UK To Dim Highway Lights To Save Money 348
Hugh Pickens writes "The Telegraph reports that street lights on thousands of miles of major roads in England will be dimmed during quiet periods to save money and reduce carbon emissions. The Highways Agency has already turned off the lights on more than 80 miles of the motorway network and will soon begin a survey of where this can be done on the 2,500 miles of A roads it controls. Nigel Parry, of the Institution of Lighting Professionals, says that technology enabled lights can be controlled individually and remotely. 'The idea is that when traffic is busy, such as during the morning and evening rush hour, you have them at their brightest. When the traffic disappears you can dim them. You can maintain safety and use half as much energy.'"
I for one (Score:5, Funny)
I might just be a luddite, but (Score:5, Insightful)
It would thus make more sense to not have lights during high traffic times.
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No, I was thinking the exact same thing. Unless someone is either an idiot or recently experienced a taillight outage, you should have no problem seeing them at night. Unless they are a person, or a deer; the safety of which is exactly what makes street lights most useful.
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No, you're exactly right - they have it backwards.
Now the lone driver at night is at serious risk,a nd the people during traffic which already are experiencing light pollution continue to do so. At the same time, they save money!
profit! except not in the long term due to increased crash risk.
Re:I might just be a luddite, but (Score:4, Insightful)
Because headlights only light up what is in front of a car, not what it to the side of it. A roads can be dual carriage ways, remember. You also have to account for unsafe driving, which is more likely and more dangerous where the road is packed.
Re:I might just be a luddite, but (Score:5, Interesting)
>Because headlights only light up what is in front of a car
Correct. It's worth mentioning, for the benefit of our cousins, that we British drivers tend to change lanes much more often than Americans.
Until very recently, it was mandatory in the UK to return to the lane furthest from the median immediately after overtaking. Only very recently has this been changed to allow you to remain in the centre lane for extended periods. In the UK it is still illegal to hog the lane nearest the median and it is illegal to "undertake" (i.e. to overtake on the furthest lane from the median) unless you are using a ramp/exit/sliproad.
So in the UK where we drive on the left, you can only overtake on the right and most people have been trained to return back to the left pretty much immediately. That makes visibility (and therefore lighting) of the whole width of the road vital during busy periods.
My experience of driving in the USA is that overtaking is allowed on any side and that most motorists pick one lane and stick to it for most of the whole journey, regardless of speed. (Re-wrote this half a dozen time to try to get the terminology UKUS neutral. Probably still not quite right. Bah.)
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Actually, US laws are pretty much the same as what you describe: the lane closest to the median is reserved for passing, and what you call "undertaking" is illegal. We also have a law requiring you to change lanes to allow someone to overtake, if you can safely do so. There are signs posted all over the place saying "Slower Traffic Keep Right" to remind people of this law (remember, right is farther from the median in the US).
The difference is that these laws are basically ignored by both drivers and poli
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Because headlights only light up what is in front of a car...
TFA is about the UK. They drive on the wrong side of the road, so the headlights light up what is behind of the car.
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Americans drive everywhere .-)
Using the footpath is what you do when crossing from your Hummer to Walmart to stock up on lard and chip fat.
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You realize that pedestrians and bicycles are prohibited on most (if not all) US Highways? (and I mean the real ones, like I-75 - not "highways" by name)
There's a sign on the on-ramps that tells you what is and is not allowed on the highway.
Re:I might just be a luddite, but (Score:5, Informative)
It benefits pedestrians much more than drivers, but the lights make it easier for drivers to see where they're going too. Without street lights, the area outside of where your headlights land will be dark if there's a moon, or a pitch-black void if it's a moonless night, vs. with street lights where the whole road is lit up.
Re:I might just be a luddite, but (Score:5, Interesting)
Without street lights, the area outside of where your headlights land will be dark if there's a moon, or a pitch-black void if it's a moonless night, vs. with street lights where the whole road is lit up.
Your point about the interface between the lit and the non-lit is correct, but it has unintended consequences. I did a fair amount of research into street and highway lighting as part of astronomy related "dark sky" issues. Some things are counter intuitive. It would seem that the brighter the light, the better and safer the roadway would be. That might be true when entering a well lit area, but upon leaving it, you will see much less until your eyes adapt.
