Energy saving bulbs

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Energy saving bulbs
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Jonnyboy

Joined: 29 Oct 2004
Posts: 23956
Location: under some rain.

Posted: Wed Aug 17, 05 11:02 pm Post subject: Energy saving bulbs

If you havenï¿½t already switched to low energy light bulbs, then hopefully this will encourage you to make the change.

The traditional incandescent light bulb, seen in most houses, works by passing electricity through a resistive wire, this wire becomes hot, radiates heat and emits light as a by-product, the wire (filament) is prevented from burning by an inert gas within the bulb. This process uses approximately 10% of the input energy to produce light, whilst 90% of the energy is wasted through heat. Basically itï¿½s the same principle as the 2 bar electric fire that used to heat your living room in the seventies.

Energy saving light bulbs are a form of fluorescent lighting. Argon gas is encased within the bulb (which is coated with a layer of phosphor). When electricity passes through the gas, it emits ultraviolet rays which cause the phosphor coating to glow. This process is approximately 80% more efficient, therefore a 12w energy saving bulb is equivalent to a 60w standard bulb.

Energy efficient lamps also last far longer, a traditional bulb lasts for approximately 1000 hours, whilst a low energy version will typically last between 8000 ï¿½ 15000 hours.

If you change one bulb in your house to a low voltage version, it will pay for itself within a year, dependant upon how it is used and itï¿½s lifespan it can save you up to ï¿½75 over over its lifespan. Plus you have helped reduce harmful greenhouse gas emissions.

The best places to start to replace your bulbs are in areas where the light is usually left on for longer periods, low voltage bulbs operate poorly in areas of low temperature, so they are not particularly bright when used in your garage or outside.

Some local councils will even give grants or financial assistance when replacing bulbs, check with your local authority or electricity supplier.

jema
Downsizer Moderator

Joined: 28 Oct 2004
Posts: 28239
Location: escaped from Swindon

Posted: Thu Aug 18, 05 5:06 am Post subject:
Two more tips on alternatives. If using mains voltage Halogens which are a bit more efficient than normal bulbs, then use a dimmer switch. As mains voltage halogens cannot handle being switched on instantly. They will blow very quickly. LED bulbs are very efficient, but as of now only suitable for very low light needs.

wellington womble

Joined: 08 Nov 2004
Posts: 15051
Location: East Midlands

Posted: Thu Aug 18, 05 9:26 am Post subject:

Are mains voltage halogens those stupid GU10's that cost a fiver each and blow all the time? we've got two lots of them, and they drive me nutty. We tried a dimmer with them, but it made dangerous buzzing sounds and never worked.

Oddly, the low voltage halogens seem to give just as much light, and never blow!

Jonnyboy, can you give me a source for that? Then I can get himself to pass it on to his customers, and they might see sense and stop getting us to to remove the energy saving light fittings!

wellington womble

Joined: 08 Nov 2004
Posts: 15051
Location: East Midlands

Posted: Thu Aug 18, 05 9:27 am Post subject:
And they really hot, too - I bet they waste loads of energy as heat! rant over!

Behemoth

Joined: 01 Dec 2004
Posts: 19023
Location: Leeds

Posted: Thu Aug 18, 05 9:36 am Post subject:
We have them in the kjitchen and they provide underfloor heating for the bathroom.

dougal

Joined: 15 Jan 2005
Posts: 7184
Location: South Kent

Posted: Thu Aug 18, 05 9:37 am Post subject:

wellington womble wrote:

...I bet they waste loads of energy as heat!

The wattage of a bulb tells you exactly how much *heat* it produces.

Different technologies produce different amounts of *light* per watt of *energy* consumption...

Personally, I think that "energy saving" bulbs are an abomination for living quarters.
They do save energy, and are splendid for lights that must be left on for long periods, where appearance hardly matters - eg security lighting.
But the *colour* of the light they produce is *incomplete*.

Get a paint colour chart.
Sit at a table with two table lamps.
View the chart under an energy saving bulb only, then a halogen only, then again under the energy saving one.
The colour from the energy saving bulds is simply horrible.

