‘One supplier’ solution for the QE2 Bridge
Connect Plus Services identified the need to upgrade the original street lighting of the Dartford Crossing, originally installed in the early 1990’s and the bridge was opened in 1991. Connect Plus commissioned Mott McDonald Southampton with a brief amongst many other upgrades, to re-light the crossing using existing positions of the 192 lighting units.
In conjunction with the LED upgrade the replacement of the original CU Phosco Lighting columns mounted on the bridge parapet, 6km of new cabling and new cable management system were replaced, which in the long term made the scheme cost efficient compared to replacing the different assets at different times.
Mott McDonald had to re-use the original column spacings and acknowledged that the Phosco P851 Led was the most suitable luminaire available with its low glare reflector system (achieving G6) ideal for the bridge users and local environment. The LED’s were replacing 150w (180 circuit watts) HID products with the output of the designed P851 being 95w (with CLO enabled) offered a huge energy savings coupled with the additional control of a Central Management system CELTek supplied by Charles Endirect Ltd.
CU Phosco Lighting also assisted in the re-design of the lighting columns utilising Flanged based special Tapered Tubular columns for longevity of life and to fit existing plinth bases on the out edge of the bridge parapets. As part of the lighting design, the height of the lighting columns were also reduced to 10m.
Results and Benefits
Replacing both Lighting columns and luminaires within this upgrade provides Connect Plus Services with minimalistic maintenance schedule and cost on the lighting for several years to come. The columns were designed to a minimum of 40 years and the luminaires a life expectancy, of approximately 24 years. The columns were coated in a very hard-wearing Poly Siloxane Finish (PSX) paint finish and expected to not be re-painted for at least 25 years. This was essential as re-painting columns on the bridge is a very costly and a high safety issue, due to the location of the columns mounted on the outside edge of the bridge structure.
The luminaires are designed to require minimal maintenance over the life expectancy of the product. Again, this provides the client with limited maintenance costs and safety issues again. The advance to LED technology versus the original luminaires would provide substantial energy savings for the client, which was a key driver on the scheme.