It's a matter of intuitively and practically knowing that daylight is best for vision. But we cannot afford to light up the globe to daylight levels. So we try spot lighting, which doesn't work all that well. In addition to the light/dark interface, we often have the light source being visible to the drivers. Given the intensity of the light hitting the surfaces versus the intensity at the source, your eyes will adapt to the source. So it is always safer to have shielded lights if you have them.
There is a particularly pernicious "brighter is better" issue going on right now with the new headlights that are very bright and focused. Unfortunately, this transcends from the counterintuitive to plain stupid. The light beams are so focused that differentials in height can blind you. My first experience with one of these "gamma ray headlight" vehicles was being followed by a person down a country road with a lot of bumps. Every time his car was a little higher than mine, it would look like he was flashing the high beams. It was very distracting Worse is when they are coming toward you. The opposing driver might have their low beams on, but if they are at the crest of a hill, and you are coming up the hill, you get treated to a blinding flash of blueish light. I wonder about the safety of a blinded driver coming straight at you. Apparently the designers came from flatland.
But it is the same thing as the "er" effect used so well in marketing. Bigg-er, Bright-er, Bett-er. It;s hard to convince everyone that brighter isn't safer.
I think that dimming the lights might actually make the roads safer. Oops, there's that -er again!
crazy bright headlights, streetlights (Score:3)
No, the problem is just as bad here on the plains. Our roads have bumps too, braking causes vehicles to dip and rebound, acceleration causes them to rise and fall back, you can't tell the difference between a focused beam sweep and a highbeam flash, and the whole thing is significantly distracting when you really need to be paying attention to other issues, such as the facts that your iris is now contracted more than you're used to, your vision into darker areas
Re:I might just be a luddite, but (Score:5, Informative)
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At 50-70mph you don't have a lot of time to react to a dropped cinderblock/plank full of nails/crazy man curled up on the highway (really happened to a friend) / crazy woman walking on the highway (really happened to me, I missed her by sheer luck).
Re:I might just be a luddite, but (Score:4, Insightful)
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That's what the Nigels think, but what about the Bruises?
I've been watching too many Top Gear reruns...
Re:I for one (Score:4, Funny)
Highway lights??? (Score:5, Interesting)
I doubt that highway lights are an actual safety improvement, considering that the german Autobahn don't have them at all.
Re:Highway lights??? (Score:5, Funny)
The Germans are in bed by 9pm.
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In winter that still means 5 hour darkness before German-bedtime. Enough time to race on the Autobahn. Nevertheless, most people are watching TV at that time. 20:00 Tagesschau (news), followed by unspeakable bad TV, followed by Tagesthemen (more noews) 22:35-23:00. However, the last news thing is only for "educated" people. the rest has to be in bed by then.
Another good reason for darkness on the Autobahn: You cannot see the special driving skills of those who inhabit the road at night. This is very importa
Night driving and special skills (Score:5, Informative)
In Montana, when during a short and unusual period of rationality we had somewhat unlimited daytime driving speeds [hwysafety.com], nighttime driving was still constrained to relatively low speeds because there is no safe driving regime that includes over-driving one's headlights. And while during the day it was kind of difficult to get a ticket when driving reasonably, at night, they could nearly hang you at the side of the road if you stepped out of line. IMHO, that was driving heaven. Accidents declined below Montana's previous levels, and other than gas milage, the side effects were pretty much uniformly positive.
Personally, we (my family) bought a relatively high-powered sports car capable of long-term high speed runs, and intentionally focused on traveling during the day, as one got to the destination faster, the driving was a lot more fun, concentration was better as more things happen faster, and said concentration, easier or not, didn't have to be maintained for as long a period.
As an aside: Daytime driving is safer here because the animals generally keep their heads down or they get shot off by our not very lovable rednecks. Often heard here: "Wanna go bust some 'dawgs?" This is a euphemism for going out and "popping" prairie dogs, and anything else that might show its eyes or ears, with a high powered rifle. This is about as popular as drinking. and often the behaviors are combined. Anyway, it leads directly to a very cautious daytime wild animal population.
