Just wondering, What type of streetlighting do you have around where you live?. The reason I ask this, is, I was reading an article in a Trade magazine recently, that stated that where the street lights had been upgraded to Metal-Halide, there was a distinct decrease in the number of pedestrians hit by motor vehicles. The authorities that had the upgrades done also noted a decrease in the amount of energy used over a period of 3 months, as opposed to the Sodium Vapour lamps that they replaced. What are your thoughts on this subject, as Street lighting is one thing that is often taken for granted(until it fails!). But if a few lives can be saved, in the process, it's got to be good, eh?.
Flourescent, on highly frequented streets and crossings sodium. Maybe metal halide is used on the oldfashioned candelabers in the inner city, they are on very high poles and give off an almost white light, so I guess either metal halide or mercury vapor. Typical is a batten with 2 flourescent tubes, hanging from 3 bare wires above the middle of the road. 1 tube is switched off at midnight. Some time ago in front of our house the tube that remains on all night blew in 2 adjacent fixtures, so it was completely dark.
Re: Street-lighting?#136526 04/10/0306:04 AM04/10/0306:04 AM
Over here in Ireland they're almost exclusively sodium lamps except in some city centre locations where an orange glow is considered a little on the ugly side and a white flourecent or high powered "architectural" white uplighters are used on buildings and bridges.
Old lamps were mercury based and were gradually phased out as they're considered an environmental hazard. Disposal of large quantities of mercury containing tubes poses a big problem and is quite expensive.
The older mercury lamps also didn't really throw out enough light. Sodium bulbs can be much brighter without being irritating.
Re: Street-lighting?#136527 04/10/0306:22 AM04/10/0306:22 AM
I've also seen single round lantern-style fittings "strung" between poles that hung in the centre of the street. Not too many of them around anymore. They looked cool though. Much more ornate than the modern ones.
Gas street lighting has re-appeared in some locations too. It provides a really soft light and it's much more ornate. It's used exclusively in Dublin's phoenix
Normal Dublin Electric (usually sodium) street lamp.
(Standard Dublin Street lamp)
Re: Street-lighting?#136528 04/10/0306:24 AM04/10/0306:24 AM
In Sweden you only find the yellow lamps on highways. Most street lights have a type of bulb that takes a quite a few seconds to start: the light goes frome reddish to bright white in the process. You pros should now be able to tell me what it is
dkj, those are beautiful lamps! *envy*
[This message has been edited by C-H (edited 04-10-2003).]
C-H i think the lamps you are on about would be High Pressure Metal Halide,
as to lighting in England, it really depends on were you are,
In my town (Southampton)we have a varity of fittings and lamps.
Motorways, (were lit) are high pressure sodium usually 4 x 400watt each arm.
class 1 roads; high pressure sodium, from 150, 250w and 400w single lantern at heights of 4m to 10m
class b roads; 35watt low pressure sodium (a horid light but excelant lamp life)
But in the city they are slowly being changed to 100watt Metal Halide and 400 watt in the main city streets, (as the city now has CCTV it helps to see the local idiots on a weekend after the bars shut)
but we still survuve on 35, 55, 90 and 135 watt low pressure sodium lighting on most streets, and out in the wilderness of the new forest etc.
me personally,? change em all to Metal Halide, good clour rendering and an all round good light, and you can get colours for them as well.
The majority of street lights in the US are sodium, as are the majority of utility-owned parking lot floodlights.
However, privately-owned parking lot lighting tends to be metal halide.
You will see, on rare occasion, an ancient mercury vapor street light that has not been replaced yet.
If I might add an interesting side note, the street on which I used to live actually had incandescent street lamps up until the early 90's, with huge 300 or 500 watt mogul based bulbs. They were replaced with sodium lamps.
indeed most area still use 100 watts hps but in cities it can varis from 100 to much as 400 but some case i see use a thousand watt bulb (1,000w) bulbs but right now few area in cities are staring to switch over to metal halide now but with new one comming out is pulse start mh i personally like them they do kick more light than old mh type and as far for old mercury vapour light that about complite history expect for privte owned fixures and flourest light it is mixed bag here but flourscent light is not too wonderfull in northen state due cold weather
Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)
CT wireman — Were the street incandescents the "series string" type? They were popular during the days of penny-a-kilowatthour electricity, along with “mica shots” flashing/hopefully shorting when a lamp filament failed.
Side note: One [minor?] limitation of M-H lighting is its [pitch black in the mean time] 15-minute restrike time after power interruption/restoration.