I'm concerned by the fact that this response to blue LEDs, while founded on reasonable sounding theory theory, doesn't seem to have much high quality, real-world data AFAIK (e.g. insomnia in houses with blue LEDs vs not, comparisons between people using the glasses mentioned vs not, average bedtimes of people correlated with tv usage, any studies looking for causal links in day to day life, etc). Such studies might exist, but I don't think I've seen or heard them referenced, just mentions of how blue light decreases measured meletonin or what not in clinical settings. Mostly I just hear anecdotes from people who have fully bought into the line that this is a serious problem that requires time and money thrown at it about how awesome their life is now that they've gone out of their way to reduce blue light exposure, opening them right up to the placebo effect.
I'm double concerned since the answer for this seems to be "buy more stuff" and "blindly assume blue == bad without followup research or verification". This is one of those situations where it's pretty easy for companies to swoop in and offer at-best ineffective and at-worst actively harmful products to solve a problem that might or might not exist.
Also, just because you personally aren't aware a body of research exists doesn't mean that there isn't a sizable and increasing body of it. "It didn't randomly cross my radar..." isn't a deeply compelling foundation for doubt, especially when a few moments of web searching could have opened the door.
Free for now with the future hope they will make money. So it's free but with the same incentives as any early company that launches for free to grow the user base.
Given we already know it disrupts melatonin (as well as noctural wildlife), this feels like one of those cases where the burden of proof is on the proponents, before we roll out millions or billions of dollars of LED streetlights around the country.
You know who really stands to benefit the most? The companies that get to sell us blue equipment, and then next sell us replacement blue-filtered equipment when we prove night time blue light is a problem.
The cities that have already installed 5000K or 6500K (aka "daylight") lamps will be the natural experiments.
You're kind of proving OP's point. You're just spouting off "facts" with no real understanding behind what exactly was said. What exactly did the study say? We've seen more than enough examples on HN about studies whose premise and conclusion have been mistranslated so many times, who's to say this isn't another case of it?
Exposure to blue light suppresses melatonin levels. Melatonin is previously understood to regulate sleep. Ergo, while causation between blue light exposure and sleep quality is not proven, we at least have grounds for suspicion.
What understanding am I missing? What "facts" are being misused?
What understanding am I missing? What "facts" are being misused?
Jumping in from the sidelines, when you say "Exposure to blue light suppresses melatonin levels", I think the main thing missing is a notion of "dose response". How much blue light causes how much change in melatonin, and how does this affect sleep compared to other factors?
Others here in the thread are suggesting that a blue LED indicators on electronics are a travesty. While I hate LED's of any color in my bedroom at night, and tape over indicator lights of all colors, I'm doubtful that this level of exposure affects melatonin levels. Does you think it does?
An interesting point from both of them is that in controlled studies, both melatonin supplements and blue light exposure seem to cause about a 10 minute difference in time to fall asleep. While real, this is a much smaller effect than I would have guessed from most of the popular press coverage.
Although, care must be taken, as many nominally warm LED's still have a huge amount of blue emissions. For example every Philips colored LED bulb, including red and orange, have a big spike of blue. The only exception is the yellow bulb, which is sold as a bug bulb... In other words, the engineers only chose to control the blue emissions in the one bulb; everything else is default full of blue.
Same thoughts exactly, I have a LED lamp which allows me to adjust the color, all the way down to a dark red (insanely warm) glow, in which it’s hard to red certain printed texts. Not sure when LED became blue light only?
LEDs put out a lot of blue because most of them are based on phosphorescence, and high energy light (blue or ultraviolet) is required to drive the phosphors. It's possible to make a white LED without phosphors by combining different colored LEDs, but they're not as bright and much more expensive. That's also how you make them color adjustable.
High quality data is nice, but at some point one has to get on with one's own life, rather than wait for data. I bought a pair of glasses to filter out blue light on the advice of my dad (who has an eye problem and was recommended them by his doctor) and it has made a real difference - I can now do a full day's coding in front of my LED screen without feeling like my eyes went up against a cheese grater. YMMV
We do have the trouble of identifying it. Apparently"good" products isn't harmful because they are well made and doesn't emit the dangerous frequencies.