Alas, the feds applied significant pressure by threatening to withdraw highway funds, our state legislators invented nonsensical justifications to accommodate the idiot feds without exactly looking like they were accommodating them, we lost our driving paradise, accident rates went right back up, and there you have it.
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Ok..we got rid of them there as a first step.
Re:Highway lights??? (Score:4, Insightful)
I only ever see the in city areas, and have driven during rush hour. That's the only time I would say they are a safety improvement. A number of idiots drive in the dusk without their headlights on out here in the country. Magnify that for city rush hour and it can get dangerous. The biggest issue is likely seeing the exit signs, so it's likely to reduce distraction of people trying to read them with the shorter range of head lights on low beams, or having people that are blinded by the high beams on behind them to get better range on the road sign reflectors.
Re:Highway lights??? (Score:5, Insightful)
You're much more likely to notice that you forgot turning on your headlights if it's dark around.
Re:Highway lights??? (Score:5, Interesting)
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I'd say that's mostly to the actual change and people being unused to the new ilumination situation.
And please keep in mind that I was comparing to the Autobahn, where nothing and noone but cars are allowed. Moving cars to be exact.
Re:Highway lights??? (Score:5, Informative)
Belgium (notorious for lighting every square meter of higway, it looks like you're driving in broad daylight) decided to turn of every other light a couple of years ago. After the number of accidents rose some 25% they quickly turned the lights back on!
Sorry, but that's definitely no longer correct.
They shut off most of it last year. Afaik it's still shut off and the reports on the effects ranged between "no noticable effect on the accidents" and "slight decrease". The light increased visibility, but the feeling of safety seemed to lead to more speeding accidents and reckless driving.
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Yeah, but no.
If you've ever driven here in Belgium, you might have noticed that ALL roads are crappy. From highways to small roads, there are holes everywhere.
Autobahn (Score:5, Interesting)
Long answer: street lights reduce the glare from oncoming vehicles, which is at its worst at busy times. On 'A' roads, they also let you distinguish motorcycles from our increasing number of one-headlamp drivers. On the other hand, I've seen the result of the Porsche that overtook me once doing at least 200k at night meeting the Polish artic with tiny lights covered in mud. With street lights, the Porsche driver might have seen the truck in time. As it was, Darwin claimed another victim.
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To me it's counter intuitive to turn the lights off outside rush hour.
During rushhour when traffic is going naturally slow, I'd thought less light was needed - but during late night you would need more light to make sure you see whats ahead of you. (High beams might help, but if there is light traffic, you might not be able to use them).
Re:Autobahn (Score:4, Insightful)
Re:Autobahn (Score:5, Funny)
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Short answer: which have the better safety records, British motorways or German Autobahn?
Controversial answer: Which roads have better drivers, British motorways or German Autobahn . . . ?
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The British drive on the right side of the car.
Re:Autobahn (Score:4, Funny)
Re:Highway lights??? (Score:5, Interesting)
I doubt that highway lights are an actual safety improvement
I've done quite a bit of driving on UK motorways late at night and in bad weather and have to say I really appreciate the lit sections. Particularly in heavy traffic with fog, rain and snow it dramatically improves your visibility and I feel I can judge distances a lot better with them. I don't mind being on an empty unlit road at night, but a busy one (e.g. parts of the M62 on the north side of Manchester) can be pretty horrible.
Re:Highway lights??? (Score:5, Insightful)
I doubt that highway lights are an actual safety improvement
I've done quite a bit of driving on UK motorways late at night and in bad weather and have to say I really appreciate the lit sections. Particularly in heavy traffic with fog, rain and snow it dramatically improves your visibility and I feel I can judge distances a lot better with them. I don't mind being on an empty unlit road at night, but a busy one (e.g. parts of the M62 on the north side of Manchester) can be pretty horrible.
I find that in the unlit sections the dazzle of the oncoming headlights is much worse. And if you have dipped beams to avoid dazzling them you are driving into darkness - you know on a motorway that the road is clear but it is psychologically stressful when you can't actually see the road ahead as far as your stopping distance.
