Even more informtion on LED streetlights.
What does a regular streetlight look like?
Here's a cobrahead, they come in a variety of styles/variations.
Why should I care about this?
You should care because they are replacing working fixtures, many of them are decades old!
Another reason you should care is that many of the old lights get thrown away, and then sent to a landfill or then recycled.
Aren't LED streetlights more efficient than the old ones?
This is technically true, but there's more to the story. To get a higher efficiency, they have to use "lens panel" optics, which I think is bad for streetlighting. It can cause more glare and has worse light control than the older lights.
Non-LED streetlights have a bulb in an optical compartment which has a reflector and sometimes a "refractor" too. To aim the light, fine variations in the reflector direct the light to where
it should be. But with LED, even though these "lens panel" optics appear to work well enough, it is inherently limited in its capabilities. Also, if you're
skeptical, check out Optics.
But aren't they eco-friendly?
Only theoretically! In practice LED lights are worse than what they are replacing,
and that's due to the complex circuitry and the LEDs themselves. It takes a lot of energy (and materials) to make an LED streetlight.
I like white light!
I like white light too, but from personal experience, I can say that the color of white LEDs
is a downgrade compared to other white-light sources such as metal halide. The comes from LED's simplistic spectrum, which consists of some blue lught mixed in with some
green-yellow phosphor. It's easy to see where it misses the mark in rendering colors, which is one of the main reasons white light is being used. The other problem with using white LEDs for streetlighting is that it creates a sense of boringness, as it's
just the same white light everywhere, with no variety. It's important to have some variation with lighting, or nighttime
will become more mundane without it. Unlike LED, HPS has slight variations between manufacturers and is (I think) more interesting. It's up to you to
think for yourself, so I'll stop with this relatively subjective section.
I'll do it later.
There isn't much time left! Get started now, or very soon, as a lot of fixtures have already been changed out.
You can also start by getting a non-LED yardlight and tell other people about it.
I want some scientific studies!
I can see why you want them. It's hard to trust a website without them, so here are some hand-picked scientific articles that show this situation in more detail.
Reduced effect of glare disability on
driving performance in patients with blue light–filtering intraocular lenses
This study shows how lower blue light can increase the safety margin when making turns when driving. At first, you may be wondering how this study fits in with my website. But if you think
about it, the people are experiencing lower blue light levels (because there are filters in their eyes) and this positive effect can be replicated with light sources with lower blue light levels.
Should vision influence roadway lighting design?
This article compares photopic and scotopic light levels. What I can see from this study is that even though LED works well in low-light situations, it
may be a little too good at this. For example, when a yardlight or streetlight is shining your window, you want that light to be non-disturbing. But if your vision
is scotopic, you can see details easier than if it were high-pressure-sodium (HPS). This ultimately means you're kept up at night, because all the details in your sleeping location are now visible
thus exciting your mind.
What about yardlights?
A lot of the info here applies to those too, such as not converting them to LED.
You can go to this page for that info, and then go here for a guide on yardlight maintenance.
Here are some words you can use to help stop LED streetlights:
Why LED is bad
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