Incandescent vs
Fluorescent bulbs and globes
Pros and
Cons
Had this dilemma - whether to choose one over
the other (pros and cons to go incandescent vs fluorescent.)
Could
the best way to decide be based on
someone else's
experience?
One
day ...
how the shift started
We
just realised that
one too many bulb had become short lived.
It was as if manufacturers were cutting too many corners.
Kind of
saying - we invested enough R&D into
other
light technologies
it was time to put our money where our
mouth was. In other words,
manufacturers have already decided where to tilt the incandescent vs
fluorescent debate.
Jump
to Incandescent
vs Fluorescent
wattage
comparison >>
We started
using fluorescent bulbs
there and then. (We
are quite cautious with LED lights.) But trial and error is
always the way
as there are already a lot of places
and uses where even fluorescent bulbs will not suffice. Still,
wherever we can
we replace our incandescent bulbs with fluorescent ones.
Not to mention that I like the
silly
look
you can
have with fluorescent light bulbs. In a lamp designed for an
incandescent, similar wattage fluorescent bulbs will be too big for
their own good. They will stick out - a bit like curious little light
creatures.
Increase this effect by deliberately
using spiral bulbs instead of pear shaped ones. Not for the
pedantic!
Over the period of several years
now, we had only one bad experience. See, incandescent bulbs burn out
very unpredictably. (Quite often at the worst possible time.) I don't
know how it will be with fluorescents on the long run though. For
many-many months now
we didn't have to replace any of them. But one we did. Read on to find
out why
...
Coloration
of incandescent vs fluorescent bulbs
Incandescent
is generally warm white due to the red and infra red
component.
Fluorescents
can
have various light effects due to
different color temperatures.
Usage
Coloration
If
you happen
to see your brand new fluorescent bulb burning with an
unusual color (we had violet), don't think that the light become
brighter
over time. Because it won't. We thought - hey let's give it a little
time. Bulbs are only 'human', they need time to warm up - then we'll
see. What we saw was nothing like that. The coloration got more and
more violet -
yes. But it never got brighter. (In hindsight, it is likely that the
internal coating was too thin, but we didn't know this back then.)
HAIRY
Quick Points |
Fluorescents
- bulbs are filled with mercury gas that is carbon-expensive
to recycle. Coated inside with
phosphor that emits light when excited. |

|
Have
to be
long enough for the phosphor surface to give off enough light so it is
packaged
in one long tube (the old
way) |
 |
or wound
up
like this "bulb"
Learn
more about Compact
Fluorescent Light Bulbs here |
Incandescents
- need a stucture that burns something in the
middle. Unfortunately, this way it pollutes inordinate amounts of heat
and light ... |
 |
To
spread light (and heat) evenly they are built with a round shape. And
if you focus light to lose less of it - making it a
reflector - turns pretty hot too. |
Photo
courtesy Wikipedia |
Anyway, do promptly what
we decided to do
eventually. Swap it for a good
one or return for a refund while you can.
Shape
comparison
This
is an area where an incandescent can hardly compare with the wild
variety of fluorescent light fixtures. Fluorescents come in many shapes
including tubes, spirals, pear shapes and possibly even spheres (I yet
to see one.) The
problem you will often face though is that the shape you find is not
the shape you look for. Retail stockist are quick to reorder them on
demand, but still very cautious to reorganize their stock light to your
incandescent vs fluorescent dilemma.
Light
output
comparison - incandescent vs
fluorescent
Brightness
Overall
they match in
final
brightness. This is because it takes some time for
fluorescents to
"lighten up" after a lower initial brightness. In the end I would give
a slight edge to incandescent lights, but this could very well be a
personal preference.
Wattage
/ Brightness comparison table
Common
household
sizes
100 |
20-27 |
1250-1750 |
Click
inside table for more information. |
Incandescent
(watt) |
Fluorescent
(watt) |
Same
light
output
range (lumen) |
40 |
7 |
400-500 |
50-60 |
10 |
500-600 |
75 |
11-15 |
600-1150 |
90 |
18 |
1150-1250 |
Track back Wattage /
Brightness comparison table:
You will want ot use this table
when:
You
don't see as well as you would
like to, but prefer to be independent and shop by yourself. The problem
for you is that Equivalent Wattage Values are often printed WAY
too small. In fact, they are often too small for just
anybody. Full stop.
You
discarded
the original package. On
the base of your new
light bulb its wattage is clearly marked, but equivalent wattage of an
incandescent bulb (or globe) is not. What a bummer ...