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Re:Highway lights??? (Score:4, Insightful)
I've done quite a bit of driving on UK motorways late at night and in bad weather and have to say I really appreciate the lit sections. Particularly in heavy traffic with fog, rain and snow it dramatically improves your visibility and I feel I can judge distances a lot better with them.
I find that in fog, street lighting just illuminates the fog and prevents me seeing. Whilst my headlights also reflect off the fog, the effect is far less because they are at a lower level (especially front fog lights).
To be honest, the only problem I have driving on unlit sections of road is that when I'm following someone I can't tell if the road ahead is dark because there's no oncoming traffic (and thus safe to overtake) or because it goes around a corner. This is better resolved by installing LED cats eyes instead of streetlights, since it would show the direction the road is going in.
I will accept that some junctions and city centres benefit from lights, but most roads don't need lighting. This is true in the suburbs too - there's a lot of evidence to suggest that whilst lighting makes pedestrians feel safer, it actually reduces safety because it creates lots of dark shadows. Pedestrian safety is improved by simply carrying a torch and wearing light clothing instead of installing street lights everywhere.
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I really like LED catseyes for the somewhat silly reason that I somehow find it preferable having a stream of lights in my mirrors than nothing at all. They also seem much more visible in fog.
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The speed limit on motorways is usually 120km/hr. Almost everyone is doing at the very least 75~80km/hr.
The UK government now wants hundreds of thousands of people to do cope with such speeds, at night, in the dark, in all weathers, and I image probably even expects for this not to cause a few 10 car pileups on the odd lonely strecth of motorway somewhere.
You want to save electricity? Ban clothes dryers, electric heaters, dishwashers and electric kettles. At least you'd cost less lives than this insanity.
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Dimming the lights seems like the worst solution too. I wonder how much it would cost to install sensors to detect traffic and flip on the lights only ahead of individual cars. The downside would be bulb wear, flipping lights on and off increases the wear on incandescent and flourescent bulbs.
For a sensor maybe just have a small computer with object recognition every few hundred feet. Detecting headlights should be easy so they could be spaced far apart on the straights.
LED lights last longer if dimmed (Score:4, Informative)
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The speed limit on motorways is usually 120km/hr. Almost everyone is doing at the very least 75~80km/hr.
The guidline for the unlit Autobahn is 130 km/h where no specific speed limit is given. But that (and lower speed limits) don't result that people are expected to drive that fast under all conditions.
The UK government now wants hundreds of thousands of people to do cope with such speeds, at night, in the dark, in all weathers, and I image probably even expects for this not to cause a few 10 car pileups on the odd lonely strecth of motorway somewhere.
Here we expect people to use their brains and slow down under bad conditions. But "darkness" isn't one of them unless combined with bad weather. Without that, reflective road markings, head and tail lights and roadside reflectors give enough visual guidance.
You want to save electricity? Ban clothes dryers, electric heaters, dishwashers and electric kettles. At least you'd cost less lives than this insanity.
Now that's stupid as electric kettles use much less el
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"Lonely stretches of motorway" are not lit at night in the UK.
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You want to save electricity? Ban clothes dryers, electric heaters, dishwashers and electric kettles. At least you'd cost less lives than this insanity.
Actually, dishwashers usually use less energy and less water than washing up by hand, if you run them with a full load. And it's quite common in the UK to have electric hobs in the kitchen; boiling water in an electric kettle is always more energy efficient than boiling it in a conventional kettle on an electric hob.
Furthermore, the examples you provide are unambiguously uses of the energy to do something useful. Using huge amounts of power to light a completely deserted stretch of road at 3 am in the morni
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I always wondered if libertarians would have us all drive offroad rigs over mud trails to get around.
Now I know.
Would the exact opposite be better? (Score:2, Insightful)
I always felt that lights were less necessary when the highways are illuminated by all of the cars on the road.
Re:Would the exact opposite be better? (Score:4, Insightful)
Actually, there is a little truth to each.
Here in Australia, where we have hundreds of thousands of miles of roads (not looked it up, but wouldn't be surprised if that was fact) our interstate (read 1000-4000 km raods) are only lit up at places of interest, sch as turn offs or areas approaching a city or town. Our country roads are generally not lit up unless they incur heavy use.
