Fluorescent Lighting

[TiTTieS_[CNTDN]]

Does anyone know anything much about the amount of energy these save compared with the amount that they require to start up?

I've heard that you are better off leaving them on while out of the room for a short while rather than turning them off. So the big question is: how long would you have to be out of the room in order for there to be no difference between switching off and leaving on? I hope this makes sense.

 

[Twizzle]

the question makes sense but the answer can be very technical and the savings can be very minor

depends whether you have a metal ballast, or electronic soft start ballast

also depends whether you are talking about plc (compact fluorescent generally round tubes) or the conventional 1 metres long tubes

they generally draw 3 to 4 times they rated amps on start up so there is not that much as we are talking about

at 13 cents per kilowatt hour and a conventional 36 watt tube, its costs .6 of a cent to start up

compact fluorescents would take a lot less to start up

 

[TiTTieS_[CNTDN]]

Cheers Twizzle. So it sounds like a possible saving of no more than a few dollars at most for the average household over the course of a year???

 

[Twizzle]

thats about right, depending on usage

 

[*Paul*]

My guess would be that a bigger factor would be that turning the light on and off shortens its life span, and hence require its replacement more often. So there'd be a balance between wasting energy by leaving them on, and having to replace them more frequently by turning them off (and then on again)

Can't see making too much of a difference either way.