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# Energy saving lights watch

1. Does it waste more energy turning it on and off than turning it off?
2. Though I can't make sense of what you said, on a similar subject, it's more efficient to turn a light bulb off if you are going out of a room for more than 5 minutes, but if you are gonna be back in less than 5 mins then you use less energy leaving it on.

i think.
3. Surely it would depend on the energy expended heating up the bulb and bringing it into operation? Could always do some measurements of power against time and try to find out if you were inclined. Or you could laugh evilly at the environment
4. (Original post by darkenergy)
Does it waste more energy turning it on and off than turning it off?
I'm not completely certain what you are asking. However, as far as I know the current drawn by a lighttube (most energy-saving bulbs are just curled up light tubes ) is only moderately affected by its temperature. Thus it consumes a small initial spark of energy when you turn it on, then it consumes more or less the same amount of energy as you leave it on ( I think ). Thus the amount of energy it consumes is just proportional to the time you leave it on ( if you ignore the initial spark ).
5. (Original post by Jonatan)
I'm not completely certain what you are asking. However, as far as I know the current drawn by a lighttube (most energy-saving bulbs are just curled up light tubes ) is only moderately affected by its temperature. Thus it consumes a small initial spark of energy when you turn it on, then it consumes more or less the same amount of energy as you leave it on ( I think ). Thus the amount of energy it consumes is just proportional to the time you leave it on ( if you ignore the initial spark ).
This is incorrect for an Energy Saving Lightbulb. In a flurescent tube the mode of radiation is different from an incadecent bulb. An inert gas is used in to generate light. But how does an inert gas even conduct, let alone convert electrical energy to light? The inert gas must be ionized and turned into plasma.
So thus the 'small spark of energy' is a lot of electricity being used to ionize the entire content of the tube. In fact every fluorescent tube must have a large capacitor attached to them to start them, as they charge up the cap then ionize the gas with the energy. As to how much energy is used in this process I do not have the foggiest.

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