Add to that consumers nowadays often have the ability to turn off the "color enhancing" modes that phones and TVs ship with.
And further the LED lamps nowadays can also produce the warm coloured light now when we now how to make them cheaply without turning to "crank up the blue until it looks acceptable".
It seems to me (please correct me!) that this an old issue. "Unfortunately" LEDs last a long time so there are plenty bad LEDs out there, but as long as you buy reputable brand LEDs it seems this is a passing issue.
This time around it seems that manufacturers are well ahead or consumers and now when we are starting to realize it has already been fixed.
Especially since one of the recommended solutions is buying $79 glasses which don't seem to be much better than the ones that Home Depot sells for a fraction of the price.
In fact, I've found the cheap ones are better - I got a pair for £20 off of Amazon and found them to work better for me than the £79 pair of Gunnars I had.
This was my takeaway as well. As indicated by the very first comment on the article, the author seems to be completely unfamiliar with the concept of colour temperature, yet still happily pushes LEDs == "blue" light == bad.
All in all an interesting but uninformed article (which seems par for the course on Medium these days).
Almost separately from the circadian-rhythm concerns from the article, a major design peeve of mine are random products that have unnecessarily blinding blue LEDs. Worst example I know of: an otherwise competently executed automatic HDMI switch with several incredibly bright blue LEDs, always on. So bright as to be able to read and see all objects in the same room. So when you might dim the lights to watch something? The switch is still blinding blue, usually right at the viewers!
I mitigated this by disassembling the switch and installing some 3-stop ND (neutral density) lighting gel to dim these stupid LEDs to acceptable levels. This product at least afforded a good-looking solution -- many can't be disassembled to fix the problem.
I've been ranting about Blinding Blue LEDs for years. It seems that, almost as soon as blue LEDs became available, Every. Damn. Manufacturer. decided, "This is the new style because, hey, blue LEDs!"
A blue LED isn't so bad if they tone the brightness down, but too many companies can't be bothered, or just think it's "cool" and "edgy."
I've heard of people applying a thin layer of black nail polish over eye-blasters like those. Fortunately, my main system's case has a door that normally stays closed, mercifully hiding the room-lighting power indicator.
> an otherwise competently executed automatic HDMI switch with several incredibly bright blue LEDs, always on
Oh my god I had one of those. I put several layers of opaque tape on them and I could still see the damn LEDs through. I'd rather say that in jest but I still suffer from retinal persistence just by talking about it (seriously, barely kidding). I don't even know how such an insane device made it through any form of certification.
I have a tv that has an led to display that it is off. LED is obnoxiously over used for displaying things no one gives a shit about. But personally my pet peeve is the annoying beeping everything does. It doesn't provide any context or useful information. I've been at a self checkout and have the clerk turn it back on after I muted it while scanning items. It resets after the transaction anyways. Everything has beeps or bright LEDs.
Phones are my biggest complaint - not mine as all sounds have been turned off, but everyone else’s. You get a sound when you receive a message, when you unlock it, when you type a message and when you send a message. It’s just so pointless and annoying.
My personal worst example is my Rabbit Air HEPA filter. This device is very likely to be used in a bedroom at night, especially in spring - and yet it has an always-on display of bright green and blue LEDs. I've had to completely cover the display with electrical tape.
Yeah, we've got a humidifier like that, useful in wintertime but with a crazy-bright LED numeric display and several different colors of lit buttons. Christmas trees aren't as bright as this stupid thing.
On the other hand, a HUGE shout-out to iHome's line of smartphone-saavy alarm clocks. The big snooze bar also acts as a multi-level dimmer, with complete 100% OFF as one of the levels. These have started to become popular in hotels, meaning I'm no longer That Guy who unplugs the alarm clock, stuffs it under pillows, etc.
LEDs just got more and more efficient. Even driving them with tiny currents produces bright light nowadays. I suspect once the efficiency increases stop, manufacturers will adapt and their engineers settle on limiting resistor values that are actually appropriate.
So... there's these great things called data sheets, and they tell you how much current to run through your LED to yield a specific brightness level. Then you throw it into this bad boy here for instance [1]. You still have to do this to validate your design for every part picked.