To get similar if
not equivalent brightness,
choose
your
compact fluorescent light bulb according to this Wattage / Brightness
Comparison
Table. Within range, you
will
get very close to equal light output.
IMPORTANT: Compact fluorescents usually gain
full brightness in about 30 seconds to a minute after you
switch them on.
Even
so, my experience is that the brightness you get then from a
fluorescent may be similar - it will still remain a
bit
shy of what I used to get from an incandescent bulb in the same range.
Update
As you can see I expanded
my initial table a bit.
In the first two columns I left the information about
similar wattage the way was noted on the
actual products. But I also
looked
up measured data on
brightness (or
light
output) calculated in lumens and
added
them in the third column. On
average, the
lower figure in that brightness range applies to a fluorescent and the
higher to an incandescent bulb. So for example a 7 Watt fluorescent
bulb tend to have an output closer to 400 lumen while the highest
output of a similar 40 Watt incandescent bulb would closer to 500 lumen.
Just one more thing:
Light output there means
the brightness you get
after
about 100 hrs of operation.
(Somewhat confusingly, this is called
initial brightness
in lighting lingo.)
Result:
The interesting thing that comes up is a confirmation
in numbers that the
similar
wattage
noted
on the products does not necessarily mean same (or similar)
brightness.
Bulb
and globe surface treatment
Incandescent
comes with a clear or frosted surface. Fluroescents are frosted. (Am
yet to see a
fluorescent other than that - and it is likely I won't.) You see,
without the
phosphor internal coating that comes across as
frosting light would be bluish
violet and ultra violet.
However, some
tinkerers use
stuff other than phosphor. Think they put
titanium dioxideoutside
the bulb and claim that the reaction of this thin surface with the
luminescent light coming from within changes the ionic content of the
air surrounding the bulbs.
They propose that these spiral bulbs purify your indoor air making you
healthier. Watch out. While there are some better products, most of the
ionised air mumbo-jumbo I found was little more than plain quackery.
Price
comparison
For
determining on your dilemma (incandescent vs fluorescent)
I should have started with this comparison. However, on the face of it
price doesn't tell much; - At least not the full story.
It is true that
fluorescents are about 3
times more expensive than using
incandescents for the same job. But is it the
same
job they do? Not
quite. The working life of incandescents is on a steady decline - at
least this is my experience. The
fluorescents we got to replace them have already worked three times
longer than the old ones ever had. But these ones are still going. So
keep buying
the old bulbs if you cannot afford the new, but
you'll likely get less and
less value for your money with incandescents.
Fluorescents on the other hand are gaining more and
more
popularity on construction jobs that are managed into facility
management and maintenance contracts. A ten story new building with 100
rooms at each level would have about 10-30 thousands new light
fixtures. These are the
real demand on the problem
incandescent vs fluorescent light bulbs. But this is an exclusive
high-end market, which is unlikely to drive pricing very much down.
Incandescent
vs Fluorescent:
The
lesser
known
things you
need to look out for.
Replacement
Two
lesser known "evils"
Replacing
everything with halogens saves energy is no more then an urban myth.
Handling:
Fluorescents
are "look don't touch" ligthts. |
The
popular belief that bright incandescents should be replaced with
halogen down-lights
- wherever possible -
doesn't hold. Where they are there for ambient room lighting use
compact
fluorescents instead. This is because to achieve the same level of
illumination you'd
need too many halogens. This in turn will use much more energy, not
less.
And
when you need bright spots, consider some
LED
bulb washers and floods
to compare effects - and possible savings -
instead of halogens.
Handling
Fluorescent
Take
extra care when
handling compact fluorescent light bulbs. Remember not to
touch the bulb with bare hands. It is a less known fact that
the grease deposited from your fingers may reduce the lifetime of your
compact fluorescent bulb or globe.
(You need to take similar care as you do with halogen light bulbs.) Use
a maintenance glove or a clean piece of cloth.
Incandescent
These
bulbs you can touch with fingers of course. But it is always wise to
clean them before use, as burnt grease is much harder to remove. As a
lot of light an incandescent bulb gives off goes into light pollution
anyway, (that is light lost to heat) occasional mishandling in this
department will not have significant effect on normal usage.
Related Articles,
Resources
Learn more
about compact fluorescent bulbs
About
long life incandescents bulbs.
Some thoughts on
LED
bulbs as flood lights
(links
open new window)
Another
comparison
is based on light output
(brightness) per watt
(also called "efficacy")
Comparison
typical
initial light
output and lifetime
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