Do light dimmers save much on the Electricity bill?

ronan45

Hiyas, Just wondering do dimmers save much on the bill? I LOVE dimmers as i am a big fan of warmly lit rooms IE my chandalier is on a dimmer and i normally set it to maximum dim. Max blows me eyes out.
Does this on a purely financial level save much money?
If you dim to 1/4 light on two 5 bulb 60 watt chandaliers do you save 3/4 on the ESB bill?
not a scab just wondering !

Bruthal

ronan45 wrote: »

Hiyas, Just wondering do dimmers save much on the bill? I LOVE dimmers as i am a big fan of warmly lit rooms IE my chandalier is on a dimmer and i normally set it to maximum dim. Max blows me eyes out.
Does this on a purely financial level save much money?
If you dim to 1/4 light on two 5 bulb 60 watt chandaliers do you save 3/4 on the ESB bill?
not a scab just wondering !

Your sure to reduce the loading somewhat. Probably would save the 3/4 of the lighting wattage alright. Or close to it anyway. But you wont of course reduce your overall esb bill by 3/4, just 3/4 of what that light fitting itself is using while dimmed to 1/4 brightness.

ronan45

robbie7730 wrote: »

Your sure to reduce the loading somewhat. Probably would save the 3/4 of the lighting wattage alright. Or close to it anyway. But you wont of course reduce your overall esb bill by 3/4, just 3/4 of what that light fitting itself is using while dimmed to 1/4 brightness.

HI robbie yes of course not the whole bill but the lights that are in use at that moment in time. Hmmm SO I wonder.. would a fully dimmed bulb be the equivalent of an energy saving bulb ! Possibly not far off !
Cheers rob

Sofiztikated

You're still losing a lot of energy to heat.

Why not try dimmable CFL's?

Bruthal

ronan45 wrote: »

HI robbie yes of course not the whole bill but the lights that are in use at that moment in time. Hmmm SO I wonder.. would a fully dimmed bulb be the equivalent of an energy saving bulb ! Possibly not far off !
Cheers rob

Yes it would be close enough, although dimmable low wattage ones are available also, which would be even lower wattage. Probably not suitable for your chandalier though looks wise.

One experiment you could do is turn off everything in the house and view your esb meter to see its stopped. Then turn on the light up to full brightness and see notice the meter rotatation speed. Now dim it fully down and see the meter slowing, it will be easier to see it happen if you watch the meter and someone else dims the light. Its easier to see the speed slowing if nothing else is on.

beanie10

I was told years ago that dimmers use up power, the more you dim it the more power it uses hencr the buzzing noise. I could be wrong.

eoghan.geraghty

Dimming incandescent bulbs will save you very little, nowhere near as efficient as a cfl bulb.

Bruthal

beanie10 wrote: »

I was told years ago that dimmers use up power, the more you dim it the more power it uses hencr the buzzing noise. I could be wrong.

I was thinking of that exact same thing myself when writing my first reply, but what actually happens is the on time to off time in the dimmer is varied, this is how the light is dimmed, its the increased switching of and on that causes the buzzing. I think its worse with cheaper dimmers. Some can even cause buzzing in the bulb filament

Bruthal

eoghan.geraghty wrote: »

Dimming incandescent bulbs will save you very little, nowhere near as efficient as a cfl bulb.

I dont think some chandaliers look great with cfl`s though.

paddy147

beanie10 wrote: »

I was told years ago that dimmers use up power, the more you dim it the more power it uses hencr the buzzing noise. I could be wrong.

I thought the buzzing noise increases and comes from the bulbs/light fitting and not the dimmer???


or am I wrong???

Bruthal

paddy147 wrote: »

I thought the buzzing noise increases and comes from the bulbs/light fitting and not the dimmer???


or am I wrong???

That does happen alright, i mentioned it in post #8 i think

2011

Dimming incandescent bulbs will save you very little, nowhere near as efficient as a cfl bulb.

This is very true.

However in my opinion CFLs do not produce a very nice light. I agree that they are very effective and suitable in many circumstances, but not in a kitchen, dining room, TV room etc.

The type of light that people want to dim is generally a light that would look appalling with a CFL! I use them in the utility room, garden shed, side light on a house, driveway lights etc.

I think many people get too hung up on the energy consumption from lighting of domestic premises. In general lighting only represents a very small portion of the electricity bill for the average home.

paddy147

eoghan.geraghty wrote: »

Dimming incandescent bulbs will save you very little, nowhere near as efficient as a cfl bulb.

