This may sound like one of those silly quiz questions, but it is actually quite a serious one. And the answer can vary tremendously depending on the location of the light bulb.
In a station, where a ladder can safely be used, the answer may be two. If a scaffold tower is required, it may be three – two constructing the scaffolding tower and one on top.
At Westminster Underground station, where rope access is required, it could be more than that – and on highly skilled pay rates as well.
On a platform, lampposts have to be unlocked and rotated to the ground. In car parks, much the same except the lampposts can be much taller, and heavier.
Then there is the train itself. It could have to be returned to a depot overnight rather than merely being stabled somewhere.
If it’s a signal light, a van with two or three people gets sent out and that’s the last anyone will see of them for half a day.
It’s all expensive and time consuming. Of course, LEDs have had a major impact. Now lamp life is greatly extended, saving the expense of changing those relatively cheap bulbs. But, to get the benefit, the entire fitting has to be changed to an LED head – another expense and one which can shut the railway during the changeover process.
So what’s needed is the best of both worlds. When a bulb blows, the usual steps are taken to replace it, but with an LED equivalent. Now lamp life is extended, power consumption is also cut, and without the time and expense of changing the fitting. Utopia?
Not at all. Products from the Goodlight™ LED lighting range from LED Eco Lights have now been approved for use across Transport for London’s network in both Section 12 (underground facilities) and non-Section 12 areas, such as the tube, rail and bus stations, depots and bus shelters.
The two approved products are Goodlight T8 LED tubes, which are mandated for use where LED tubes are required in all non-section 12 areas, and Goodlight G360 LED SON replacements which can be used anywhere on the network.
Available in warm, daylight and natural colours, the Goodlight T8 LED tubes are specifically designed for retrofitting into existing fittings. Available in 2, 3, 4, 5, 6 and 8-foot lengths, the new LED tubes operate independently of external control gear. With translucent lens covers, they look just like fluorescent tubes and, once installed, deliver a bright, even light spread with no shadowing.
Specified output of 105Lm/W leads to direct energy savings up to 75 per cent. Lighting output ranges from 10W, with the 2-foot T8 tube, up to 35W for the 8-foot model. Their operational rating of 50,000 hours equates to a lifetime of approximately 20 years at seven hours a day, 11 years at 12 hours a day, and five years or more at 24 hours a day.
The new LED tubes can even do things the traditional fluorescent can’t. The ‘emergency’ option, which comprises a compact, slim-line battery/driver module, will power the tube for up to three hours – removing the need for a secondary emergency lighting system.
The Goodlight G360 LED SON lamp range has been designed to provide retrofit LED replacements for standard E27 and E40 SON and metal halide lamps usually associated with industrial lighting applications in high and low bay lighting, or for exteriors in bollards and street lighting.
The range pioneers MagLev Fan Technology (a patented design), plus a unique new heat sink design, to draw away waste heat. This unique combination provides inimitable new design with performance; delivering a long, unrivalled lifespan allowing the lamp to operate at temperatures beyond 70°C.
Both lamps have a lifetime of 50,000 hours or eleven years of use at twelve hours per day, deliver efficiencies of up to 80 per cent and are covered by a comprehensive five-year warranty.
In addition, they are almost silent in operation, under 0.5dB.
Commenting on the TfL approval, project director Dr Leon Smith said: “The network is transitioning to much greater use of LED lighting, partly because of its energy efficiency, but mostly due to the huge savings in maintenance and labour costs more advanced technologies allow. This reflects our new approach to procurement, taking a long term view and looking at the whole life-cycle costs for all the products we install across the network.”
He continued, “We rigorously assessed products from many world leading lighting suppliers and as a result of this process, we are delighted to confirm that two Goodlight LED products met our high standards; products that we will be actively using to secure savings.”
Philip Edgecombe, commercial director of LED Eco Lights, commented: “We are delighted that our products have met with the quality and performance criteria specified by the London Underground and Transport for London.
“As an organisation, TfL manage, maintain and operate in lighting critical environments, servicing millions of passengers annually. No one understands lighting better than they do. Their commitment to health and safety excellence is exceptional and the testing procedures they carry out are unrivalled.
“We are proud that they have selected Goodlight LED lighting products for use on their network, and look forward to supporting their lighting strategy.”