A call to improve London's lighting at night
ianvisits.co.uk
ianvisits.co.uk
I get that they’re cheaper to operate, but they throw shadows differently and have more blue wavelengths in them (in nyc they’re 4000 kelvin last I looked). It personally feels much less magical to me and 3-4 years in I still haven’t really gotten used to it.
It also makes me feel less safe at night. I get that the orange glow makes everything look muddy, color-wise, but it doesn't kill your night vision to the same extent as the bright white LEDs do. Sure, things directly under the streetlight are lit up like it's daytime, but I can't see for @$#% in between the streetlights or behind the bushes or whatever.
I'm curious why it seems that no city has tried installing amber LEDs in an effort to try and realize the efficiency gains without quite so many of the downsides.
Flagstaff, Arizona did. There are some drawbacks, mostly that they simply don't get as bright.
https://arstechnica.com/science/2019/10/how-flagstaff-arizon...
“If you absolutely must use white LEDs, you could do what Tucson has done,” Hall said. “They... switched out their whole high-pressure sodium system to 3,000 degree white but reduced their lumen budget for street lighting from 480 million to, like, 170 million [lumens] or something. And you need to do that. For every white LED lumen, you're increasing your skyglow by a factor of about three, but they cut the lumen budget by about a factor of three. So overall, they managed to wash out the skyglow because they’ve got a lot of observatories down there.”
The extra blue is probably screwing up the circadian rhythms of humans and animals:
* https://www.health.harvard.edu/staying-healthy/blue-light-ha...
* https://www.npr.org/sections/thetwo-way/2016/06/21/482936520...
Efficiency regulations for residential fluorescent lighting delayed adoption by probably 25 years. Because regulations mandated lamps with terrible CRI.
The ideal for road safety would be more uniform lighting from a larger number of closer-spaced lamps, placed at lower height, diffused, shielded from the sides, and colored orange (and optionally uniformly dimmer).
It would also help road safety to ban the new bluer types of car headlamps, which cause much worse glare than previous yellower ones.
The color has almost nothing to do with that. Newer headlights are much brighter, and mostly use projectors now. The increase in glare is mostly due to the projectors, because they emit all their light from small point. You'll notice that newer cars with halogen projectors are almost as bad as one with HIDs.
It would be interesting to see how a headlight would look if it were able to emit the same amount of light on the road but from a rectangle spanning the entire front of the car. Minimum glare, still effective.
The color makes much of the difference. (What really matters is the total intensity in the shorter-wavelength part of the spectrum, so sure, making the lamps much brighter and less diffused is also bad.)
Shorter wavelengths cause significantly more glare, because the peripheral part of the human retina is packed with rods and S cones. Intense light including shorter wavelengths also causes the eyes to become bright-adapted, making it harder to see in the dark.
The super-bright halogen headlamps emit much more blue light than previous incandescent headlamps, and are included alongside LED headlamps in my complaint here.
Bigger, much dimmer, more diffuse lamps would help, but they should also be less blue. (And people should stop mounting headlamps on their SUVs and pickup trucks at other drivers' eye level and aiming them straight ahead.)
I have an LED desk lamp with a temperature setting, and when it's on the warmer settings it really does produce a pleasant light.
Here’s a cutsheet for a Lithonia wall pack fixture showing the different options, there’s also a chart showing what the lumens per watt is based on the color temp: https://img.acuitybrands.com/public-assets/catalog/1008038/w...
"Tunable" LEDs are just multiple LEDs, the goal being to change the emission peak. Peak wavelength can be mapped onto a black body temperature trough Wien's law (λpeak =2.8e-3/T) https://en.wikipedia.org/wiki/Wien%27s_displacement_law
I don't really know how the mapping is done, though, as there are different ways to map it since the LEDs won't have the same emission curve as a black body.
The night time lighting humans(and our non-human co-inhabitants of earth) have evolved with and known for a very longtime comes from fires of various types, flames with a much warmer color temperature.
Also, intensity is orthogonal to color temperature.
Consider the spread of lactose tolerance, a recent (no more than 10,000 years and perhaps less) mutation which has spread to 35% of humanity in that time. We have had plenty of time to co-evolve with fire, and doubtless, we have done so.
Its probably to do with cooked food, not vision - which is already co-evolved with the Sun, for when we are active/hunting/etc.
Wild animals very much do not. It's likely that our mucus membranes have also adjusted to the presence of more smoke: this doesn't prevent cancer, which is a post-reproductive problem for the most part, but it does keep smoke inhalation from being immediately debilitating.