When there are no lights, the road itself does seem brighter as you turn on your high beams and the reflectors point that light right back into your field of view. Now normally, you can easily see a car approaching with high beams on before you see the car (there is a haze around the next bend or above the crest of a hill) and both cars politely lower to normal headlights. However, if the other car doesn't lower his headlights in time, you can quite easily be blinded for a moment when struck by the full intensity of the high beams.
On raods that are lit up on the other hand, drivers less frequently use their high beams, so there isn't the potential to be blinded for a few seconds, but at the same time visibility isn't nearly as good.
In my opinion, having a safer road system is all about improving drivers rather than giving or not giving illumination on the roads. The best lighting on a road can't save you from a bad driver coming the opposite way - and by the same token, a total lack of lights doesn't kill people. I personally prefer less lights to encourage high beam use, but only if the other cars are alert enough to lower them if needed. To that point, to even get your learners permit here, you need to be able to answer correctly what to do if an oncoming car has high beams on (answer is look down and away to the road marking on the outside of the road which allows you to keep your car on the road and blinds you the least as your eyes are as far as possible away from the oncoming headlights while still keeping your car safely on your side of the road).
Light pollution (Score:5, Insightful)
if this makes for less light pollution then even better.
now if we can get warehouses to shut off their lights at night even better - security my ass - have they not heard of IR / lowlight video cameras - that would help even more...
Light deters crime (Score:2)
while an IR / low light video camera would do the trick of recording the crime well lighted areas deter it. A lot of criminals are stupid, but even the dumbest do not tend to do things in well lit areas.
Plus not all warehouses are closed at night, there is always the safety of the people who work there, including security people.
Re:Light deters crime (Score:4, Insightful)
The deterring argument has been proven wrong..... In a dark area, a burglar needs to use a flashlight that is likely to get noticed. In a well lit area, you're even providing him with illumination for his deeds.
You need movement sensors and someone who notices the lights going on and check accordingly.
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In a dark area, a burglar needs to use a flashlight that is likely to get noticed.
Why, do crims have particularly bad eyesight? Most of the time it's easy enough to get around at night with ambient light. And even in a particularly remote area where there isn't much of that, plenty of nights have moonlight.
Hoping that it's dark enough to require a flashlight seems like the worst security policy I've ever heard.
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Hoping that it's dark enough to require a flashlight seems like the worst security policy I've ever heard.
Compared with hoping the burglar is afraid of lamps?
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Criminals are a cowardly, superstitious lot.
Remember, every all concealing shadow could contain a Batman.
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Compared with hoping the burglar is afraid of lamps?
Yes. It's about a thousand times worse than that.
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Even ignoring that, a motion sensor is a better solution. Saves energy and reduces light pollution, has the security advantages of visible light (bystanders could see burglars) and draws attention to movement better than a flashlight, and better than the changeless always on/nightvision solutions.
Re:Light deters crime (Score:4, Funny)
You know what would deter crime? Sentry guns.
Electricity consumption -- where does it go? (Score:2)
Re:Electricity consumption -- where does it go? (Score:5, Interesting)
Nuclear power platns don't have that, but coal and water plants do. And as you're not actually surprised by reduced energy consumption at night, reducing their output is feasable within a few hours. For the small, unexpected movements you have gas plants that can be turned on within a few seconds.
On the other hand, the street lights in populated areas (not highway lights, we don't have them here) are indeed used for load shedding of nuclear power plants. (Worked in a town with one until two years ago. saw the streetlights on at day quite a few times)
Re:Electricity consumption -- where does it go? (Score:5, Interesting)
Re:Electricity consumption -- where does it go? (Score:4, Informative)
You are incorrect. Nuclear power can load follow perfectly fine. The reason why they don't is because the cost of nuclear power is almost entirely fixed in personnel and equipment. The fuel is practically free (and with fixed schedule refueling outages, whatever you don't use goes to waste anyway). Therefore running at anything besides full power 24x7 is a economically inefficient. In contrast with say, natural gas turbines, where nearly all of the cost is fuel so you only use those to make up the difference in demand.
