The new lighting, designed in accordance with the council’s specifications, covers Coventry’s residential roads, minor and major traffic routes, city centre, car parks, subways, parks and other public areas.
Balfour Beatty has now installed a total of 26,000 new street light columns and lanterns, and replaced 6,500 illuminated traffic signs and bollards with LED versions (or in a few cases removed the lights from them). 5,000 columns that were less than five years old have had their lights upgraded rather than being completely replaced.
The lighting equipment was supplied by Dutch manufacturer Philips and UK firms Orangetek, Designplan and Simmonsigns. The control system was supplied by UK-based Mayrise Systems (which has since become part of Yotta), using wireless remote monitoring technology from Telensa, which is also based in the UK.
Where possible, lights have been left in the same positions as before, but in some cases they have been moved, changed in height, or had extra lanterns added to existing columns, to provide the right levels of light.
Residential streets have mainly been lit with white light, which renders colours clearly, making it easier to recognise cars and people, and creating a more comfortable atmosphere. The lights on a typical street use 45W or 60W lamps on six-metre columns, while wider roads have 90W lamps on eight-metre columns.
Busier traffic routes use brighter lights on higher columns: 150W at 10 metres, or 250W at 12 metres. These routes use different lamps that give a more yellowish light, but are more efficient.
Seventy-five high masts light the ring road that circles the city centre. In the centre itself, 18 high masts replace 200 standard light columns, reducing street clutter and using less energy.
The lights are designed to direct light downwards, to ensure light is not wasted, and to minimise any spillage of light on to private property or into the night sky.
A big advantage of the new lights is that they can be dimmed automatically when roads are quiet. The introduction of dimming meant the council had to balance its aim of cutting energy consumption with reducing crime and the fear of crime. To get this balance right, it conducted trials and assessments over three years on the impact of dimming.
Coventry is believed to be the first city in the UK, and one of the first in the world, to have installed a central management system (CMS) to remotely monitor and control its street lights. Wireless communication nodes attached to individual lights link them to a network of base stations, which in turn are connected to computers at the command centre.
The CMS controls dimming, and tracks the operation of all the lights, recording how much energy they use and detecting signs of faults early. This means lights can be fixed before they even go out, so it is longer necessary for teams to scout the city looking for broken lamps. The system enables the Balfour Beatty team to respond quickly to failures, meeting demanding targets set by the council.