Does it mean that fire doesn't fool our circadian rhythm into thinking it's still daytime? Sure, why wouldn't it? We've had a very long time to adjust, and getting appropriate amounts of sleep increases fitness in an obvious way.
We haven't had more than a hundred years of adjusting to bright blue-wavelength light after dark, however. So it could affect our circadian rhythm, and as studies show, it does.
My city has a contact on the web, you identify the light and what you would like shaded, and they come around and block the light on that sector. In my case it looks like they painted a section of the diffuser black.
White light reminds me of: dentist clinics, hospitals, metro stations... not very friendly places.
There's research about e.g. subway incidents and safety when they got better / brighter / whiter lights.
https://la.curbed.com/2014/2/3/10156584/las-new-led-streetli...
No affiliation, and no idea if there's truth to any of the marketing copy, but I'm personally very happy with them especially when driving at night due to the awful intensity of LED brake/tail lights on other cars.
Improving the lighting is also at odds with wanting a dark sky for the local wildlife too. It has a noted effect on birds for instance.
Apropos of nothing... I also remember a story about a northern country replacing traffic lights with LEDs and then spending even more money adding heaters because the old lights were naturally warm, and melted any ice that stuck to the lights. Can't find a link to it at the moment.
The Technology Connections channel on YouTube has an excellent video on this, called 'The LED Traffic Light and the Danger of "But Sometimes!"': https://www.youtube.com/watch?v=GiYO1TObNz8
I think partially the problem is people(us) have designed their lighting and safety around the street lights being on, and now they are not it is an issue. I have lived in other countries where the norm is for houses to have subtle outside lights that are permanently on at night. But around here they do not and people are more paranoid so all the terraced houses instead have over-active motion sensors with massive flood lights. That are now very noticeable when a poor late night clubber/shift worker/early morning dog walker/baker etc walks by...
I think it is neither "natural" or better illuminating. Sodium lamps have CRI of around, what, 30?
I'm glad that these sodium lamps are finally getting replaced everywhere, and cities at night won't have that monochromatic depressing-ugly-yellow lighting.
Sure what you outline is possible in some spesific scenario, but it's not gonna work for 99%
With LEDs it should be very possible to light streets with low temperature close-to-blackbody light. (I don't know if the proximity to a blackbody radiation distribution is the same as CRI etc.) Who wouldn't want this?
There are two ways of doing “white” with LEDs:
• Separate red, green, and blue, whose spectrum is spiky: https://en.wikipedia.org/wiki/Light-emitting_diode#/media/Fi...
• Phosphor, which may give you a spectrum like this: https://en.wikipedia.org/wiki/Light-emitting_diode#/media/Fi...
My home city has metro coaches with either yellow or white lights. Me and a few friends of mine would skip the white ones because we found the yellow ones more comforting. On the other hand, my dad prefers white and in a room with types of lighting he will always go for the white ones.
it would be neat to have light strips alongside the sidewalk and the road, as well as above. that way, the light can be lower intensity in aggregate while still providing the necessary illumination (via surrounding light vs. flooding) to make out details. our eyes are highly adaptive, and we don't need a lot of light, but rather, light from many angles.
also, the safety argument is often overstated in relation to the intensity of light. you only need a little light to reduce crime and accidents to its threshold. more isn't better in this regard.
It lit the street and not everything else.
I could see a few stars in the night sky, for the first time since moving to London.
I no longer had to deal so carefully with light leaking into my bedroom.
The primary effect is that its like having a near full moon effect at all times of the night. Not looking directly at the light reveals a landscape that is not harsh on the eyes but never catch a lamp straight on.
Fortunately around me the birds caught on pretty quick at first singing at odd hours until they sorted it out.
Overall its a benefit as it has opened up hours people can walk the sidewalks and even in the street without worrying about wildlife blundering into them
I've recently encountered a couple of construction sites which are illumunated by a particularly pleasant green hue at night. That might be even better.
And while we're on the subject of street lights, can we please stop with all the light pollution?
A daylight colored bulbs are probably not doing our night vision any favors (but then head lights have the same problem, yes?). Going from a lit street onto a side street with few lights is potentially a problem depending on the kind of street lights.
More importantly, colour temperature >3200K screw up the circadian rhythms of humans and animals:
* https://www.darksky.org/our-work/lighting/lighting-for-indus...
* https://spectrum.ieee.org/green-tech/conservation/led-street...