Dimmable 15W CFL bulbs,1 on the right is dimmed by around 50%.;)

paddy147

2011 wrote: »

The type of light that people want to dim is generally a light that would look appalling with a CFL!




I think many people get too hung up on the energy consumption from lighting of domestic premises. In general lighting only represents a very small portion of the electricity bill for the average home.

I have to object to both comments.


CFL bulbs are now being made in propper warm white and are fully dimmable too (see my pic above).





My leccy bils have plummeted down since changing every bulb in my house over to LED and CFL.

And as a well known supermarket store says ......."Every littlle helps".


Or to quote Weeman from Jackass...."Its not much,but its somethin".

Bruthal

2011 wrote: »

This is very true.

However in my opinion CFLs do not produce a very nice light. I agree that they are very effective and suitable in many circumstances, but not in a kitchen, dining room, TV room etc.

The type of light that people want to dim is generally a light that would look appalling with a CFL! I use them in the utility room, garden shed, side light on a house, driveway lights etc.

I think many people get too hung up on the energy consumption from lighting of domestic premises. In general lighting only represents a very small portion of the electricity bill for the average home.

The CFL being more efficient part is true.
Im not sure its true to say dimming a 100w bulb does not reduce its running cost though. It is true to say a CFL is more efficient, but they are 2 different things being confused. How efficient a CFL is has no bearing on whether dimming an incandescent bulb will reduce its watts usage. If a 100w bulb is dimmed to 20 percent its full brightness, it must have a fair drop in watts used.

Bruthal

paddy147 wrote: »

My leccy bils have plummeted down since changing every bulb in my house over to LED and CFL.

With the amount of lights you have in your house im not surprised:pac:

paddy147

robbie7730 wrote: »

With the amount of lights you have in your house im not surprised:pac:

Indeed.:pac::D

Im even in the process of changing over from the Bayonet fitment 11w CFL bulbs to 3w Led bulbs now,nice lamp shade or fitting over them and the light is still nice.

ronan45

paddy147 wrote: »

Indeed.:pac::D

Im even in the process of changing over from the Bayonet fitment 11w CFL bulbs to 3w Led bulbs now,nice lamp shade or fitting over them and the light is still nice.

So these bayonet bulbs LED are they as nice as the standard ones? LED bulbs never heard of them!

paddy147

ronan45 wrote: »

So these bayonet bulbs LED are they as nice as the standard ones? LED bulbs never heard of them!

Depends on a persons personal taste,but doesnt bother me.

When lit,it looks like a bit of a mini UFO hanging below the ceiling.:D


So far,anyone who has been in my house and seen them,has commented on them and that they look like a UFO and kinda funky.

All Im interested in,is that they are 3w and give off good light,thats all that matters to me.

Stoner

http://www.ehow.com/about_6458578_incandescent-dimmer-work_.html

ronan45

Stoner wrote: »

http://www.ehow.com/about_6458578_incandescent-dimmer-work_.html

Cheers Stoner!:D

SO IT DOES SAVE A HELL OF A LOT !

Dimmer Advantages

Dimmers also save money. A 50 percent reduction in the light level can result in a 40 percent cost savings on electricity. Dimmed light bulbs also last longer than those operated at full power.

2011

robbie7730 wrote: »

Im not sure its true to say dimming a 100w bulb does not reduce its running cost though.

I never suggested that it would not reduce running costs.

How efficient a CFL is has no bearing on whether dimming an incandescent bulb will reduce its watts usage. If a 100w bulb is dimmed to 20 percent its full brightness, it must have a fair drop in watts used.

I agree and did not suggest otherwise.

DoesNotCompute

paddy147 wrote: »

Indeed.:pac::D

Im even in the process of changing over from the Bayonet fitment 11w CFL bulbs to 3w Led bulbs now,nice lamp shade or fitting over them and the light is still nice.

+1000

LED bulbs are da bomb :cool:

I'm using 6W Pharox LED bulbs myself in the upstairs landing & toilet, downstairs entrance and toilet. Nice light off them, very efficient, cheap to run, and they're very bright considering they're only using 6W.

DoesNotCompute

ronan45 wrote: »

Dimmers also save money. A 50 percent reduction in the light level can result in a 40 percent cost savings on electricity.

How true is this though? Surely the dimmer is using energy, as it is essentially a big resistor, and when the dimmer is at, say, 20% any current that would have been passing through the bulb at full power, is instead being converted into heat (current meets resistance and heat is produced) and sound energy (buzzing noise), thereby not actually saving any money?

don't think i've explained that very well, but you get the idea?

paddy147

DoesNotCompute wrote: »

+1000

LED bulbs are da bomb :cool:

I'm using 6W Pharox LED bulbs myself in the upstairs landing & toilet, downstairs entrance and toilet. Nice light off them, very efficient, cheap to run, and they're very bright considering they're only using 6W.

