t need that, it’s a station”.’
Burton said: ‘There is so much that can be done with LED and we’ve really got to take much better advantage of luminous science so we can enjoy products which are more aesthetically pleasing and yet still very efficient in terms of performance.’