
Energy Saved, Sleep Lost: The Unintended Consequences of LED Lighting - Kroeler
https://medium.com/@caseorganic/energy-saved-sleep-lost-the-unintended-consequences-of-led-lighting-c0909d4872d0
======
null000
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.

~~~
st26
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.

~~~
adrianN
We could still roll out billions of dollars of LED light but conservatively
choose LEDs with a warm spectrum. Yellow LEDs exist.

~~~
bamboozled
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?

Helps me sleep incredibly well and it’s an LED.

~~~
mark-r
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.

------
saidajigumi
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.

See also: Dyson rechargeable vacuum cleaners.

Maybe it's time for an LED shaming tumblr...

~~~
MrBuddyCasino
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.

~~~
monocasa
Or, you know, you can just PWM them rather than having them going at full
blast.

~~~
arcticbull
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.

~~~
monocasa
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.

~~~
arcticbull
Thanks for that! I'll keep that in mind. I'm largely self-taught in embedded.
Curious what you mean by PWM by hand.

~~~
monocasa
> Curious what you mean by PWM by hand.

Have a timer that is some function of your PWM frequency, and manually toggle
the GPIO line in the timer interrupt.

You can do it in a super loop too if you don't care about power consumption.

------
nchammas
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.

~~~
dannyw
It literally costs pennies to fix by using a film to get amber light.

~~~
ams6110
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.

~~~
maxerickson
A lot of "white" LEDs have a layer that absorbs some blue light and reemits it
at a longer wavelength, with the mix looking white:

[http://www.photonstartechnology.com/learn/how_leds_produce_w...](http://www.photonstartechnology.com/learn/how_leds_produce_white_light)

It's not a filter of course.

------
eggie
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.

~~~
codebje
Have a look at f.lux, which alters your display's colour temperature as the
time of day changes, shifting away from blues into the evening.

~~~
redisman
macOS and iOS also have Night Shift these days which is the same feature baked
in.

~~~
ekun
Windows also has had this for a little while. I don't know if it's a default
in Android.

~~~
Vendan
Modern android has a "night mode" that you can configure to turn on after a
certain time of day that cuts the blue light.

------
jonex
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.

[1] [https://en.wikipedia.org/wiki/Sodium-
vapor_lamp](https://en.wikipedia.org/wiki/Sodium-vapor_lamp)

~~~
graeme
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.

~~~
asteli
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]

1:[https://commons.wikimedia.org/wiki/File:Low-
pressure_sodium_...](https://commons.wikimedia.org/wiki/File:Low-
pressure_sodium_lamp_spectrum.svg)
2:[https://www.digikey.com/products/en?keywords=XPEBAM-L1-0000-...](https://www.digikey.com/products/en?keywords=XPEBAM-L1-0000-00601CT-
ND)

------
vichu
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.

[1] [https://justgetflux.com/](https://justgetflux.com/)

[2]
[https://play.google.com/store/apps/details?id=com.urbandroid...](https://play.google.com/store/apps/details?id=com.urbandroid.lux)

~~~
severine
Or the free alternatives f.lux inspired, Redshift[1] (for desktop) and Red
Moon[2] (for Android):

[1] [http://jonls.dk/redshift/](http://jonls.dk/redshift/)

[2]
[https://f-droid.org/en/packages/com.jmstudios.redmoon/](https://f-droid.org/en/packages/com.jmstudios.redmoon/)

~~~
19690401
Unfortunately twilight gets _much_ redder than these, and hence is much more
helpful to (my) sleep.

~~~
severine
> twilight gets _much_ redder than these

Any reference to that? I've used Twilight before, and didn't notice that when
moving to Red Moon.

Did you mean the default settings?

You have sliders for colour temperature, intensity and dim levels:
[https://raw.githubusercontent.com/LibreShift/red-
moon/master...](https://raw.githubusercontent.com/LibreShift/red-
moon/master/app/src/main/play/en-US/listing/phoneScreenshots/1.png)

You can create different profiles as well, plus limit brightness. I just
tested a very very red filter (lower colour temp, higher intensity level).

