My son told me that turning on a flourescent light takes as much energy as running it for an hour. True?

Answer 1

Absolutely Untrue Rubbish.......

To start a fluorescent lamp requires a high voltage kick to allow the electrons to commence flowing from end to end. The high voltage kick could be several thousand volts but is an intantaneous surge for several milli seconds. The inertia of the disc in the kWHr meter will restrict the speed of the discs rotation. This together with the small amount of time, will not cause the kWHr meter to register the start.

You can check this out for yourself by turning off every thing in the house so that the kWHr meter is not registering, then have someone turn on the fluorescent light. You will see the disc start to turn when the light is turned on.

Source: Electrical engineer with over 50yrs experience.

Answer 2

No, that is not true. To understand why you need to understand that power is the rate of using energy, and watts is a unit of power, not a unit of energy. One 40 watt bulb running for an hour uses the same amount of energy as 60 bulbs of 40 watts each running for a minute, or the same as 3,600 bulbs of 40 watts each running for a second. So if your single 40 watt light used an hour of energy in the first second after you turned it on, it would be like you had 3,600 lights all running at the same time for that one second, which would be 144,000 watts for that first second. At 110 volts you need about 1,309 amps to get 144,000 watts, because volts X amps = watts. 1,309 amps would definitely trip your typical 30 amp circuit breaker.

However I have heard that turning on a fluorescent light reduces it's lifetime. For example, turning it on and then immediately off again uses up 1 hour of the light's lifetime, while turning it on and 10 hours later turning it off uses up 11 hours of its lifetime. So the problem with turning them on and off a lot is not increased electricity usage, it is decreased service life; it will burn out sooner.

Answer 3

Its tosh.

It requires very little energy to start a fluorescent tube.

However, continually starting a tube shortens its life. As well as consting you money, there is also an energy cost in manufacturing tube.

As a results greenhouse.gov.au estimates that you should turn off a fluorescent tube if you will not need it again for 10 minutes or more, leave it on otherwise.

Answer 4

It's said to be that but I have no way of testing it to prove it.
Fluorescent lights use a starter and a ballast to operate and the gas that is inside the tube gets "excited" becomes hot and produces light, once that starts it requires less electric to maintain the heat for the lighted gases.

Answer 5

Fluorescent lighting is more efficient than incandescent lighting. a 7 watt fluorescent light will emit as much light as a 30 watt or 40 watt incandescent light ( not sure about the math here). Most fluorescent lights now have this equivalence table on their packaging.

Answer 6

true for fluorescent tubes -tubes that have starters - the starter must heat up. also switching these on/off will make them last considerably shorter - u have to replace the starter or the tube or both

not true for fluorescent bulbs (i mean those that use much less energy and last much more than normal bulbs and can be screwed into the same lamp as normal bulbs) these have no starter - is that clear?

Answer 7

that is close,,,the inital trip of the ballast requires as much energy as it does to run the light for a long period,,,

Answer 8

May be.