I like the looks of them.

Whats the light quality like on the bulbs you are using?

Are they a propper warm white,and would they be as bright as a normal 60W bulb?

Thanks.:)

DoesNotCompute

Light quality is good, they come in warm white, not sure if they come in daylight white or cool white. They are just as bright as a 60W bulb.

The light off of them can be a bit "unnatural", and tends to be directional, pointing in a conical manner, rather than in all directions. You don't really notice this though, if you put a light shade around them.

Here's a video though: http://www.youtube.com/watch?v=3-OJOkbHBGw

They cost a bomb though, €25 a pop :eek:

And I'm not sure if they're protected against voltage spikes/surges

.G.

DoesNotCompute wrote: »

How true is this though? Surely the dimmer is using energy, as it is essentially a big resistor, and when the dimmer is at, say, 20% any current that would have been passing through the bulb at full power, is instead being converted into heat (current meets resistance and heat is produced) and sound energy (buzzing noise), thereby not actually saving any money?

don't think i've explained that very well, but you get the idea?

Modern dimmers use triacs or thyristors as well as resistors and they limit the amount of current flowing in the circuit.

Less current=less power=less money

Bruthal

2011 wrote: »

I never suggested that it would not reduce running costs.




I agree and did not suggest otherwise.

I was just going by your post number 12. If you say something which had 2 parts is true i`d assume you agree with both parts. No big deal really. Probably just my useless reading as usual:)

GarRoIT

I don't know if it would save electricity or anything, but electricity is charged at 1 unit per 1000 watts per hour or 1 unit = 1KW/h A unit of electricity costs between about 12c and 15c and a 100watt buld uses 100watts per hour, so a 100 watt bulb at full power costs you about 14 cent every 10 hours or 1.4cent per hour so its not much of a saving really, it looks nice though.

Bruthal

DoesNotCompute wrote: »

How true is this though? Surely the dimmer is using energy, as it is essentially a big resistor, and when the dimmer is at, say, 20% any current that would have been passing through the bulb at full power, is instead being converted into heat (current meets resistance and heat is produced) and sound energy (buzzing noise), thereby not actually saving any money?

For the first part about dimmer if it was a resistor.
Well if you have a 100 watt bulb, this has a resistance of about 530 ohms when its on(resistance far lower when its cold). Now put in a resistor of 1000 ohms in series with the bulb. Now you have roughly 0.15 amps flowing, in the circuit. The bulb now outputs (I^2xR) 530 x 0.15 x 0.15=11 watts. The resistor now outputs 1000 x 0.15 x 0.15=22 watts. This would be a lot of watts for a resistor, and it would give off 22 watts of heat like you suggest, but still the overall watts of the circuit is 33 watts instead of 100 watts.

But as i said in post #8 i think, and i think stoner put a link to something similar, dimmers dont use resistors to dim the bulb, they use on off switching of the supply to the bulb. So the more the ratio of off to on, the dimmer the bulb, and watts are only being used during the on time.

2011

paddy147 wrote: »

CFL bulbs are now being made in propper warm white and are fully dimmable too (see my pic above).

I agree that CFL lamps have a higher efficacy (better lumens to watt ratio), can be dimmed and are available in "warm white".

In terms of light quality I feel that they are not as good as say a 12V dichroic lamp.

My leccy bils have plummeted down since changing every bulb in my house over to LED and CFL.

Well you must have a lot of lights on a lot of the time them!

I live on my own and I generally have lights only on in 1 room at a time. At most I would guess that I use far less than 100 watts of lighting for far less than 6 hours a day. In other words 0.6 of a unit per day at a cost of €0.12 per day which is well under €50 per year in lighting costs. In the rooms that I spend most of my time in I have dimmers which provide further savings.

Now I could go and change all of the lamps in my home for CFLs or LEDs and after a few years I would break even. I have some very nice lighting in my house (thanks Bob Bushell) and I feel that it is worth an extra 10 or €20 per year to get the quality of light that I want. Each to their own I guess.

I have some CFLs in my home in rooms like the utility etc.

I have small energy bills relitive to others because I focus on saving energy on appliances that use much more energy than I use on lighting.

Stoners link above clearly shows that a dramatic savings can be made on lighting but only if you have large lighting bills (as some people do).