IMHO there are more pleasant ways to save more energy...

dougal

Joined: 15 Jan 2005
Posts: 7184
Location: South Kent

Posted: Thu Aug 18, 05 9:46 am Post subject:
A couple of extra points I explained about colour perception in a previous thread on energy saving bulbs https://forum.downsizer.net/about1072.html Halogen bulbs' reflectors tend to focus the heat (infra red) as well as the visible light into a 'beam' - so the lighted areas also feel 'warmer'. And being smaller, people mount them much closer to things, which may then be scorched!

Jonnyboy

Joined: 29 Oct 2004
Posts: 23956
Location: under some rain.

Posted: Thu Aug 18, 05 9:46 am Post subject:
Energy saving bulbs don't work too well with dimmers, that is one of the small drawbacks. But as an energy saving device they work fantastically well, if more poeple switched to them then the cumulative energy saved would be huge. Plus they make financial sense. I haven't conducted my own test, but the manufacturers claim that the light output has been improved to produce a more natural light.

judith

Joined: 16 Dec 2004
Posts: 22789
Location: Montgomeryshire

Posted: Thu Aug 18, 05 9:49 am Post subject:

We have an eclectic mix of bulbs around the house. Where "instant light" is needed, only an incandescent bulb will do. For general background and long-term lighting we use LV fluorescents and a couple of old-fashioned striplights, and we have a few halogens, particularly in the kitchen, as task lighting. (Although for close-up task lighting I have to use incandescents as the halogens give me a headache). Very much horses for courses.

And, of course, if you switch a light off when you aren't in the room, it isn't using any energy at all!

Treacodactyl
Downsizer Moderator

Joined: 28 Oct 2004
Posts: 25795
Location: Jumping on the bandwagon of opportunism

Posted: Thu Aug 18, 05 11:27 am Post subject:

I went through a phase of using energy saving bulbs but I found the often blew just as often as a normal bulb. Not sure if our power supply was any more dodgy than anyone else. I now only use them in the one or two rooms where the light is often on. I still think far more should be done to get people to turn lights off, most of the houses round here have most of the rooms lit up at night and a few 500W outside lights on for good measure.

Andy B

Joined: 12 Jan 2005
Posts: 3920
Location: Brum

Posted: Thu Aug 18, 05 11:33 am Post subject:
They may be cost effective at the user end! but they look more complex to make than an ordinary bulb, so are they less cost effective at the manufacture end.

Jonnyboy

Joined: 29 Oct 2004
Posts: 23956
Location: under some rain.

Posted: Thu Aug 18, 05 11:41 am Post subject:

Andy B wrote:

They may be cost effective at the user end! but they look more complex to make than an ordinary bulb, so are they less cost effective at the manufacture end.

Probably, but you also have economies of scale in volume manufacturing, as more people adopt them then they come down in price. But you need to compare it to their average lifespan, and compare the process to make one low voltage bulb to between 8 and 15 ordinary bulbs.

Andy B

Joined: 12 Jan 2005
Posts: 3920
Location: Brum

Posted: Thu Aug 18, 05 11:54 am Post subject:
I do use them. But in Brum it never gets truly dark. I can walk around the house at 2 in the morning and see perfectly well.

jema
Downsizer Moderator

Joined: 28 Oct 2004
Posts: 28239
Location: escaped from Swindon

Posted: Thu Sep 08, 05 9:09 am Post subject:

Well in the Kitchen I am now set up with an over cooker light, an over worktop florescent, and two dimmer switches powering on group of all LED bulbs, and one with two halogens and two LEDs.

The LEDs are simply too pathetic by themselve, and the newly installed dimmer switches should prevent the Halogens from blowing continually.

Hopefully all together this should be energy saving, whilst still giving enough light. I do have to work in a dark kitchen, and as ours is lit mainly bu a north facing window, the lights do tend to be on more often than not

tawny owl

Joined: 29 Apr 2005
Posts: 563
Location: Hampshire

Posted: Thu Sep 08, 05 12:48 pm Post subject:

Treacodactyl wrote:

I found they blew even more often, and that's not cheap! I turn off the lights now too. I've got an ESB in the garage and in the spare bedrooms, but anywhere I'm going to be for any period of time has halogens, as I find the light from the ESBs gives me very bad headaches.

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