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Posted By: diggingdeeper Street Lighting - again - 2nd Jan 2017 2:34am
Wirral Council have recently admitted that they know of 1758 unlit lamp fittings - I suspect that the actual numbers of defective lamp fittings may be three times that figure.

Despite all the noise they made last Autumn/Winter about examining all lights and would fix them all by May(iirc), I have seen many lights that were not fixed.

This financial year they have already fixed 3673 fittings but I know they have many to go.

More details and figures can be seen HERE

Of interest is Section 4 of the response where they state they have not spent one penny during the last two and a half years on "money spent on bulk light changes as part of maintenance of Wirral street lighting".

Section 5 would also indicate that the recent LED replacement program has only included 20% of fittings.
Posted By: pacef8 Re: Street Lighting - again - 2nd Jan 2017 9:25am
No mention of which ones they have deliberately switched off then.
Posted By: Excoriator Re: Street Lighting - again - 2nd Jan 2017 1:06pm
Quote
No mention of which ones they have deliberately switched off then.


At least they have been on once. Drive along the New Ferry bypass and enjoy a section where they have NEVER one been on since installation!
Posted By: Norton Re: Street Lighting - again - 2nd Jan 2017 4:56pm
Another interesting find, DD.

Even more interesting is the fact that most lights cost between 3 and 10 times more to run when they are dimmed!! Surely, in most cases, brighter lights would mean fewer lights for the same level of illumination?

Is there no guarantee from the contractors used in the LED conversion, making them go back and repair faults on their work, within a certain time?

If you and I were paying contractors to do work, wouldn't we get them back to sort out what we'd paid for until it was right?

As ratepayers to this Council, we have paid and should be demanding our moneys worth with robust service levels and quality management in place.

And as to the money we paid for street lighting in the past two years that didn't get spent - could someone shine a light on that?
Posted By: Excoriator Re: Street Lighting - again - 2nd Jan 2017 5:36pm
140w Ceramic Metal Halide - CPO £68.36
140w Ceramic Metal Halide - CPO bright £6.32
140w Ceramic Metal Halide - CPO dimmed Low £38.20

Can anyone make sense of this?

The less energy you radiate, the more it costs! Presumably, they cost even more when they are switched off!

The mind boggles! Perhaps Ms Paterson, the Senior Information Management Officer (Business Services - Digital) can shine a light on this oddity.

It is worth noting that there is skill involved in answering freedom of information requests. It consists of making sure that the answer - whilst not overtly dishonest - is incomprehensible to the extent where no real information is released. Studiously avoiding any clue as to what CPO, CLO and CDM mean (if anything) leaving the enquirer guessing is typical of this sort of obfuscation.
Posted By: keef666 Re: Street Lighting - again - 2nd Jan 2017 6:48pm
When i have paid my last Council tax payment this week for the last year, i am going to ask them for a refund on account that some of the lights by me have been off for the last 14 months, workmen came out last year changed the bulbs to LED's andthey still never worked, amzed no one has had a crash or been run over as they are on a bend, maybe then the Council will get off its arse and fix them, and don't get me started on potholes!
Posted By: Papa_Juliet Re: Street Lighting - again - 2nd Jan 2017 10:45pm
Originally Posted by Excoriator
140w Ceramic Metal Halide - CPO £68.36
140w Ceramic Metal Halide - CPO bright £6.32
140w Ceramic Metal Halide - CPO dimmed Low £38.20

Can anyone make sense of this?

The less energy you radiate, the more it costs! Presumably, they cost even more when they are switched off!

The mind boggles! Perhaps Ms Paterson, the Senior Information Management Officer (Business Services - Digital) can shine a light on this oddity.

It is worth noting that there is skill involved in answering freedom of information requests. It consists of making sure that the answer - whilst not overtly dishonest - is incomprehensible to the extent where no real information is released. Studiously avoiding any clue as to what CPO, CLO and CDM mean (if anything) leaving the enquirer guessing is typical of this sort of obfuscation.


I'm no street lighting expert, but a search of the above abbreviations associated with street lighting revealed the following:

CPO - Philips CosmoPolis™ (CPO) Outdoor Lighting System
See Philips CosmoPolis

CLO - Constant Light Output
See Philips Unistreet LED Lighting system

CDM - Ceramic Discharge Metal Halide
See - Ceramic Discharge Metal-Halide lamp

The Philips 140w Ceramic Metal Halide lamps appear to be incredibly efficient in terms of lumens per watt, producing up to 16,500 lumens of white light for 140 watts which is as good as the best LED's but requires a reflector to redirect light down which reduces output due to light being trapped in the housing. There is no indication in the datasheet that the lamp uses more power when dimmed, but it is slightly less efficient, requiring 60% of the maximum power when the light is dimmed by 50% so I suspect there is an error in the annual running cost figures shown in your FOI reply for these lamps, my guess is the annual cost at full output should be £68.36 and at 50% output £38.20 which roughly lines up with the datasheet figures.
Posted By: diggingdeeper Re: Street Lighting - again - 2nd Jan 2017 11:03pm
Originally Posted by Papa_Juliet
The Philips 140w Ceramic Metal Halide lamps appear to be incredibly efficient in terms of lumens per watt, producing up to 16,500 lumens of white light for 140 watts which is as good as the best LED's but requires a reflector to redirect light down which reduces output due to light being trapped in the housing.


But a low pressure sodium would produce 29,400 lumens for that wattage albeit not white light.

Low pressure sodium is still the most efficient light source in many power ranges, an LED would be very lucky to get 14,000 for 140W.

What they are hoping for LED is that the life is greatly increased, the efficiency isn't as good but it is dimmable which can give a cost saving.

This graph is slightly out of date for LED efficiency but the order is still correct ...

[Linked Image]
Posted By: Excoriator Re: Street Lighting - again - 3rd Jan 2017 8:36am
New white LEDs claim around 100 l/W, but in theory could soon produce about 250 l/W.

Also of interest are laser illumination which can produce around 170 l/W

(See http://www.ledsmagazine.com/article...er-alternative-to-led-light-sources.html)

Something which doesn't seem to have occurred to our council, however, is that whatever light source you use, if the thing is broken, you get NO light from it until it is repaired.
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