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That's a lot of ifs. Maybe it would go in a storage pool which would have been become economic with lots of almost free energy at night?
Re:Electricity consumption -- where does it go? (Score:5, Informative)
The same place all the other excess energy goes into - methods to try and store it and use it at slightly less efficiency later in the day.
The usual example is to pump water back up a reservoir that's being used for electricity generation. So when it falls down again tomorrow, you can get useful energy from it again at the right time and only lose a percentage of the energy to keep pumping it back up there until you need it.
Still doesn't mean it's efficient but the thing about electricity planning is that they KNOW when things are going to ramp up or slow down (even down to the timing of the adverts in the middle of big football matches!) and if they know, they can do their best to compensate.
More likely, if the motorways are switched off on a regular basis, they will power down a more flexible station during those times because they know they won't have to supply as high a peak. You can't "turn off" nuclear easily, but the infrastructure isn't all nuclear. You could easily keep them going all the time to supply the "base" current and deal with peaks and spikes (like the motorway lights being on) with other means and get to shut down OTHER types of station that you wouldn't normally be able to because of the demand required.
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Unfortunately, the opportunities for pumped hydro storage, like hydroelectricity in general, are pretty small in Britain [decc.gov.uk].
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Electric cars? Some form of energy storage?
Ok, the next obvious answer then... (Score:4, Funny)
Why not just turn them off if there's no cars? Ok, current lights I'm sure take time to warm up, but if switch to these new lowpower thingies, aren't they near instantaneous?
Or....
Glow in the dark paint on road sides.
As cars travel by with their lights on, it'll 'charge up' and provide a clear path for the next car! Just one or 2 lights where needed at junctions (and as a heads up that there IS a junction up ahead), and catseyes/glowinthedark paint everywhere else! Save a fortune, increase road safety!
Or solar panel charged LED lights for road edges like you get at garden centres. Power up in the day, gently glow at night.
Ok, next plan...
Glow cars. Seeing as body panels these days are plastic anyway, why not make them slightly translucent, and attach lights inside the panels to make the main car itself glow? You'd be able to see cars far easier, dim headlights, giving cyclists/motorbikes clearer visibility (same brightness on their lights).
As cars brake, not just their rear brake lights, but the whole car illuminates/changes colour.
All in the name of saving power.
(posting so I've something to refer back to for prior art one day).
Re:Ok, the next obvious answer then... (Score:4, Insightful)
"Glow in the dark paint on road sides."
Never heard of cat's eyes? Simpler, cheaper, non-polluting and basically last forever (the UK ones spring down when you run over them and "clean themselves" in the pool of water that collects in a chamber underneath them). That's why all UK motorways and major roads have them already.
If we wanted to save extreme amounts of power, we could turn off all streetlights quite easily. Motorways wouldn't suffer, nor would back streets and most rural roads are unlit anyway. That's what headlights were FOR.
The point is to balance safety with power. It's SAFER to have lights on on the motorway but, if necessary, you don't compromise safety by adjusting them in varying levels of traffic. Still the road that you pull off the motorway and do 30mph in might be unlit, but that's a much slower road so it's much less of a risk.
It would be incredibly dangerous to remove cat's eyes or make them power-reliant. That's why they are there. Even a city-wide power-cut wouldn't stop us using the roads and motorways. But if we can switch off the MEGAWATTS of power that hundreds of miles of motorway uses when there's one or two cars per minute (try using even the M25 in the very early hours of the morning), that's an acceptable trade-off.
Translation (Score:2)
Never heard of cat's eyes?
As an aid to international understanding, I note that in the U.S. these are called Botts' dots [wikipedia.org].
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No they're not. They do mark out lanes and road edges, but they are a completely different principle. They use glass beads with mirrored backs to reflect light back at the driver. Like a actual cat's eyes do.
http://en.wikipedia.org/wiki/Cat's_eye_(road) [wikipedia.org]
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Maybe where you live, but where I live, we have reflectors buried in the pavement with metal to protect them from snow plows [wikipedia.org]. (I've never heard the term "Botts' dots")
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Unfortunately, recessed reflectors are SHIT to drive on. They are bad for the driver in every way. Here's why:
1. They are less visible at odd angles than projecting Botts' Dots (they are named after their inventor.)
2. The recesses trap grit and rocks which are kicked up when someone drives over them, either lane changing or lane losing.
