Having worked in the lighting industry for just shy of a decade I have come across a varied manner of electrical supply to street lighting columns, the main source of an electrical supply into a street lighting column is by the Distribution Network Operator (DNO) this method of connection is in my opinion the best solution to authority’s as they never need to worry that they will have to replace the mains cable if the fault is with the DNO side. Many times I have seen connection faults and the average turnaround time for DNO’s to get them fixed is within 20 working days.
During working on the Derby Street lighting PFI I came across 5th Core cable which seemed a “grey area” in that the DNO wouldn’t take responsibility for the cable until it was made live on their network. After that happened the DNO were then rather reluctant to joint onto the 5th Core cable due to the earthing of the cable and vintage being rather antiquated. This also caused trouble when replacing columns as some of the columns being replaced were control columns for adjacent streets and caused faults on the 5th Core network. My advice if organisations is to totally replace this network and look to replace with DNO new connection if available or cost effective.
Another way of feeding columns is by Private Network Cable (PNC) which is usually owned and maintained by the local authority or developers, this is a viable option if there is little or no DNO in the area. However as stated in the new DNO connection this cable will not be replaced in the future by the DNO and will incur costs to the owner of the PNC if the cable fails. Also with PNC is that if required by other organisation’s the owner of the PNC is required to show indicative locations of the PNC in as built drawings.
In recent years manufacturers of street lighting products have explored the possibility to run lanterns via solar power using batteries to be charged up during the day by solar arrays, this at the present time is a very costly method and is reliant on the sun. In the UK we have rather unpredictable amounts of sun light and time will tell if this is viable. This also is the case for wind powered street lighting assets which are charged in a similar way to the solar method but would require more maintenance.
Ultimately all local authorities are looking at ways to save energy and maintenance costs within strict budgetary requirements, this will not change anytime soon and I hope this blog explains the different connection methods.
Rob Cooper, Derby