It's like saying CPUs are getting more efficient, you know, so let's just run way too much voltage through them and hope for the best, and when the industry runs out of efficiency gains we can revisit it. Sure it's hotter than the devils nutsack. It'll be fine.
Efficiency gains are totally irrelevant to this conversation. It's designers who didn't read their data sheets, didn't care, or only tested their product in bright light. No excuse.
For an example datasheet check out [2], the luminous intensity vs. forward current graph is on page 7.
As a Red/Green color blind person I LOVE blue leds. They have mostly replaced the stupid Red/Green off/on indicator that I can't tell the difference between.
Now if only stop lights changed to "blue means go" we would live in a sane world. Picking two colors to mean opposite things (in life and death situations) that 5% of men can't tell the difference between is just a bit silly.
A simple solution for traffic lights would be to change the shape of stop lights to an octagon (matching the stop sign). This would be easy now they aren't a single bulb.
Could also change the amber light to a triangle.
Emergency, Fire and Police flashers are mostly blue by convention. Fire, not as much, unless volunteer.
Beyond that, I've always found green lights to be fundamentally, much brighter than any red lights. Tail lights and traffic lights don't shine through bedroom windows nearly as much as when traffic lights turn green. You can see the same effect in black and white photography, but then again, not all traffic systems are the same intensity.
I have a high powered LED flashlight, with a red low-light option, and I find the red LED nearly unusable. I think red, though, is usually a dimmer color than green, when it comes to lighting in the additive color model, and lighting elements.
It's reflective colors that present much less distinguishable differences.
I've noticed that myself (especially if there's a gas station nearby with a green-LED price sign). The green traffic light is, at least to my eyes, noticeably blue-green/aquamarine, where the gas station sign is emerald green.
PWM resources can be quite scarce or overkill for a constant brightness level, just pick the right current limiting resistor, it's embedded design 101. Heck, it's your first-year electrical engineering class.
It's not hard to PWM by hand; it takes next to no resources.
Current limiting resistors don't really do great at lower strength; LEDs have far from linear responses and it's very constrained at the lower end that you want.
Source: wrote embedded firmware for close to a decade.
which another large chunk of manufacturers messes up by choosing to low a frequency and not adding a filter, so now you see the flicker as soon as your eyes move...
I put a few layers of blue painter's tape over it. Works great. That way, you can still see the blinking indicators, but the intensity of the light is greatly diminished.
And you can peel it off, years later, without any sticky residue either.
I'm surprised it worked for you. I have an Asus N66W router with 5 blindingly bright blue LEDs. Being in my bedroom, it made it really hard to sleep.
Placing three layers of electrical tape didn't work, the light still passed, although significantly dimmed, through the tape. Also, because the router's case is thin plastic, most of the light leakage was through the case. The only solution was to put a pillow over the entire thing. But in the morning the router had overheated and didn't work until resetting it.
Nowadays I just unplug the router before going to sleep. It's driving me insane.
Although it's not an issue as it lives in a cupboard, my ASUS RT-AC68U has a switch on the back which completely disables all of the LEDs. Also to their credit, even though the LEDs are blue, they're not of the obnoxiously bright variety.
Already posted in another comment, but these "LightDims" stickers work perfectly for me. They also have different colors to blend in with various cases: http://a.co/7KaPIM2
No affiliation, just recommend them to everyone when I have the chance!
Beaglebone Blacks have annoyingly bright blue LEDs, but I find that a double layer of Kapton tape (a thin, translucent amber plastic tape used in the electronics industry) dims them to an acceptable level.
My town recently replaced the dull, orange-ish street lights in my neighborhood with very bright, white LEDs.
The street is now very well-lit, but I share the author's concerns and experience with this kind of light creating an environment that's not conducive to sleep, or to unwinding in general. When I look at the new street lights I feel like they were taken out of a hospital operating room.
Another thing I noticed when the new lights first went in was that the birds started chirping at all hours of the night. I don't know if they were always doing that and I only noticed after the new street lights were installed, but it makes sense that the light would have a similar impact on animals as it does on humans.
I wonder if anyone else noticed this when the lights in their neighborhood were upgraded to these harsh, white LEDs.
