Thread: CFL in Fridge
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Don Klipstein Don Klipstein is offline
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Default CFL in Fridge

In . com, RickH wrote:

SNIP to edit for space

The amount of energy that went into making that one CFL compared to a
regular bulb outweighs any energy you save anyway. The supply chain
for a CFL has capacitors, triacs, transistors, resistors, many kinds
of metal, phosphors, chemicals, mercury, gasses, etc. and those
complex parts have even longer supply chains,etc. The supply chain
for a light bulb has a roll of tungsten wire, some glass, some thin
aluminum or brass, a rivit, and some springy metal to hold the
filament. I'm still not convinced that CFL's are a not net energy
loss, just like ethanol is.


It's a shame that any people believe this rubbish!

How about a wild wacky extreme outside limit on amount of energy
required to turn raw earth into a CFL on a store shelf with packaging:

Go to a home center, and chances are you can find a $10 or $9.95 4-pack
of 14 or 15 watt CFLs that replace 60 watt incandescents. Also look at
Target, where the everyday price for a 4-pack of 26 watt CFLs (replace 100
watt incandescents) is about $18.

Let's assume the extreme that 100% of the $2.50 for a 15 watter or $4.50
for a 26-watter is energy.
Of course, some of that is for shareholders, some for employee wages
some of which never get spent on energy, some for wages of those
extracting raw materials and some of those wages never get spent on
energy, some goes for rent, some for insurance, some to pay engineers,
truck drivers, assembly workers, taxes along the chain, etc.

But back to what if all that cost was energy cost: At $70 per barrel,
this works out to:

..0357 barrel for a 14-15 watt CFL
..0643 barrel for a 26-watt CFL

A barrel of petroleum has 5.8 million BTU according to the 43rd edition of
the "CRC Handbook" (in the "Thermal Conversion Factors for Competitive
Fuels" table). This is about 1710 KWH.

At this rate, this works out to:

a 14-15 watt CFL takes 61 KWH to make, and
a 26 watt CFL takes 110 KWH to make,

using the wacky outside upper limit assumption that 100% of the retail
price represents energy requirement at rate of $70/bbl petroleum to make
one, package it, put it on a store shelf, and have the cashier check it
out.

Now for energy savings: Let's assume the darn thing only lasts 4,000
hours, possibly reasonable average residential life expectancy. (Rated
lifetime is in 25 degree C ambient with 3 hours of on-time per start,
usually 6,000-10,000 hours.)

The 14-15 watt CFL saves 45-46 watts, to save 180-184 KWH.

The 26 watt CFL saves 74 watts, to save 296 KWH.

Even if they only last 2,000 operating hours, their energy savings
exceed the energy requirement from raw material mining to out the retail
store door in packaging even if 100% of a lowish retail price is energy
cost at roughly past-year petroleum commodity market price.

Now, consider that electric power generation and delivery is nowhere
near 100% efficient. Figure more like 35-40%, with most of the loss being
in conversion of heat energy to mechanical energy at generating stations -
with 50% efficiency at converting heat energy to mechanical energy being
something to be very proud of, and it appears to me that most fuel-burning
generating stations achieve less.

Now, assuming 40% (optimistic) efficiency of converting fuel chemical
energy to electrical energy in your home, a 26 watt CFL only has to last
about 595 operating hours to save more energy than is in the amount of
petroleum that at $70 per barrel has same price as the per-unit price of
26 watt CFLs in a 4-pack at Target.

And besides I think the last time I changed a fridge bulb was 10 years
ago.


Better point is to argue that a fridge is not where CFLs achieve
savings. CFLs usually don't make good returns on investment in most
closets nor in most restrooms that are used mainly for short trips
(though some short-trip-frequented restrooms do well with a 4-foot
fluorescent or two).

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CFL's dont last much longer to make them compensate for their humongous
supply chains and energy in manufacture, I change blown CFL's quite
frequently in fact. And they are in the nearest landfill.


If you have them blow out a lot, then I suspect any or any combination
of the following:

1. You are using ones of brands other than Philips, Osram/Sylvania or GE,
worse still if they do not have "Energy Star" approval and are not a major
brand that a major home center chain is promoting (and the home center has
some need for its customers to be happy!).

1a. You are using a brand that I had lots of bad experiences with (mainly
before/during 2001, after which I largely stopped using that brand), and
your current experience matches my past experience. That brand is Lights
of America. However, I do suspect more likely now than was my experience
during and before 2001 is that they are/got better, otherwise I have a
hard time imagining them still being in business.

1b. You are/were using junkers/sub-junkers from dollar stores.

2. You are using CFLs where some do not do well or where most do not do
well:

2a: Recessed ceiling fixtures - those are heat hellholes. Screw base
CFLs 15 watts or more can have problems from heat there.
For that matter, I know of a series of screw base CFLs claiming
specifically that they are good for recessed ceiling fixtures - the
Philips SLS series, and then only the 15 and 20 watt ones, the
non-dimmable version of 23-watt, and not the 25-watt nor the dimmable
23-watt.
As a result, I have low expectations of any screw base CFL over 23 watts
to have good life in a recessed ceiling fixture.

Keep in mind that an incandescent lamp is about 40-50% efficient at
producing non-radiant heat (also produces quite a bit of "radiant heat"),
while a CFL is 75-80% efficient at producing non-radiant heat. CFLs have
close to all output other than visible light being non-radiant heat, while
incandescents produce plenty of infrared (which becomes heat, but mostly
after it escapes the fixture).
Also, CFLs with built-in ballasts tolerate heat less than incandescents
do.

2b: Small enclosed fixtures, ceiling fan lights, downlighting desk lamps
- also heat buildup problem areas, may overheat CFLs of wattage over 18-19
watts or so, though the best 23-watt ones (such as Philips SLS
non-dimmable) probably do well there.

3: Frequent on-off use - shortens CFL life. Worst on those that blink
during starting, second-worst to those that start instantly (whether or
not taking a minor sudden "jump" in brightness a fraction of a second to
nearly a second after starting), not as bad if there is a delay of a
fraction of a second and/or the light "fades on" over a fraction of a
second (more likely with "Big-3" brands).

With severe on-off use, cold cathode models work better - but those are
more-specialty types, mainly of wattage near or under 8 watts, and they
are less efficient than the usual hot-cathode types (though still
producing light of an incandescent of roughly 3 times their wattage).
However, they still have the same warmup issues as hot cathode ones -
the advantage of cold-cathode is lack of wear from starting.
Beware, most sub-9-watt CFLs are hot cathode. Cold cathode ones
either brag about being cold cathode, have rated life 20,000-hours-plus
and brag about lack of dimming and frequent-start problems, or both.

- Don Klipstein )