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Comment by persnickety | Hacker News Reader

> But there is a downside to LEDs: They're much brighter than old-fashioned energy-guzzling light bulbs.

Are light bulbs actually being used in street lighting? I can't recall ever seeing that. Typically there's some gas-discharge lighting for that, and as far as I know, good old sodium-vapor lamps are pretty energy-efficient, on top of being not-terrible for astronomy.

This makes me wonder: what are LEDs replacing? And why are LEDs being installed rather than sodium-vapor lights? Is it because they are whiter? Cheaper to install? Just more hip?

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Cheaper to operate, which over an entire city's worth of street lamps is very material. Sodium-vapor lights eventually need to be replaced (as do LEDs), so why not replace them with a modern technology that's cheaper to operate?

Actually they aren't in terms of energy. High pressure sodium lamps output around 100 lumens per watt, which is the same as LEDs.

I'd imagine some LED luminaries are consuming more energy than the sodium lamp they replaced, as they are usually brighter and some will have terribly inefficient power supplies.

Common low pressure sodium and white LED street lights are about the same in efficiency: around 140 lm/W. LED street lighting pollutes the night sky with light that astronomers find impossible to fully compensate for, impacts wildlife (and probably not in a good way), inhibits low-light vision adaption in drivers and pedestrians, and gives public areas all the attractiveness of an operating theatre. All this for a dubious promise of savings after tens of millions of initial investment from each local authority.

>Cheaper to operate

I’ve seen in a number of places where the led lights have rapidly degraded, putting out really unpleasant bluish, purplish hues, as if the super bright daytime like sports field lighting everywhere wasn’t already bad enough. So this rapid degradation necessitating replacement no doubt eats into some of the cost savings.

Also, “cheaper to operate” mostly seems to have turned into “pump out more photons” instead banking the savings and maintaining nighttime lighting at non eyeball scorching levels.

There was some historical reporting where lights were delaminating because of a bad batch of panels produced by Acuity. It's not representative of the majority of LED installations, but each install may vary.

https://fee.org/articles/why-are-some-us-street-lights-turni...

Interesting thanks. It may not be representative of a majority but it seems pretty widespread, and it is representative of a type of problem led lights are prone to, at least right now.

I’ve had issues with household LEDs that needed replacing well before expected lifespan.

I also saw this article some time back discussing issues with LEDs. https://nymag.com/strategist/article/led-light-bulbs-investi...

I’m not against LEDs, but the usage and implementation in a lot of cases to date could be better.

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