One of the streets I drive on regularly is the dividing line between two towns, and it actually has the new LED bulbs on one side and the older bulbs on the other. Even without the one malfunctioning LED assembly that's strobing, the difference is pretty jarring and rather disturbing. I'd much rather have the older bulbs back, or at least something closer to them in appearance.
I'm not the only one to notice the difference either - I generally have my phone mounted to my driver's-side vent and on with a map, and when I'm driving on the "old bulb" side of the street with the new bulbs shining from behind on the phone, it's much brighter - presumably its light sensor is perceiving the LEDs as being much closer to daylight.
There are companies making non flat non white LED lamps these days. They try to emulate the feel and color of filament bulbs but with LED films for power savings. I don't know if they improve things though.
They don’t necessarily have the same spectrum. Not an expert, but my conclusion from the little I looked into this is that lighting is hard. And decision makers don’t seem to consider externalities.
The Sodium Lamps normally used in Street Lighting have a very very narrow colorband (their color index is basically 0, if you look at something under sodium light, it's colorless other than the sodium yellow).
LEDs can be more easily adjusted and can have a wider color band plus you can use multiple modules and change color as needed (blue light in early evening when rush traffic is on and then going into narrowband sodium yellow for the night). It's a question of power delivery and PCB complexity that limits what you can do (controlling a high powered 50W LED isn't trivial)
Amber lights are conducive to sleep since blue wavelength light messes with circadian rhythms so they might be useful on stretches of roadway that feature long-haul driving and late-night traffic like larger thorough fares but I think they have a very deleterious effect on animals and plants.
One of the things I love about the suburban neighborhood I live in is how dark it is at night (relatively speaking, not like being in a true night-time darkness in the wilderness).
I live in a neighborhood where many people leave 5-6000K security lights on all night. It boggles my mind. Any possible health effects aside, I just find non-natural light in that spectrum to be really unpleasant to look at. The temperature of the security and street lights really kills an otherwise pleasant neighborhood vibe at night.
You can't change blue light to another color with a filter. The amber light has to be in the spectrum emitted by the lights to begin with. The filter just isolates it.
That's overly simplistic - you can use phosphors (and similar chemicals) to change the color of the light. The phosphors absorb light and emit light of different colors. Many daylight bulbs do this.
There's an interesting Wired article, about how teams at Philips struggled to come up with the optimum filter. IIRC, at some point they were using some type of gel to 'tint' the LED light to resemble an incandescent bulb.
Of course, nearly all of this has probably flown out the window, because the bulbs are so cheap now. (The Wired article was from over a decade ago.)
That was the article about the Switch bulbs if I remember correctly. I think the company went out of business. I have a couple of them and they work and look good, but are really heavy and I can't use them in certain applications that were only ever meant to hold up really light incandescents.
After realizing the effect that blue light had on my sleep I went on a crusade to eliminate it from my life after sundown.
I used red LED bike lights for room illumination until I found a series of alternatives. The cheap, remote-controllable 5 meter multicolor LED strips are an amazing solution to evening lighting. It is also possible to get "warmer" LED bulbs. These are often marketed as looking like antiquated filament bulbs. But the best solution is pure red light.
I also removed every single blue-LED backlit computing device from my life. I've made sure to use OLED phones since they were first available. I finally have an OLED laptop, and thankfully, as they are no longer being made! The change in laptop screen really is the most transformative thing for me, as I often need to work in the evenings. I set all the backgrounds in the OS to black, and use browser plugins to set the background of the web to black as well. I have never slept better since blue LEDs came into my life.
People really need to take this issue seriously. There is evidence that blue light's disruption of circadian rhythms and suppression of melatonin production is related to cancer and other health risks. Blue should be reserved for the color of the sky, which is where our bodies evolved to recognize it directly as the input to our circadian rhythms.
I am pleased by the wave of "night light" filters for phones. This is a sign that people are catching on. They use the filters and feel able to get to sleep. We need to go further. OLED everywhere and deep night mode for all.
Using pure red light for the night is a good idea, since it doesn't decrease our eye's ability to see in darkness. That's why it is used in submarines too (if the electricity is cut, night vision of the eye is already fully functional).
A bit more detail: the rods in our eyes responsible for night vision need ~45 mins of darkness for full adaptation (though some night vision is achieved after a few minutes already). Light disrupts this adaptation - but not red light! So with only red light on, both the night-vision rods and the red-sensitive cones are active the same time.