3. The recesses pull the driver TOWARDS the line, while the projections pushed the driver AWAY from the line.
4. Water can collect in the recesses and turn into ice. There is
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"Never heard of cat's eyes?"
Aye, mentioned in the post, but that's on the ground/where your lights are roughly currently aimed as they need to bounce back the light a bit. Glow in the dark paint would illuminate where the lights aren't yet reaching.
The cats eyes will show you that the road is starting to turn left/right, the glow in the dark paint will show it's snaking back and there's a junction on the bend.
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Cat's eyes work for the distance your headlights reach, for curves and junctions (the colour of them changes for different road features - red, and green for the two sides, yellow for junctions, etc.). Decent headlights reach further than your braking distance at your car's legal top speed in those conditions (further if you "undip" them).
Anything beyond that is basically invisible anyway. If your headlights can't pick up a cat's eye in the distance (whether around a bend or not), it's because it's just n
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Name three road users
1) Cars
2) Um...
Well done. You've failed your driving test.
If you'd have said cyclists and pedestrians, you would have passed.
Don't forget about other road users. They often make the most mess.
Why not traffic signals, too? (Score:4, Interesting)
In the US in the 1930s it was common for major cities to turn off traffic signals in the middle of the night, also to save money on electricity costs. The criminal element quickly learned to use these times for their getaways, since they could cross town quickly without attracting the notice one gets when running red lights (cf. The Valachi Papers [wikipedia.org]).
I know there are few traffic signals on A roads but, as this is the UK, I can't decide whether "in for a penny, in for a pound" or "penny wise, pound foolish" is the more appropriate idiom.
EU Ratification (Score:5, Informative)
The biggest problem is that LED (CREE etc) based streetlights have not yet been ratified by the EU and so cannot be used on public highways in the UK. If they do become ratified then there will be huge power savings. In China, they have whole motorways lit up using this technology. Not only do they burn less power, but the lantern lifetime is much longer than the standard sodium units that have a warranty lifespan of 3 to 5 years.
One of the problems about dimming lanterns is that the lamp post spacing is all based around the lamps at a certain luminenscence and so dimming may create dark zones, or over bright zones. So some careful analysis will be needed about how the lamps dim and whether they dim uniformly or not.
Re:EU Ratification (Score:5, Informative)
The biggest problem is that LED (CREE etc) based streetlights have not yet been ratified by the EU and so cannot be used on public highways in the UK. If they do become ratified then there will be huge power savings. In China, they have whole motorways lit up using this technology. Not only do they burn less power, but the lantern lifetime is much longer than the standard sodium units that have a warranty lifespan of 3 to 5 years.
Actually, the power saving for road lighting are negligible at best, or negative at worst. Low pressure sodium lamps currently in use produce up to 200 lm/W, compared to 100 lm/W for the better white LEDs around. There's not much that can compete with LPS for pure lighting efficiency, partly because the light emitted is near the maximum sensitivity of the human eye. Of course, LPS lamps produce monochromatic light which means they're not so popular for lighting urban/pedestrian areas, as people feel safer in a more "natural" light where they can see colours. But for roads alone, there's no need to see colours. Also, LPS is the least objectionable form of light pollution to astronomers, as being monochromatic it's easy to filter out (and there's not a lot of glowing sodium in space, so you're not blocking out anything of interest).
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Strange, Philips is already doing massive installations in Europe. Contrary to what you apparently believe the EU does not have to sign off on everything member states do. Most of the "regulations" that come from Europe are actually just an acknowledgement of existing standards in member states, that tended to converge naturally anyway because of the advantages of doing so in the free market.
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One of the problems about dimming lanterns is that the lamp post spacing is all based around the lamps at a certain luminenscence and so dimming may create dark zones, or over bright zones. So some careful analysis will be needed about how the lamps dim and whether they dim uniformly or not.
