# Re: light bulb and tannins

```At 03:48 AM 01/19/2001 -0500, zxcvbob (Bob) wrote:
> > I have 2 questions.  One is about those twisty fluorescent bulbs that
> > are said to have the brightness of a 75 watt buld but only use 20
> > watts.  My question is when you are calculation the watts per gallon,
> > which number do you use?  Are those bad bulbs to use?
>
>You use the "20 watts" number, but you should discount it considerably
>(25 percent?) because the manufacturers' numbers are overly
>optimistic, and to account for the energy wasted by the intregrated
>ballasts.

At 03:48 PM 01/19/2001 -0500, Richard R also writes:
>Scott, they mean brightness 75watt of Incandescent light bulb while it uses
>only 20watts. It's only to compare. So you use the 20watt number.
>Bob, you don't have to discount anything. Number of Watts has nothing to do
>with output of the light bulb.
>It is like this : P = U x I ( P= V x I in Canada ), Power = Voltage x Current

I don't understand this reasoning. When people suggest a certain # of
watts/gallon they're making the recommendation based on brightness, not
power consumption. So if these bulbs really do put out the same brightness
as a 75-Watt bulb, why would you only consider them a 20-Watt bulb for
overall lighting calculations?

Daniel Segel

--
"Being humble is why I'm a great person."
Daniel A. Segel
dsegel at pacbell_net

```