Flux and night shift modes only reduce blue light, but they don't eliminate it, unless you have an OLED display. Backlights on LCD have tons of blue light that can't be reduced without a physical filter.
Ubuntu 18.04 has a night mode built into the gnome shell. It works really well, allowing a complete removal of blue.
But neither of these has any point if you have blue light bleeding through from the LED backlight of the LCD screen. The most complete solution is OLED and a screen temperature adjustment like this.
I feel like Apple really dropped the ball on that. Neither of the two reverse video modes remove blue. Flux works great on OSX and the people that make it really care about low-light accessibility, I'm typing this on my Dark Mode MacBook that I bought specifically to live at my bedside. Nothing else compares.
iPhone's accessibility page for color filters looks like a clown car show of useless features. If anyone's found the magic configuration that makes that shitshow usable please share it.
1. You can set "reduce white point" to reduce white light
2. You can set a color tint filter and move the hue far to the left. That's the red/orange area. Set intensity to max.
3. You can set the accessibility shortcut to turn these on. (This one is lacking - it slows app switching on non-X devices)
I don't know how to assess actual colour spectrum output, mind you. Does this seem effective?
I think the problem I had with this one is that any time you're looking at something that would be white, instead it's super bright red. Without something that actually changes the displayed colors, you're stuck reducing the contrast so much everything's barely legible. But I'll give it another shot, thanks.
For personal red illumination I use USB-rechargeable NightRider rear bike lights. I ultimately got two and I take them everywhere with me. They are great night lights, especially when travelling, except for the fact they flash blue when you turn them off to indicate their charge level! Using bike lights makes sense as they are designed to be durable, waterproof, and long lived.
I've used a series of OLED screened phones. Rooting can help to ensure you really can put a full screen temperature adjustment on the phone. I regret not having done this on my current phone, which is a oneplus model.
In the past year or two a huge number of multicolor LED lighting solutions [1] have shown up on amazon. These are usually cheap strips of several hundred multicolor LEDs, and come with an IR remote that lets you set one of a number of colors--- among which are pure rend and oranges that are nice in the evening.
It's no worse than on a phone. I've never noticed burn in on any OLED phone or my current laptop (although the latter is newer).
I'm using a thinkpad X1 yoga OLED. The biggest danger with this device is using Windows, as the drivers for the display panel have a bug in them that will lead to degradation and destruction of the panel. Using Linux avoids this issue.
I think she has a good point about how too much blue light might not be very good for us. There has been interesting research in this are.
It's true that traditional street lights (sodium vapor lamps[1]) are warmer, but they also provide more limited light spectrum (only one frequency of yellow) for this reason they are mainly used where the price and power efficiency outweighs the limited visibilty. So it's not strange that given the option to get better color rendering at a good price, LED technology using full spectrum light has been prefferd.
However, there's nothing stopping us from using LED lights with warmer spectrum, and that argument is probably good to raise. With the higher control of the spectrum that LED gives us compared to the previous street lights we might even be able to create a good compromise using warmer but still wider spectrum lights.
My house's front door faces a street lamp, and ever since the town replaced it with a white LED, it's terribly blinding to walk by in the evening. I wish my door came with flux or nightshift.
That being said, I wonder how much of this is marketing the wrong product. When I see towns or cities advertising the shift, they use phrases like "more natural lighting" (yes, cool white is closer to daylight) and "brighter" (a messy concept when including colors, but I think they mean perceived brightness which again goes back to cool daylight temperature).
Those sound like Good Things for a city (which I imagine is why they're buying these things), but really we're being marketed the wrong things. I don't want "more natural" daylight lighting at night, because it's night and I want to sleep. It may make drivers slightly more alert, but it comes at the cost of polluting everyone else's house (like my front door).
So the people being marketed these lights hear things that sound good and sound like they make our communities safe, but really these are features we don't actually want for nighttime lighting... we need to realize we need different solutions for this problem.
> for this reason they are mainly used where the price and power efficiency outweighs the limited visibilty
I always thought these lamps were inefficient, which is why they are being replaced with LEDs, but apparently they output up to 200 lumens per Watt which is better than most household LEDs.
