Street lighting

[jj4091]

I always thought that street lighting was on un-metered supplies & presumed councils were billed by the number of lights they had.
Recent publicity suggests they are switching lights off or dimming them in order to save money, but I can't see how that would work unless they are supplied in a different manner than I thought. Can anyone enlighten me. Thanks

 

[bernardgreen]

The equation uses

the number of lamps.
the length of time each lamp is on
the wattage of each lamp.

if there are say 100 lamps each of 50 watts on the same time switch then for convenience they could be put into the equation as

1 lamp cluster 5,000 watt rather that enter each individual lamp.

Some councils do use the cluster method but a few apparently list each individual lamp.

 

[Spark123]

I think it just depends where you are, some I think are run off time clocks in the sub station and others are just on a photocell off the normal street mains.

 

[john4703]

Recent publicity suggests they are switching lights off or dimming them in order to save money, but I can't see how that would work unless they are supplied in a different manner than I thought. Can anyone enlighten me. Thanks

If the lights are off then there is no power used so a lower cost to the council, if they are dimmed again a lower cost.

 

[westie101]

The equation uses

the number of lamps.
the length of time each lamp is on
the wattage of each lamp.

At present the length of time will be described as "dusk to dawn" which is when the photcells operate.
In future it could well be "dusk to midnight and 05:00 to dawn" or something like that.
Whilst there are still some operated from time clocks, now replaced with photocells in substations these are being phased out

 

[mattylad]

In that case the lighting bill in Rossendale will be very low, they turn them off at night.

 

[phatboy]

They are generally un-metered. When a new lighting technology (dimming, gas discharge ,LED) comes out, 1 or 2 random units can be metered to get an average reading over 12 months. The billing is then back dated and adjusted to be correct.

At least in Jersey it's done that way.

 

[jj4091]

others are just on a photocell off the normal street mains.

As ours are, or at least when they work. It seems that half of them are on 24 hours/day & many don't come on at all.
This is what is confusing about saving money, as there seems no real way to control them or accurately measure costs. Thanks all.

 

[OwainDIYer]

Turning them off will also extend lamp life, reducing re-lamping costs. As councils generally have high labour costs, that may be significant.

 

[mattylad]

It doesn't help when driving with them off - we have to turn our headlights on then!

 

[westie101]

Regarding charges when they are faulty.
Over the years those that are on all the time (day burning0 have been found to balance those that don't work so it ends up cost neutral

Though the biggest difficulty that councils have is that folk on the whole can't be bothered to report the faulty ones, but then start complaining if they are faulty for some time.

 

[StudWall]

yes most of the street lights in the UK are un-metered.

The new LED lights often have built in technology to the LED drivers which determine the date and time of day based on when the photocell switches on / off and can dim at the correct time accordingly. search "Philips Dynadimmer" or "Osram Astrodim" for more info, this means no clock is needed.

samples of the street lights are measured in a lab for the various dimmed levels so that the correct power usage is known, this is them submitted to the administrator Elexon for appropriate charging ... search UMSUG for details (UnMetered Supplies User Group)

how do i know ... my day job is measuring street lights in a lab for exactly this purpose

 

[RF Lighting]

What happens with Christmas lighting supplies? I install the column mounted motifs for the parish council in our village and connect them to the existing commando outlets which were installed by the council years ago.

Are these somehow factored into the streetlight power usage calculations as the motifs can vary from year to year.

 

[jj4091]

Though the biggest difficulty that councils have is that folk on the whole can't be bothered to report the faulty ones, but then start complaining if they are faulty for some time.

Not true around here, it is more a case of the council can't be bothered to send anyone out despite repeated reports or the guy fixing one lamp is not allowed to or can't be bothered fixing the faulty one 30 yards down the street when he can see it is on constantly.

 

[StudWall]

What happens with Christmas lighting supplies? I install the column mounted motifs for the parish council in our village and connect them to the existing commando outlets which were installed by the council years ago.

Are these somehow factored into the streetlight power usage calculations as the motifs can vary from year to year.

nope, these will have to be on a metered supply.

And the councils don't like repairing lights that are on 24/7 (known in the trade as dayburners) because it costs them, and they aren't charged for the extra electricity anyway