Light with more white in it feels brighter.
Drivers prefer whiter headlights because it feels like the road is more illuminated.
Car manufacturers move to HID or LED projectors for whiter light.
Whiter light causes the pupil to contract significantly more.
Drivers with contracted pupils from the white headlights find the yellow sodium bulbs in streetlights and parking lots too dim.
Governments and businesses replace the sodium bulbs with bright white LEDs.
At every step along the way we're seeing less of the night. Shadows become darker. A person or animal coming in from the shadowed roadside is increasingly invisible. A mugger can jump you from an alley with no chance of being seen because the shadows are so deep.
Now we have to increase the portion of the Earth that's illuminated at night for "safety". This disrupts animals more and deepens the shadows further.
It's incredibly stupid and there's no way to stop it without some overarching power a) doing a scientific study into night lighting and b) using that as a reason to impose intense lighting regulations and enforcement.
Too late now.
> A notable characteristic of the village is its almost complete absence of street lighting. Villagers have consistently voted against the installation of such lighting for decades, fearing that it would damage the traditional village ambience and require a rise in council tax. Only the approach to the tube station features a small number of lampposts.
The claim, in favor of such widespread lighting, is that it makes something "safer", but the evidence seems weak on that:
https://www.washingtonpost.com/news/wonk/wp/2017/11/02/what-...
All a bit too Panopticon for me.
1. https://urbanlabs.uchicago.edu/attachments/e95d751f7d91d0bcf...
https://www.ucl.ac.uk/bartlett/research/impact-bartlett/impa... In the UK in 2005, there were 8.12 million lighting points on the country’s streets using approximately 3.14 TWh of electricity, meaning CO2 emissions of 1.32 megatons. 6.31 million of these lighting points were streetlights.
Bartlett research found that lower levels of brightness are required for white streetlights than for yellow sodium vapour lights. Switching led to energy savings of 30–40%.
I would guess they're white just because white LED's are now the cheapest colour, and whichever company was paid to do a study was given criteria to ensure they came out looking best. The study probably also took manufacturers claims of "100,000 hours lifespan" at face value, despite the fact half of them in my street have failed in under 2 years, which should have been detected in a small scale trial first...
At least they don't PWM flash...
The benefits far outweigh the problems and it's one the of the more minor changes we are going to have to make to the way we live if we re going to have any hope of curtailing climate change.
Surely this position is not absolute? Indeed, the most effective way to eliminate human-induced climate change is to, well, eliminate those causing it.
In your view, can any attempt to curtail climate change be justified? I'm genuinely curious and mean no disrespect, should you feel such.
That'a actually a really interesting question. Clearly there are quite a few "finally solutions" I would put entirely off-limits - mass slaughter, compulsory sterilisation or contraceptives. Outlawing meat? Nope.
But I think there's quite a few possibilities between 'lets kill people' at the one end of the spectrum and 'lets change the light bulbs in public street lighting, even if it's a bit harsh' at the other.
Now we get birds doing their morning call at 2/3/4am.
There are always trade offs. Is safety for those who must commute late at night a fair trade off for lights that are less pleasant on the eyes?
Somebody needs to drag the local politicians/town council to Home Depot (or the UK equivalent) and show them the warm-white vs bright-white vs other consumer LED bulbs. And if they still choose the bright-white, fire them/vote them out.
Also meanwhile, cars are getting super bright headlights that actually make it harder to see at night in the city (signs and windows will reflect a lot more than people, you'll be blinded by oncoming cars...)
My point being, there is no safety tradeoff being evaluated - we're getting super bright, super white LEDs because of economics (white/cool LEDs are cheaper) and a general fascination/desire to get the brightest thing possible.
Any sources for that? I always read that the only times bright (LED) lights blind oncoming traffic is when they are improperly installed aftermarket.
At night, nearly every vehicle I come across produced > ~2018 has blinding headlights that require me to squint drastically.
I can see the light’s blinding reflections in other cars’ rear view mirrors at night when a higher vehicle is behind them.
As a side note, the crazy lights are bad for pedestrians as well: they're so bright you sometimes have to look away from incoming traffic (esp. if there's a hill involved, tilting the vehicles) and they make it harder to estimate distances (all you see are the lights, which you can't look at, and not the vehicle they're attached to).
Are you referring to people that commute by car or in general? I don't generally have a problem with very bright lights on a highway, but do we really need them on residential streets? I didn't feel unsafe taking subways and walking at 3-4 am in NYC pre-LEDs. In fact I much preferred it, the city felt dreamier (for whatever subjective measure of "dreamier" is, of course).