Do any LEDs match the spectrum of those sodium vapor lamp? The ones I looked at had a higher blue profile even if the output colour matched the yellow.
In fact, yes. The illumination spectrum of sodium vapor lamps is very specific -- they emit almost all of their light around 589nm (amber) [1]. You could easily replace the light from a sodium vapor lamp with an LED lamp outfitted with LEDs manufactured to emit that particular frequency of light.
The LEDs themselves are not particularly expensive either. Linked a digikey page with a potential part you could use.[2]
I highly suggest installing f.lux[1] on your computer and using a similar app on your phone like Twilight[2]. They've done absolute wonders for my sleep schedule and I actually feel noticeably sleepier as the night goes on when using them. And occasionally when I do turn them off (when working late at night), I feel more awake and alert which was an unexpected plus for when I'm under crunch but an unwanted side effect when I'm trying to get a good night's rest.
What I don't like about the night light built into W10 is that there is no gradual change in color temperature between day and night. I use redshift on Linux and it lives as a KDE Plasma applet sitting in the system tray: it knows when sun up and sun down are based on my lat / long, and it gradually changes the color temperature accordingly. Really sweet.
What colour temperature are you domestic lighting bulbs?
Mine are 6500K, as are many in new developments in my area. Under such simulated daylight, changing screen temperature just makes it look muddy and malfunctional.
F.lux and its ilk are also counter-productive for anyone working with colour, like designers or photographers.
Obviously reducing blue light from screens is not going to be helpful in spaces lit by blue light. 6500k bulbs are not suitable for night time lighting.
The US has banned[1] the (previously) standard low temperature (~2500k) incandescent light bulbs that have a black body radiation profile. Lots of low frequency. I really prefer these at night and could not find replacements. Eventually someone suggested that the key words are "rugged service". That and "incandescent light bulb" will get you many options on amazon, ebay, etc. Not sure if I need to stock up on these or if they will continue to be available into the future.
There are plenty of LEDs available with a 2700K color temperature. It helps to buy ones with 90+ CRI, although few (even the good ones) actually advertise their CRI on the label. Last time I bought bulbs, Home Depot was selling 80 and 90 CRI bulbs under the same freaking model number; it's like the WRT54G all over again.
Granted, it's not a true black body spectrum because the infrared part is missing, but that's why they use less energy.
It is too bad that manufactures are not required to put a spectral analysis graph on the packaging of these non-blackbody light sources. Not sure how they even calculate a temperature rating when the blue and red frequencies are the highest with yellow and green quite low.
> The US has banned[1] the (previously) standard low temperature (~2500k) incandescent light bulbs
Not true. They established minimum efficiency rules. Old 60W bulbs can meet the rules but 100W cannot. You can still buy 60W incandescent bulbs everywhere.
If a 60 watt bulb lasts 1000 hours at $0.10/kWh, that's $6 even if the bulb was free. So quadrupling the price has negligible effect on its total cost ($6.25 vs $7.00).
The skeptic in you would be pleased to know those "post-ban" bulbs fail much faster, and live about a quarter of the time.
As much as I tried to avoid all of these new ugly light bulbs (never met a florescent that looked right, and it took me a long time to find an acceptable LED), I eventually just got rid of all incandescents and got CREE warm whites.
Maybe I'm more radical, but I wonder why we need such constant, brilliant illumination anyway?
I know I'm an outlier but I often don't turn lights on, or only turn on task lighting, and at night outdoors I usually use moonlight when and where I can, or a dimmable flashlight if that's not sufficient.
If you drive, the lack of street illumination makes it harder (even with your lights on, of course). And driving high beam is not a solution because that’ll blind incoming drivers
I am used to driving in rural areas that don't have street lamps, so I'm probably not the one to consult on that kind of thing, but I don't find that streetlamps do a tremendous amount.
It's strange how the switch to LED lights feels rushed and often not thought through all the way.
Last winter, several intersections around my city had problems with snow accumulating and blocking the stop lights, because the new LED bulbs don't generate enough heat to melt the snow that accumulates. I guess hindsight is always 20/20, but it's surprising the people paid to make those decisions didn't think of it beforehand.
