Although it does not provide a magic solution, LED technology is nevertheless becoming a must and is constantly evolving. Sibelga now has 95.4% of its public lighting fitted with the most efficient bulbs (2017 figures) and these are equivalent to current LEDs in terms of efficiency. The systematic replacement of equipment is therefore not urgently required, but we do need to be willing to prepare for it in the best possible way, taking all the issues raised into account.
An essential technological development
Manufacturers, concerned not to miss the critical point of this development and pushed by current and future EU Ecodesign directives, have staked a great deal on LEDs. So much that it will soon be impossible to buy anything else... and mandatory to opt for LED lighting.
A technical, logistical and IT challenge
LED street lamps are more complex to troubleshoot than current street lamps. In most cases at the moment, a single site visit is sufficient for Sibelga staff or contractors to solve most problems. Typically this involves replacing the defective part, which is standardised and easily removable, with an identical component. Repairing LED street lamps may, however, require several successive visits, and they may even have to be returned to the factory. This is without considering that LEDs bring us into the world of electronics, so certain components will have to be reprogrammed. Suffice it to say that setting up the logistics chain to follow the path of different street lamps between removal and reinstallation in their original location is not an easy task, not to mention the developments to be integrated into the computer database that manages all the installations.
Sibelga currently estimates the lifespan of LED lamps at 15 years, compared to 25 years for traditional lamps. This means a higher replacement rate for lamps to keep the network in good condition, not to mention the fact that their average cost may be €195 higher than their counterparts using traditional technology. In addition, for small-format design lamps, temperature management means the power of the device must be limited. This has meant that for some projects, Sibelga found it had to install two or three times as many lamps (although of reduced power) to reach a lighting level complying with the standards.
Did you say no maintenance?
Many suppliers boast that LED equipment does not require maintenance over its lifetime, unlike current fittings that require lamp replacement every three or four years. But this does not take into account what really happens when the lamps get dirty. On the basis of field tests, Sibelga – like other distribution network operators – has come to the conclusion that regular cleaning is required. Ideally, this will be done every four years.
The unseen problems
At least, not to the with the naked eye. With current lamps it's easy – either they work, they flash or they don't work – and this is visible to the naked eye! LED lamps consist of a set of diodes. Some may work and some may not, without anyone noticing. But Sibelga must nevertheless guarantee the presence of a certain level of light. It is therefore necessary to set up an Intelligent Street Lighting system* capable of raising the alarm when a lamp is no longer offering the expected amount of light. We cannot rely simply on the attentive eyes of local residents.
Most LED lamps are available in white, while orange ones are significantly less efficient. This means that, gradually, as of January 2018, the entire network of lamps will be replaced in white. This will ensure uniformity of colour if classic and LED fittings have to coexist in the same street.
Sibelga is now preparing to welcome this new technology. In addition to the tests carried out, we are working on a new public tender to include LED lamps. As such, we will have to negotiate firmly with manufacturers to achieve commitments on prices, availability of ranges, guarantees, and other issues. We are developing a new computer application and reviewing our processes and working methods. Staff and teams of contractors now have to be trained before we can roll LEDs out generally on our streets. This is planned from 2019.
*Communication system to remotely manage the switching on and off of street lighting and to obtain feedback on the state of the network. This system can be operated via electrical cable, radio or GSM network. It can build in different types of sensors or dimming scenarios.