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JB

Low energy light bulbs

Do these save enough energy to warrant replacing incandescent light bulbs immediately or is it better to use the incandescent bulbs until they burn out and then replace them?
tahir

In our house I changed all the ones that got pretty constant usage immediately and then waited for the rest to die before replacing
tigger

http://www.yourwelcome.co.uk/html/savings.html

Is this any help?
Jonnyboy

We changed all ours in one go, on the grounds that 'normal' bulbs are so cheap it's hardly worth doing the math.

We've had two low voltage lamps fail in a year. One just died and another I walloped by mistake,
JB

tigger wrote:
http://www.yourwelcome.co.uk/html/savings.html

Is this any help?


Yes, but I was also interested in how much energy does it cost to make the low energy bulbs. Based on that a low energy 11w bulb would save 34.30 over its life or 3.43 over the life of a sinlge incandescent bulb. Assuming the incandescent is half way though its life then replacing the bulb immediately rather than waiting would save about 1.70 which makes it a borderline choice as to whether it's worth doing so.

OTOH if the same bulb saves 49W then replacing it now would save on average 24 KWh. But how much energy (or material cost for that matter) is used in manufacturing, packaging, shipping etc. such a bulb?
alisjs

Tesco are selling a wide range of low energy light bulbs at half price ......useful if you need awkward fittings
Tinks

Got six at homebase today. BOGOF and it's 1.99, so a quid each on their low energy bulbs. Not bad,eh?
cab

For those lights that keep getting turned on and off (like the loo) we've kept our old normal bulbs. I figure that for that kidn of use its maybe as good if not better to use an ordinary bulb, and it saves us throwing the old ones out.
countryman

This is a good point cab, i hadnt thought of that, DOES ANYONE KNOW WHY LOW ENERGY DONT GET HOT-ITS A MYSTERY TO ME.
Green Man

I still don't like the quality of light from them in my living room or dinning room. A warmer glow from traditional bulbs allows me to keep the public rooms a couple of degrees cooler while it looks cosier. If that makes sense?
I most certainly have them in kitchen lamps, high hallways and door lights, and would quite happily use them in living room if they were warmer toned and could be dimmed, via the ring circuit I have there.
Jonnyboy

countryman wrote:
This is a good point cab, i hadnt thought of that, DOES ANYONE KNOW WHY LOW ENERGY DONT GET HOT-ITS A MYSTERY TO ME.


It's because they convert electricity to light with far more efficiency. The heat from a incandescent bulb is a wasted 'loss' from the conversion process.
So, as a very rough calculation, 11w low voltage gives the same light as a 60w bulb. So with a normal bulb you have 49w being used solely to keep the moths warm.
Green Man

Not only moths but your house too. It might not be a efficient heat source? But it certainly is not wasted heat in the winter in my house. Every little helps Wink
Tinks

Strike a match and invite the neighbours round Laughing
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