The snow-melting effects of incandescents seems like something that was always there and "just worked" and, therefore, required no though. I'm not sure "the people paid to make those decisions" think it through any more than any of us can take the time to consider every possible consequence of every decision we make every day. And us tech folk already could be accused of overanalyzing many things, while still missing a ton..
Agreed. But these decisions are being made by (and I must admit here I know nothing about the subject matter at hand, this is just speculation) almost certainly tens of thousands of municipalities across the country, independently. From small towns to big cities. From huge, organized departments that attend traffic signaling conferences, to folks who treat this component of their job as almost an afterthought. And we're only noticing the towns that screwed up, not the one that wisely chose NOT to implement LEDs for these reasons. Or the ones that made the calculated choice that, based on snowfall patters in their region, energy savings, savings on maintenance costs, vs the higher purchase price of the LEDs, that the LEDs were probably the right choice.
Honestly because the switch to LEDs has been at least as much about virtue signaling as any real savings. The energy savings will eventually pay for the LED conversion, but it takes a while. As in years. And as to unintended side effects, well we're just discovering those.
Payback time on domestic LED bulbs is actually surprisingly quick. We have "100W" LED bulbs that draw around 11W of power, and cost ~$5 each, compared with say $1 for a 100W incandescent light bulb. At 20c/kWh that's 20kWh of electricity, or ~225 hours of run time at 89W of saved power. Even if we only ran a bulb for 3 hours a night, it would pay for itself in two and a half months.
I imagine the case for street lighting is even stronger, especially when you start to factor labour costs for bulb replacement as well. And traffic lights would be stronger again, because they're cycling instead of being constantly on, which shortens the filament life significantly.
Where's your numbers for that? My local muni operates about 10,000 street lights. If HPS averages 400W apiece, that's 4 megawatts, run for maybe 10 hours a day, at $0.10/kWh that's $4,000 a night...
Now if by "years" you meant "two years", then fine, I can believe it- but two years is still a fantastic payoff period.
Don't forget HPS burns out pretty regularly too. Tactic my muni is using is simply to replace burnt-out HPS with LED instead of repairing it. Lo, after a few years we're probably half LED.
The entire problem they're talking about is high color temperature, not LEDs. No need to spread FUD with titles & writing like this - I have lit my home with pleasing warm white LEDs for years and they've paid for themselves in energy savings.
I am surprised there is not much noise over this. In my city, they recently replaced street lights with the LED ones. These were so bright and piercing, I complained to the city, and they replaced ones near my house to lower intensity one. Still the other one's not the nearest to my house are still so bright, it is very unpleasant, even though they are at a distance. No one in my neighborhood seems to be bothered by these? In my opinion these pose serious risk to health, not just ours but to birds, animals and plants. Even when driving on roads, where these lights are on, they just hit you like a sunlight.
Washington, DC is starting to switch to LEDs for streetlights. They're whiter than the old sodium bulbs, but the District uses 3000K lights for main streets and 2700K for residential streets. The LEDs are directed towards the ground at a 45° angle--the globe diffuses the light, but they produce much less light pollution and they'll save a ton of power, time, and money.
The youtube channel Technology Connections has a couple of interesting articles about LED (and sodium-vapor lamp) bulbs in street lighting: https://www.youtube.com/watch?v=wIC-iGDTU40
(Actually, most if his videos are pretty interesting to explore, especially the ones about early TV)
Something I've realized recently is how over lit our homes can be. Like most homes, mine have always had a bunch of lights I didn't really choose with simple on/off switches. But I'm remodeling my house now and have been testing different led lights and smart lighting systems, and in the process have discovered how much better the lights are when they're dimmed!
Setting aside the blue light issue for a moment, I wonder how much a simple reduction in lumens would be helpful. Just putting our lights on a smart dimmer solution (noon home for the curious) has made a big difference. I rarely turn the dimmers above 50% and it's plenty of light with a lot less glare and using even less electricity than having leds on standard switches.
With the remodeled part of the house the lights will all be LED, but 2700k and every one of them will be on a dimmer switch.
The complain is really less about Blue LEDs and more about high temperature white LEDs (5000K and upwards). Those really fuck up the circadian rythm.
