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Rant: Energy-saving...
 

[Closed] Rant: Energy-saving lightbulbs

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Now, I like a pointless rant as much as the next man, but this "modern light bulbs are rubbish" thing confuses me. Why not simply buy a bulb that has the colour temperature and light output that you require?


 
Posted : 21/12/2009 6:02 pm
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Why not simply buy a bulb that has the colour temperature and light output that you require?

And how do you do that when the [url= http://news.bbc.co.uk/1/hi/magazine/8406923.stm ]European Commission[/url] and [url= http://www.telegraph.co.uk/earth/earthnews/6693174/Energy-saving-bulbs-are-not-labelled-correctly-according-to-Defra-study.html ]DEFRA[/url] admit that manufacturers lie on the specs and labelling of these bulbs?

Allegedly.


 
Posted : 21/12/2009 6:11 pm
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and when she turns on the 2000w heater I do wonder if using a few less 100w bulbs is really gonna make much difference....

On one hand, yes you are right the energy consumed in heating, cooling and domestic ho****er are much more significant than lighting for example, however every bit helps. Also factor in the public buidlings (schools, hospitals etc) that are least efficient of all, or offices and shops that 'drink' energy at scary rates due to poor design and understanding or blindnesses to the issue.

Bulbs are also 'low hanging fruit' - easy, cheap and effective. Try saying that about (for example) insulating and draft-proofing all the cute, solid walled terraces and cottages that litter the UK...

Good bulbs are worth it, and we are slowly buying LED ones (our new house has many spots ) and so far they are great.


 
Posted : 21/12/2009 6:11 pm
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Most of the new bulbs are the equivilent of walking about in a coal mine.

I would feel a bit better about being forced to use them if all office blocks were forced to turn lights out instead of running them all night.

If shops and offices had to be designed with enough windows and light wells to reduce thier need for artificial lighting - most shops have blanked out any windows, other than front displays, so have to use masses of artificial lights.

If a maximum temp level was set for shop heating (recent article in paper saying they are heated higher than summer temps abroad!)

If shops were banned from leaving all thier doors open in the winter, with heaters on full blast, trying to still keep the building warm.

In comparison, my 2 100 watt bulbs look pretty harmless. The rest in the house are low energy.


 
Posted : 22/12/2009 10:40 am
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From linky above...

So, to get the brightness of a traditional 60-watt bulb, choose a 15-watt CFL bulb.

Either I'm getting amazing bulbs or the world is going nuts. My 11W bulbs more than replace my 60Wers.

Who wants a clinical 100W floodlighting effect in the house?


 
Posted : 22/12/2009 10:49 am
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I suggest you're getting good bulbs (what brand are they by the way?).

As I said my 15W, supposedly 75W equivalent, is more like a 35W equivalent. I don't need clinical floodlighting, but I'd like to be able to read the paper.


 
Posted : 22/12/2009 11:46 am
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Hora moaning about lightbulbs [b]again[/b]??
Have you tried using bulbs with the correct output yet?


 
Posted : 22/12/2009 12:42 pm
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If shops and offices had to be designed with enough windows and light wells to reduce thier need for artificial lighting - most shops have blanked out any windows, other than front displays, so have to use masses of artificial lights.

Ah, but then the passive solar gain would be so high that they turn on the a/c....


 
Posted : 22/12/2009 12:43 pm
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[i]So a saving of 4x 65W (say) per household. Assuming around 20 million households and all the lights on at the same time that's 5.2GW! I believe Drax is around 2.5GW at peak load so that's not really squat.[/i]

I think the saving will be a bit less (though still substantial)
A 100W bulb is a purely resistive load and the volts and amps are in phase. So the leccy supplier have 100VA of generating power (ignoring transmission losses) to drive it.
CFLs at the moment typically have a power factor of 0.5 This means that although a 25W CFL will register a consumption of 25W watts on your meter, because of the intermitent current they draw, the supplier has to provide 50VA of generating power, rather than the intuitive 25VA. Also if the resitive heating from the light bulbs will have to be transfered to your heating system instead.

Of course that's not to say that CFLs don't save energy and aren't worthwhile, just that the headline savings are not as much as people first imagine.


 
Posted : 22/12/2009 12:57 pm
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Smart @arse!


 
Posted : 22/12/2009 12:59 pm
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Also if the resitive heating from the light bulbs will have to be transfered to your heating system instead.

I looked into this, and it makes b*gg*r all difference in the average 'heat leaking' UK house, it would if you live in a Passive Haus++/AECB Gold+ house


 
Posted : 22/12/2009 1:17 pm
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Out of interest why does it not make any difference? Is not 400W of heat 400W heat? I mean you could quite reasonably argue that you won't notice the heat difference, but that's the same argument as you won't notice if you turn the thermostat down 0.1 degree. In both cases i'm sure it will feel exactly the same, and use less energy. But in both cases you'll just using less energy becuase you're keeping the place slightly cooler rather than any efficiency gain.
Though I'm quite prepared to believe that I've missed something, as it's your area of expertise.


 
Posted : 22/12/2009 1:46 pm
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because the heating needed for the average (UK insulated and drafty) room is so high, and its not 400w of heat (some is light), plus its high up (usually) and not where occupants benefit.

Don't get me wrontg, it does something. PassiveHaus calculations take account of it, and how much water is in your toilet cistern and at what incoming temp (for example), its just in most houses it is naff all.


 
Posted : 22/12/2009 3:22 pm
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