Advanced lighting technology allows online control of streetlights
As some councils consider turning off one in every ten street lights, EnLight provides a solution that slashes energy bills while actually improving the service we get from our streetlights. EnLight allows remote control of all streetlights, so they can be lit and dimmed from a central point, and faults can be detected remotely, making an engineer’s job more efficient.
David Aarons is managing director of the Norfolk company. He says: “If a street lamp is dimmed by 20% you won’t be able to detect the change, yet for every £5 you were spending on electricity you now only spend £4. Councils could save money by, for example, dimming their lights in the early hours of the morning when there are few people about. Our system gives them automatic control and enables them to save energy without turning off street lights.”
Extensive field-testing has been completed and production is now under way with several local authorities already showing interest in trialling the unit.
All the lights in each district (which could be a street or a whole village) are linked to a ‘cluster controller’. From this central location it is possible to access information from each light – such as the outside temperature, the daylight level, and whether there is mains power. This means diagnosis of faults can begin from the office.
David says: “Our system has great potential to reduce the time and money spent on sending engineers out to fix things. Tragically, every year streetlight engineers are killed or injured through electrocution. We allow diagnostics in the office that you currently need to do up a lamppost, thus reducing safety concerns.
“We can tell, for instance, whether the fault is with the lamppost or the mains supply. If the problem recurs at particular times, the engineer can be sent out then to ensure they are there when the fault occurs. The position of each lamp is overlaid on Google maps, and viewing the surroundings helps the engineer predict the kind of problem they may encounter. The system can be set up to send an email to an engineer whenever a fault is detected.”
The cluster controller contains a web server so information about every streetlight can be accessed through an online interface. Each light is represented in a traffic light colour: green when it’s working, amber when there’s a temporary fault, and red when the lamppost is disconnected. Clicking on a light will reveal more information – including graphs showing when the light has been on and historical records of any faults.
All street lights are fitted with an electrical ballast, a small box which limits the amount of current in the electric circuit. This ensures the current is constant so the light is stable. David says: “Normally a lamp sucks more electricity as it gets older, but our ballast ensures a consistent electricity supply whatever the age of the bulb.”
The novel electronic design also provides additional energy savings. The Entelli-Ballast has an overall energy efficiency of 95%, compared to 85% for the closest competitive electronic ballast and 50% for the older style magnetic versions.
A light sensor sits on top of the street lights, ensuring that the light comes on when it gets dark. Sophisticated software within EnLight’s sensor can calculate the time, so lights can be dimmed automatically at midnight without needing a clock.
There are 200 different types of lamps used in British streetlights and they all require different ballasts. As councils come to upgrade their systems they therefore have to buy new ballasts as well as lamps. But EnLight’s Entelli-Ballast can be retrofitted to any lamp, so can easily be used to upgrade a system without having to start from scratch. Savings on electricity and transport to fix faults mean the system will pay for itself in approximately three years.
Written by Rachel Holdsworth