I can personally verify this zone problem happens with at least some LED lights. I live in a city that has been testing old fashioned LED lights (a couple years, maybe a decade behind China at least) and they're trying to retrofit the LED heads onto existing poles but the heads they chose do not output the same light cones as the old sodium vapor or whatever lamps. So we get bright and dark bands flickering as we drive. I am not epileptic but I know the flashing sets them off and its bad enough to be dis
Tradeoff (Score:2)
Of course, the control system required is far more complicated here. I wonder how much energy is consumed in producing and maintaining the new lampposts, controls, communication network, etc.
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Most of the maintenance now is replacing lamps. If this is done alongside replacing with LED units, maintenance will reduce enormously.
And there's no need for new lampposts. Just make the new tech light fittings fit in the old lamp posts. Communication is hardly difficult or expensive these days.
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Of course, the control system required is far more complicated here. I wonder how much energy is consumed in producing and maintaining the new lampposts, controls, communication network, etc.
I put on my engineers estimating hat and...
I will call 1 KW per lamp. Yes its probably beneath but not much.
Cost per KWh is below 10 cents/KWh for everybody, far below for a major account like my city or the highway dept, but its "In the ballpark" when you add in corruption, management, accounting, overhead in general. So 1 KW lamp costs $0.10 per hour
yearly average is 12 hours per day of lamp and 365 days per year but thats a pain to multiply so we'll call it 10 hours a day and 333.333 or a 1/3 of a thou
Actual savings? (Score:3)
I'm sure the lights were not designed to be turned on and off as often as they would be under this scheme. It would be interesting to see how much money is actually saved over time, once the increased wear on the lights due to the frequent on-and-off cycling is considered. How many more light replacements per year will now be required?
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What frequent on-and-off cycling? They're talking on at dusk, dim when it gets quiet at night. Bright again for the morning traffic and off again when the sun's up.
Only the single dim stage is new.
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LEDs are used to cycling at 120 hz, or I guess 100 Hz in soccer-hooligan-land. This might be an excellent excuse to upgrade to LEDs.
Does anyone in the biz know what they use to drive the LEDs? I'm assuming a simple bridge rectifier and some manner of constant current switcher, but "real genuine streetlights" might do something more exotic, I donno.
Note I'm not interested in how model railroader or RC car builders bias a LED using a simple resistor, I'm quite well informed on that, thanks, I'm looking for
Nigel's lamps dim at 11 (Score:2)
They're one later.
Dazzle (Score:4, Insightful)
Ordinarily I would not care about the street lights, but these days there are cars with VERY powerful headlights, probably Xeon etc. and they look like someone has left their main/high beam on, dazzling oncoming traffic. And there are drivers that insist every day is foggy and the front and rear fog light dazzles you. And then there are the drivers with one headlight working, not bothering to fix the other one making it hard to guestimate how wide they actually are.
At least with street lights, it helps to lessen the contrast between the lights and darkness, and helps you see how close you are to on coming traffic. The UK has some pretty small roads, not the kind of wide roads the US have (if you look at Google Earth).
Night vision (Score:3)
Personally, I find my normal night vision + my headlights + tail lights of other cars is more than adequate to drive safetly at 70mph on a motorway or main road.
I find that (unless its an obvious danger spot) occasional lit stretches of road probably cause more danger than help as it takes maybe 30 seconds to get your night vision back to full capability after passing through them.
If they want to make motorways safer at night, then they should do more to reduce the effects of eye fatigue caused by repetitive momentary blinding from headlights of oncoming traffic.I suggest more natural light-blockers between the roads, such as planting hedges.
Re:Cue in big brother (Score:4, Insightful)
"Hello lamppost,. What cha knowing?. I've come to watch your flowers growing.. Ain't cha got no rhymes for me?. Doot-in' doo-doo,. Feelin' groovy.."
gets a completly new meaning then...
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"Hello lamppost,. What cha knowing?. I've come to watch your stored recording.. Ain't cha got no bombs for me?. Doot-in' doo-doo,. Packin' Semtex.."
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Actually I only want road lights when there is just enough traffic that I have to turn off the high beam most of the time. When there is very little traffic or the road is very busy, it's best to keep them off.
Complete straw man (Score:3)