Saving on LED lamps

[Andy Burns]

£1.50 vs £3.20 for a 13W LED equivalent

If you were running them for 8 hours a day, it saves 0.7kWh a day for the LED vs the incandescent, or 23p/day, so a payback period of under 8 days!

[Andy Burns]

My bathroom is pretty small (essentially a 6'6" cube) so a 470lm lamp is plenty, that costs just over 1p to leave on for 8 hours. If I need more light the mirror is illuminated.

[Chris B]

That was certainly a claimed response a few years (3 or 4) ago. Because LED lighting is so cheap (after purchase of the lamps) many more people now have house/garden floodlighting or decorative lighting than used to (It was confined to those who could afford the leccy).

Certainly seems to have some degree of credence round here with several bungalows with "downlighters in the eaves and front doors with always on floodlights - never used to be like that.

[zall]

That obviously depends on the price of the new one and how long the old one lasted and how much you used the old one before it failed.

[Rod Speed]

Bloody hell, why do you do that ?

[Tim+]

That might have been the case in the past but with current energy prices, we only light the room that we’re in. Not having any kids at home makes this a lot easier of course.

Tim

[Rod Speed]

I used to when I used PAR38s inside for my main lighting, in our very hot summers. Don't anymore now that I use Philips Hue leds instead.

I always have a light at my shoulder at the PC which is where I spend the vast bulk of my time. I read kindles on my PC and watch recorded free to air TV and streamed stuff there too, mainly because I play Freecell Pro when watching any videos or streamed stuff.

[Colin Bignell]

Because it is easy. I take a bag od washing in first thing in the morning, give it to the woman operating the laundrette and collect a bag of clean, neatly folded, washing around lunchtime.

[ARW]

Thanks for conforming it's a women's job.

I thought I was the only sexist pig on the newsgroup:-)

[zall]

Yes.

Can't see many actually being that stupid.

[Colin Bignell]

She does own the place.

;-)

[Paul]

Some day, you'll be able to buy these. These were already discussed in the newsgroup some time ago (Big Clive video).

The only question about those, is how they would last if your electricity is out-of-spec. They're not as sensitive as capacitor dropper bulbs, but they're not as bulletproof as SMPS either. The problem with SMPS, is the capacitor is baked while it runs, and the magic smoke comes out too soon. The LEDs never have a chance to degrade.

Back when LED bulbs came with metallic heatsinks, you could augment the cooling externally with bits of metal. The newer/cheaper ones, there's no good way to get the internal heat coupled efficiently into the air stream.

You can look at some take-aparts, to judge quality, but from year to year, these designs change and become "cheaper", so don't be surprised if the good-looking TCP is just as cheap as a competitor today.

"The Race to the Bottom: LED Bulbs..."

The diffuser on one of the bulbs, may be there because the small LEDs are a different colour than the big LEDs, and the diffuser mixes the light. You might see that approach on a 2700K (warm) lamp, while a 4500K lamp could get by without the usage of the small LEDs and give a (cold) light.

And while there is the CRI rating, to give some idea of the colour-quality, there are some dreadful LEDs out there, that you would unscrew and put back in the bulb-drawer. There are also beautiful LEDs. I have a 15W flood (only 60W equivalent), and the light from that is a spitting image of an incandescent. The LEDs are Nichia (Japanese) on an alumina substrate, and someone did a good job on the phosphor mix on those. But the company assembling the bulb, has a poor rating on SMPS design, so the base of that lamp is likely to be the part that smokes.

The topic is esoteric, the quality... vanishing with time.

Paul

[Mark Carver]

The lighting in our house is now 100% LED. Total electricity consumption in June is only 10% lower than it is in Dec and January

Of course the CH boiler consumes electricity, but conversely the fridge/freezer is working harder in the summer ?

[Bob Martin]

?????????????

[Andy Burns]

That day is already here ... 210 lm/W

[The Natural Philosopher]

Well apart from leaving out the vital bit, i.e. 1000 hours is about 3 hours use a day *for a year*, that all seems straightforward enough.

Does show that I ought to start replacing my halogen downlighters tho...

[Tim+]

Fine if you like cool white…. Not a fan myself.

Tim

[Andy Burns]

There is that, generally I prefer warm, but I do like cool for my study, seems to feel more for concentrating, less for relaxing.

I should think it's only a case of them swapping the yellow phosphor coating for a warm version, then hopefully making a BC22 version, and 100W as well as

40W/60W, then make them dimmable ...

[rick]

Only issue is that life of some LEDs is turning out be be nowhere near what is projected .... had several LED downlighters fail totally, and other start flickering needing swapping out. I know it depends on the manufacturer .... but when I built house I put in 12V QH as it was considered better than incandescent bulbs, and better efficiency.

Had quite a few transformers fail, as each did I changed to mains LED.

If you figure cost of change, and several early life failures of LED, very hard to quantify any savings

[Dave Plowman (News]

Yearly costs, pet. Always leave a little bit for the reader to do himself.

Had the figures to hand after talking to my brother. Who taught maths all his working life. But still guessed the purchase price was more important than running costs.