In general.
Because you didnt feel unsafe it does not mean that you were unsafe and that other didnt feel unsafe.
I agree that the yellow lights look nicer in general.
Probably the most unsafe I've felt in the city was a random fight between passenger's on the subway in mid-day when the guy I was standing next to flashed a gun. Probably should have moved away from him now that I'm thinking back on it, for some reason I just kept standing there -- NYC sort of trains you to just accept wild situations I guess. Except if the person starts taking off their pants, then you definitely have to move to the next car.
If folks are that concerned about their safety at night time then they shouldn't live in London. London is not a safe city and never will be, no matter what part of it folks live in. That's part of the London-ness of living in London tbh.
I'd vote to keep the non-white lights. Adds to the duttiness. London needs more dutty after the oligarchs took over central and general gentrification silliness.
There is a lot of research into the effects of light on sleep quality and it's bad. I have to put significant effort into blocking out street lights in my bedroom which means using blackout curtains even in winter. It's also bad for birds and other wildlife which rely on lighting to determine the time of day. I used to live on a street which turned the lights off completely at about midnight and it was so much better.
I echo globular-toast's complaints because I have a bright LED street lamp right outside my window which prevents me from sleeping unless I close my curtains, meaning I can't wake up to natural light in the morning.
Street lighting is excessive and unnecessary and unless there's a study that says otherwise, I doubt it has any impact on crime.
Yes, I am bitter. A decision like that should be backed by evidence that it will actually improve something.
That's one of the most significant differences between most parts of most British cities, and many other European cities.
I doubt it will change, since it would require laying new wires and (probably) getting permissions from building owners, but I think the absence of street light poles makes a street look much nicer. (But without a pole to lean the bags against, where would Londoners leave their refuse on bin day?)
Even better than building-mounted lights are lights suspended from wires strung between buildings, as in Copenhagen [1] (that is unusually heavy rain, the photographer was "lucky").
I live in Malmo and they have the same way of mounting lights for the streets in the inner city.
https://www.electronicsweekly.com/news/products/led/red-led-...
> for actually doing anything it just doesn't provide enough light to see
It sounds from your comment like red light is good enough for collision avoidance. Why else would light be needed from street lights? We all carry phones with flashlights nowadays.
In other words: little or no evidence. Just some people have a fear of the dark and others find that the indiscriminate lighting of streets disturbs their repose and relaxation.
In classic deuteranomaly the red and green cone peak sensitivities are closer together so red and green light are perceived similarly.
The red cones aren't gone and in low light you aren't even using your cones, you're using your more sensitive rods. Rods are inherently color-blind in all of us.
What is useful about a red light is that it has very little blue. Blue light is what causes the iris to contract.
So the ideal night lighting would be a brightish mix of red and green to give the rods lots of light to see with almost no blue in it to stimulate the blue cones and cause the eyes to contract...
Oh hey! That's what the yellow color of sodium lighting does if there aren't a bunch of stupid SUVs with bright white projector lamps all over the road.
Fancy that.
I’m sure the real answer is [less bright LEDs and force the community to adapt to dimmer night lighting] but, you know, safety
Same as most government decisions. Some combination of "it was cheaper" and "I don't live there, it's for the plebs".
Boris Johnson, Tony Blair, Jeremy Corbyn, Emily Thornberry, Margaret Hodge …
• Corbyn has been an MP for Islington South since 1983
• Thornberry is MP for Islington North since 2005
• Margaret Hodge was on Islington council for 21 years
So I would say it's somewhat unfair to accuse it of being a stereotypical choice for them. They live(d) amongst their electorate.
When it comes to street lights, there's an argument to be made that you do want to interfere with/defer the sleep of anyone who's walking/driving outside.
The problem of course is collateral damage to people's houses where street lighting leaks into their windows, but assuming this is mitigated, I think street lighting that intentionally defers sleepiness is better.
White LED street lamp makes the road super clear, but messes up your night vision. You don’t see the pedestrian about to step in the road, then you hit them. Could have been averted with warmer, orange lights.
Of course, while I was looking that up I found out he made a video about sodium vapour lights! <https://www.youtube.com/watch?v=wIC-iGDTU40>
Unless there is solid evidence they should not be withholding lighting.
Some folks want to drink outdoors or chillin the park, and they will with or eithout light, but like this a lot more people will break their nose or leg
So sad for Sarah's family and friends!