Waiting for the sun to go down is something that many Lighting Engineers grow accustomed to during their careers. However, it is less often that they are joined by curious crowds of residents, contractors and Council officials.
The purpose of the assembled party was to witness a clever demonstration where observers would be able to compare traditional street lighting with an LED solution instantly alongside one another.
The ‘seeing is believing’ concept was designed by Rob Warner of Middlesbrough Council and installation contractor, David Webster Limited.
Indal WRTL Exterior Lighting Limited invited spectators along to the residential street to observer the immediate contrast between the existing 10 x 70W SON and 3 x 35W SOX lanterns and 11 x recently installed Stela Wide 36 LED luminaires.
To begin with there was nothing new to see. The onlookers saw houses and the street bathed in the usual golden glow that washes every road and to which everyone has grown accustomed. This was shortly followed by a stunned silence as the street lighting switched from sodium to LED lighting.
The scene was dramatically and instantly transformed. At once everyone could clearly see to the ends of the road whereas moments before the street had faded into the shadows within a relatively short distance. The level of light delivered by the Stela LED luminaires was consistently uniform, which in turn enabled the undulation of the road to become visible and hazards become identifiable. The crystal clear quality of the cool, white light offered excellent colour definition and it was possible to see the undistorted colour of plants and flowers.
Evidence of accurately-controlled light fall could also be seen. Objects cast shadows into gardens but no obtrusive light, classified as statutory nuisance in Scotland, reached the front elevation of the properties. Behind the street lights there was no more than around 3m of light fall, eliminating spill and light pollution. Although this installation was a bright S3 design, there was no glare from the Stela units and each LED was clearly visible.
Probably the most dramatic evidence of the evening was provided by an LCD display mounted on the feeder pillar that showed the energy output in total circuit watts. The party were invited to note the reading on the meter before the switchover had taken place. This was taken as 1.15 kW. No sooner had the transfer taken place then the reading changed to 0.55 kW - a reduction of 52%.
Such was the level of disbelief, the crowd asked for the demonstration to be repeated. It took more than 5 minutes for the orange glow to reach full power and the sepia scene to return, at which point the energy consumption was again more than double.
Finally, the Stela LED street lights, designed to meet EN60598 standards, were switched on again - this time to a resounding applause. Everyone now wanted to know the facts behind the spectacular comparison and commenced firing questions at contractors and lighting
This installation will reduce maintenance costs by more than 66% and only four column visits are anticipated over the next 25 years.
If there had been any sceptics at the beginning of the demonstration they had been convinced by the time the crowd departed. Everyone present could see that whereas they might have witnessed magic, there was certainly no trick involved. The genuine and dramatic performance improvements, energy savings and CO2 reductions that Stela LED lighting can deliver were there for all to see.
Stephen McCluskey, Coventry City Council Service Manager, commented: “This is a very impressive scheme with good uniformity levels.” Bedfordshire Highways Electrical and Lighting Manager said: “I was very impressed with the installation and it was a pleasure to witness the switchover. Indal WRTL are leading the LED programme.”
Date of release: 01 March 2010