LED lighting

It is the beam angle which causes this, nothing to do with colour temperature. Whilst some spill reduction is a good thing from the point of view of dark skies and efficiency, round here they have simply retrofitted existing lighting columns.

The resulting coverage does appear far more patchy, and since there is also less spill reaching property frontages, it feels a much darker environment if you are walking.

Chris

That's happened here in 'ampshire (SO21). It's good that the lights seem to have less upwards scatter and are more efficient but the overall result in our village is that it's very difficult to see parked cars and walkers on the road that runs through the centre. I'm not sure these new lights are entirely fit for purpose.

That was on TV the other night I don't think they factored in bulb/lamp prices . They didn;t include dimming either.

I wasn't asking about the cost of the LEDs.

I asked about how much leccy they would save.

Interesting that despite so many going on and on about energy saving lights they won't even guess at a figure.

Why guess what others can save given insufficient data about them?

There are substantial government grants available for councils and commercial users to replace lighting with LEDs, as part of an effort to reduce electricity consuption, and avoid rolling blackouts. Many councils have taken this up, as a way to get ageing lighting columns replaced, which they otherwise could not afford to do. Actually, I've seen many relatively recent HID installations being pulled out and replaced again with LEDs.

Mind you - replacement of the large LPS lamps with LEDs is probably a bogus electricity saving, as the LPS has a higher Lumens/Watt than LED streetlamps currently do. Replacement of LPS has been pushed by the lighting industry (because they make no money from them), and the government fell for it.

North Hampshire has just gone through a program of replacing all residential streetlamps with fluorescents, including remote switching and dimming, but I think that predates the recent government grants.

Someone has to buy them. if you''re going around replacing all yuor lights then that costs money, which is the reason I left mine blow through age and then replace them.

I'd like the tubes in my lab replaced with LED's but it seems they can't afford it. They can install LED under lighting in the roof garden and have them on where no one is , in our new graduate building.

They didnlt mentioned that just how mich monet could be saved.

Who was the they ?

Plenty will volunteer a guess about the percentage you'd save on your gas bill by changing to a condensing boiler. Without knowing the actual circumstances of that household. Like if it has gas fires, for example. Gas cooking.

So I'm curious just why no ballpark figure for changing from tungsten lighting to LED is also given?

It's just that I saw a figure on TV - as part of other figures given for saving energy. Insulation and so on.

Why?

No point when you know the percentage saving is substantial unless you are calculating how long it would take to pay for the new higher priced bulb. And few bother to do that for various reasons when the bulbs are so cheap even with the new more expensive version.

In Leicester, only the lamp heads were replaced. Now the programme is almost complete there is no longer an orange glow over the city at night. The streets seem to be as bright as they were before the change. And I can see constellations and stars from my front door that I couldn't see before, although it is not as dark as it would be in the countryside.

A village station near me has had platform light upgrades to LED - and rather cleverly, the lights run dim until you walk near one, then it fades up (not switches) to full brightness. A sort of inverse Supernatural mode...

To save the college money and every, every month I don't have to report that a number of tubes are flickering or have now stopped working. We brought 4 out of our teching budget as a test and they seem OK. We are about to have half our windows boarded up so it will be much darker in the lab.

Sounds like a good idea when I was in stockholm in the miod 8-0s they had e scualtors that didn;t start until you go close to them (maybe it was just l ate at night this happened) 10+ years ago you could select when the centra l line tube trains doors opened or not now the switches are still they but they no longer work.

Here its been head conversion to Concrete Utilities columns, in some areas the spacing is way too far and ends up with puddles of light and threatening shadows, opposite of what street light6ing is meant to achieve.

Never enough cash to do it right , always enough to screw it up a couple of times.

Only place left in western World making low pressure sodium is (mebbe was) Philips plant in Hamilton, used to have a nice Philips neon sign on outside, neon is starter gas in LPS lamps.

Astronomers are one group who don`t like LED streetlights, LPS emits on 2 very narrow bands close together, easy to put a notch filter on telescope and lose all the orange glow, not possible with white LED.

Do you get your fittings and tubes from the very cheapest on Ebay?

What makes you think cheap LEDs will last any longer?

Yup - got those on the local station too. A nice touch as the old lighting spilled everwhere. I'd guess those living nearby will appreciate it.

Original sodium was pretty narrow spectrum - but high pressure rather better. And that is a bit old hat - lots of lighting went HID, before LED.