LED streetlights, yes or no..?

[Funkybulb]

The only decent LED street i ever seen is in Walmart car park using GE evovles. They were using 1 KW pulse start
Cram MH lamps. Using 180 watt leds. Yes carpark is dim
But at least u could see. They took it too far down n wattages that led replace MH of 400 watts. far cry of 1KW MH .

Now rest of streetlights ive seen is garbage
Cant even Light main roads to see the curb
On the other side. Where SON street lighting
Did ok. As road was orginally designed for
MV street lighting.

The Best installs of SON lantern i ever seen is
Texas Department of Transport. Highways
As there were no dark spot between the lanterns

[Kev]

I've got a bit of debt Elaine like 30 grand lol but that's life

[Ash]

I would call BS even if the claim was 400W LED replaces 400W MH

The efficacy difference between LED and good MH is not great, it is not over 2 times difference (e.g. 180 vs 400) even in plain Lm/W. But besides Lm/W, we have the fact that MH Lm and LED Lm are not equal. MH spectrum covers what we see, while LEDs are tailored exactly for the tests but not for anything else. (this have nothing to do with CRI)

[Slyspark]

Can't say I'm surprised at all. It's the same with most LED fittings. You get asked to install a load of LED panels or something and suddenly the lighting level has halved. Despite the fact on paper, they're very similar. It's a massive con, designed to drive sales of an expensive product to make the manufacturers a ton of money. Sod actually saving the planet or saving you money, all they care about is their increasing profits.

[Zelandeth]

I'm no fan of the approach that LEDs are the answer to everything - but I have to admit that the lanterns they've just been installing in our area - while somewhat odd looking on the square columns here - are a vast step forward in terms of the light level and quality.

Here's the before photo from yesterday...

IMG_20180829_211808.jpg

...and the same bit of road as of about an hour ago.

IMG_20180831_213148.jpg

The dark patch between the parked cars is where one column hasn't had the lantern changed because the gear door couldn't be opened due to being overgrown with ivy. That alone shows how big a difference there is. Have to admit that seeing this much light from 26W lanterns (that were previously 70W) really surprised me. As for longevity...time will tell. At least these fittings are actually serviceable unlike quite a few.

I'm surprised to see the council putting Halophane V-Max lanterns in... usually it's the cheapest nonsense they can find around here.

The old globes (originally MBF, latterly SON) were very much part of the fabric of Milton Keynes, and I'm sorry to see them go. I can't deny though that the optical characteristics of the globes were far from ideal (having a tinted diffuser over a streetlight is never going to do the efficacy any favours!), and the power usage dropping from 70W to 26W apiece isn't to be sniffed at.

Problem is...this is one good example of LED kit...and there are so many more that are utter crap than decent!

[AngryHorse]

I have to admit now, there's no contest anymore with hid/led street lighting, led is just so much better.
After driving about in it for a while now, and seeing existing son installations, son now make the roads look dark and colourless!
Also I will have to get some night shots of the new Rubycon lanterns that Weaver Vale are putting up on mass here, the light output of these is stunning!, but very different from most led lanterns?

I can't find any mention of them on Lenas website though????, but they have some sort of, 'led bar' in them, (bit like Philips's Formento), that give a softer light with NO glare at all, but at the same time, evenly light the road at really high levels.

[Ash]

"Good" LED results are achieved when the HID installation they replaced was in very poor condition. Even slightly yellowed or dirty streetlight bowls block most of the light, the same effect would be achieved if the old installation would be replaced with anything else new from the box

All the more so when the HID being replaced used some inefficient optical design (whether very old and not advanced design, or where optics were traded for some fancy style of the luminaires)

Other than the "wow white light" factor, LED do not have advantage where SON is otherwise ok. The white light still does not allow as accurate color rendering as expected - things appear largely in color but slight shades are missing. (which is worse, as under white-looking light we do expect to see things as they are). Under SON lighting we use the available little color information together with completing the rest from our mind to see things correctly. E.g. trees look brown but we complete it to green, and are even able to tell accurately the shades of green

Additionally, cameras really don't do justice to SON - We see much better under SON in person than cameras represent in pictures

If we want White light, compare to PL-L instead. With PL-L in luminaires with good optics (like Dave's Altra), the road would be illuminated at least as well. Considering that the PL-L is likely less efficient in Lm/W than the LED, this means either :

- 24W PL-L providing lower light level, but that is more than made up for by the better light spectrum (giving better color information of the surroundings, not straining eyes even in a long walk outside), and no glare from the luminaires

- 36W PL-L providing about the same light level, with all the other advantages in place

[lasagafield]

Load of Halide and HPS near me.
One of the last strips of road that isn't fully LED.
Sodium and Halide all light up the road nicely but the LED is not only dimmer, once you get 15ft away from the post the road goes black.
Don't even get me started on the LED replacing the LPS on the smaller roads/estates.
Unless you're directly under the post you aren't going to appreciate the dim cold and ironically low-CRI light from these things!
Besides from that with the LED lights on corners it's hard to tell if someone else is driving round that corner.
Mate of mine lives on a corner he's always going up the wall about it.

[Kev]

Dunno what lanterns they are using in your area rich but the ones I have seen have been shite, Plymouth for example. Personally cosmo wins hands down against LED imo!

[Zelandeth]

The old lanterns here were never going to be the best. Relatively poor optical control and a diffuse *tinted* globe meant that they did a better job of lighting up the sides of buildings, hedges and the sky rather than the road. Originally being 125W MBF the actual lumen output wouldn't have been huge.

The photos I posted above have been exposure compensated to best match how it looks to the eye to account for SON usually looking dinner in photos. I realise the foreground is a bit mismatched, but the street in front of you is accurately rendered in terms of apparent brightness.

Could HID do as good a job? Yes it probably could. Would have meant complete wholesale replacement of the fittings anyway though, not just a clean and re-lamp. If doing that, I reckon they've done the best they can to try to future proof things. At least the V-Max are fully modular and serviceable, unlike a lot of LED fittings which are just a blob of potting compound and heatsink. Fact is that the lighting team will have been instructed by the powers that be to use LED kit most likely, whether they like it or not. At least they've tried to do it sensibly!

A friend of mine stays on the other side of town, where identical fittings to these went in about six months ago, and so far there has only been one failure - and that was because the whole column was knocked over in an RTA - that either of us has spotted in that area.

Fair bit better than when they installed LED kit on one of the main roads, and there were lanterns out all over the road before they had even finished the install!

I'll be curious to see how these stand up to the test of time.