The amount of lumens that are emitted from a fluorescent lamp is given approximately by the luminance (cd/m^2) times the length (m) times the diameter (m) times pi squared. Unfortunately, we don't usually know the luminance.
The number of lumens varies greatly from bulb to bulb, across the various types of fluorescent technologies. One rule of thumb, that won't apply to every type of fluorescent lamp, is to multiply the rated wattage by 80 (lm/W) to get the number of lumens.
If so, a 40 watt fluorescent lamp will output about 3200 lumens, but, as you will find elsewhere, on Wikipedia:-
100 W tungsten incandescent (220 V): 1380 lm
100 W tungsten incandescent (120 V): 1750 lm.
So the above information does not seem quite right for a 40 watt fluorescent bulb.
Furthermore, for the analysis to be accurate, one has to realize that light can be either focused as in a laser or dispersive as in an incandescent bulb or fluorescent tube. Lumen ratings given with a square meter to distance ratio would help a lot but are not often given.
Technical information is sometimes printed on the boxes which fluorescent tubes come in from the factory. For instance, on one box of compacts fluorescents it states that a 100 watt compact fluorescent will put out 1700 lumens. Dispersive of course. For further information see the Related links shown below.
This will open a can of worms, since you can't really convert Watts to Lumins. Watts is heat and Lumins is percieved light.
Just one bone of contention is that Watts takes no account of light generated out of the visible spectrum and Lumins is all about Visible spectrum anything outside the visible human spectrum is 0 Lumins.
But according to one online converter (How?) the answer is;
58 Watts per centemetre squared = 39614 Lumins per centemetre squared @ 555 nM.
About 80%. An incandescent bulb produces 12 lumens per watt, (15 for halogen) while a CFL produces about 60 lumens per watt.
The number of lumens produced by a 34 watt bulb depends on the type of bulb. As a general estimation, a standard incandescent bulb produces around 400-500 lumens per 40 watts, so a 34 watt bulb would likely produce slightly fewer lumens, around 350-450 lumens. However, different bulb technologies such as LED or CFL can produce a higher number of lumens with lower wattage.
Bulb brightness is measured in lumens which express the amount of light produced, while the electric power used is measured in watts. The typical efficiency of some different types of bulb is: Incandescent 12 lumens per watt Halogen 17 lumens per watt CFL (compact fluorescent) 50-60 lumens/watt LED (light-emitting diodes) 90-100 lumens/watt.
a 42 watt cfl give off 2800 lumens
Incandescent produces about 10 lumens of light per watt of electricity Halogen produces about 13 lumens per watt Fluorescent and CFL produce about 50 lumens per watt So Fluorescent is the most efficient.
Incandescent: 10-12 lumens per watt CFL: 50 lumens per watt.
This is a bit less light than a 40W incandescent bulb (much less than a 9-watt CFL bulb, but twice as much as a 5-watt CFL mini-bulb).
A 150-watt light bulb uses energy at the rate of 150 watts, when it's turned on.
About 80%. An incandescent bulb produces 12 lumens per watt, (15 for halogen) while a CFL produces about 60 lumens per watt.
The number of lumens produced by a 34 watt bulb depends on the type of bulb. As a general estimation, a standard incandescent bulb produces around 400-500 lumens per 40 watts, so a 34 watt bulb would likely produce slightly fewer lumens, around 350-450 lumens. However, different bulb technologies such as LED or CFL can produce a higher number of lumens with lower wattage.
It's about 600 lumens. The same brightness comes from a 12 Watt compact fluorescent light (CFL).
Bulb brightness is measured in lumens which express the amount of light produced, while the electric power used is measured in watts. The typical efficiency of some different types of bulb is: Incandescent 12 lumens per watt Halogen 17 lumens per watt CFL (compact fluorescent) 50-60 lumens/watt LED (light-emitting diodes) 90-100 lumens/watt.
a 42 watt cfl give off 2800 lumens
Incandescent produces about 10 lumens of light per watt of electricity Halogen produces about 13 lumens per watt Fluorescent and CFL produce about 50 lumens per watt So Fluorescent is the most efficient.
Compact fluorescent bulbs are widely used because they use one fifth of the electric power to provide the same amount of light as an incandescent bulb. Incandescent: 12 lumens per watt Halogen: 15 lumens per watt CFL: 50-60 lumens per watt LED: 100 lumens per watt High-pressure sodium: 200 lumens per watt
A 23 watt cfl will give off roughly 1600 lumens. However that is only within a few inches of the bulb.
In this context, Watts are a measure of electrical power and lumens a measure of light output. So, depending on the efficiency of your light source the equivalency will vary dramatically. For example, a 60 watt conventional light bulb typically gives off 800 lumens. A frosted 60 watt bulb may only give off 500 lumens. A 13 watt CFL will give off that same 800 lumens, which is why 13 watt CFLs are often (erroneously) called 60 watt bulbs.