A warm or natural white LED is much less harmful (3500K and under and 4000K respectively) and you can mix both. Only a few days ago I found a very interesting LED module that would mix both and use the natural white for full light intensity and mix over to the warm LED when you dim it via PWM or DC going as low as 2000K.
Myself, I built a LED RGBW controller and I use the Red and Blue channels to change the color temperature of the strip itself. The strips can be had for very cheap on chinese websites, individual LED modules with WS2812 pins cost less than a dozen cent. High powered LEDs of various temperature don't cost that much either.
"Because red, green and blue LEDs are required to make white LED light"
Just to nitpick a bit: you only need blue LEDs to make white LED lights. Most modern white LEDs use a phosphor coating (the yellow you see in the LED chip) to get white light out of the blue LED.
Are there cities trying to have zero lights at night ?
Sometimes I wonder how it feels to have no light at all. There's a calming aspect to this, my mind really feels that 'no sun = no activity'. But also a little bit of fear too, unless everybody is already home.
I used to commute a lot from San Diego to Portland, and the blackness of Portland was jarring. San Diego has way more lights, but it also lacks cloud cover, so the light looks different.
I'm not sure the light profile of LED streetlights are sufficiently different enough from Mercury Vapor lighting for anyone to really notice a difference - both have significant emissions in the blue spectrum, and we used MV lighting for 40 years.
Are mercury vapor lamps actually widely used now, or for the past decades? I thought the most common lighting type before LEDs were sodium lamps which are most definitely not blue.
"We can’t easily call for our cities to go back to a less intense light. The switch has already been made, and cash-strapped cities need the savings."
Yes we can, and we should. Where does this learned helplessness come from? Cities are always cash-strapped. "It'll cost extra," should not be some trump card to shut down discussion of doing something that is provably better for the populace. There should standards devised for the idea color temperature and brightness of street lighting, and government should be required to stick to them.
Many TVs have a light sensor and will dim the display in a dark room. It saves energy and probably makes the brightness more appropriate to the surroundings. (It doesn't adjust the color temperature as far as I know, just the brightness.)
I'd check your settings. On my Samsung, it's under System -> Eco Solution -> Eco Sensor ("Automatically optimizes TV screen brightness in response to the room lighting.")
The whole point of the LED was that the white color provides better vision at lower luminosity. If you make it yellow, there's no advantage over sodium vapor lamps which are already very efficient.
They would still have a much broader spectrum. Sodium vapor lights are very unnatural [0] — I certainly wouldn't describe them as "cozy" and "more human", as the author does. Plus, the low-pressure ones are difficult to distinguish from a yellow traffic light.
This seems like a good way to save both sleep & energy while preserving a good visibility. According to the page, the CRI (color rendition index) of their warm LEDs is better than conventional HPS lamps. This means that you can actually distinguish objects better with it.
I have also heard of someone who patented a filter for LED lamps, but I don't know how far he got with that. In my city, we have some of these filtered LEDs installed and it feels more pleasant than any white/blue LED streetlights I've seen.
My HOA is currently researching LED lights for our parking structures. These are the best high-intensity not-blue (3000K) candidates we've found so far:
I always found it ironic that the controls on my CPAP machine have bright blue back-lighting - and no obvious way to adjust it. It would light up the whole bedroom if I didn't put an old hand towel over it.
OTOH, our clock-radio has a nice, warm and dim orange display.
Maybe I am barking up a completely wrong tree, but this seems to me more than anything else a shameless ad for the "healthe" filters and "Truedark" sleephacking glasses.
My 1985 Volkswagen Golf had a blue LED for the high-beam indicator. I've always wondered how they were able to afford those long before conventional wisdom said they were cheap enough.
Every hardware store we go to here (Thailand) has LED lights (in all forms - flood lights, 'tubes', screw-in globes, even the flexible strip-lighting for hidden lighting) in at least two and usually three 'temperatures'. From most to least 'blue', they are "Daylight", "Cool White" and "Warm White". No price difference.
So, is this whole article basically just a rant because nobody this guy knows ever buys "warm white" bulbs?
I'm double concerned since the answer for this seems to be "buy more stuff" and "blindly assume blue == bad without followup research or verification". This is one of those situations where it's pretty easy for companies to swoop in and offer at-best ineffective and at-worst actively harmful products to solve a problem that might or might not exist.