------
njarboe
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.

[1] [https://en.wikipedia.org/wiki/Phase-
out_of_incandescent_ligh...](https://en.wikipedia.org/wiki/Phase-
out_of_incandescent_light_bulbs#United_States)

~~~
p1mrx
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.

~~~
njarboe
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.

------
jaggederest
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.

~~~
dannyw
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

~~~
jaggederest
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.

~~~
copperx
That's not a problem if you have good eyesight. But some people can't see well
in the dark because common eye conditions such as nearsightedness.

~~~
jaggederest
I'm severely nearsighted so I'm not sure you're hitting the mark here :D

------
perilunar
Shout out to the International Dark Sky Association. They've been talking
about the problems of LED lighting for years.

[http://darksky.org/?s=LED+lighting](http://darksky.org/?s=LED+lighting)

~~~
smolder
But there's no problem with LEDs, there's a problem with high color
temperatures. Please stop conflating the two.

------
jlarocco
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.

~~~
ams6110
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.

~~~
taneq
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.

------
smolder
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.

------
sunjain
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.

~~~
jonstewart
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.

~~~
smolder
Nice to know not every municipality is too dumb to research color temp before
buying into a conversion.

------
news_to_me
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](https://www.youtube.com/watch?v=wIC-iGDTU40)

(Actually, most if his videos are pretty interesting to explore, especially
the ones about early TV)

------
sxates
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.

------
zaarn
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.

It's not a hard problem and definitely solvable.

------
audunw
"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.

------
agumonkey
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.

~~~
johnvanommen
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.

------
Aloha
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.

~~~
pilsetnieks
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.

~~~
Aloha
Mercury Vapor was widely used from the early 50's to the mid-70's/early 80's

------
stupidcar
"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.

------
DogOnTheWeb
I would love to see a night-mode solution for televisions, either via an HDMI
pass-through device or a film if necessary.

Do any products exist for that use case?

~~~
adrianmonk
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.")

------
TheSpiceIsLife
Does no one produce and high intensity 2700K LED light for street illumination
purposes?

It seems like this would be an obvious and easy solution.

~~~
scythe
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.

~~~
ScottBurson
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.

[0] [https://en.wikipedia.org/wiki/Sodium-
vapor_lamp](https://en.wikipedia.org/wiki/Sodium-vapor_lamp)

~~~
DenisM
I concur - I own a couple of 2300k LED lights and the light the give off is
very cozy, nothing like the streetlamp.

------
anotherevan
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.

~~~
copperx
My ResMed turns all of its lights off about 5 seconds after you turn it on. I
thank its designers every day.

------
jaclaz
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.

------
mark-r
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.

------
graeme
Has anyone tried the Health-e screen covers mentioned? I’m wondering how
effective they are and how easy they are to use.

I currently use reduce white point and color filters at night.

------
remir
I bought some anti blue-light glasses on Amazon and they really do make a
difference. 30 minutes after I put them on, I start yawning.

If I took them off the effect is jarring.

~~~
mkbkn
Could you share the link please? I see many options but not sure which ones
are right and which ones are knock-offs.

~~~
remir
I got this pair from Uvex:
[https://www.amazon.ca/gp/product/B000USRG90/ref=oh_aui_detai...](https://www.amazon.ca/gp/product/B000USRG90/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1)

What I like about them is they cover my entire field of view. They're not
really fashionable, but I only wear them inside anyway.

------
stephenr
I must be missing something here.

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?

~~~
smolder
Yes, most people don't even know what color temperature is, because they don't
change light bulbs - someone else does it.

------
JaggerFoo
Try living in Sweden, where people have been dealing with sleep and light for
a very very long time.

LED lighting is a pussy compared to the Sun

