NEWS & INFO: Ozone-Friendly Fridge Breakthrough (Detailed)
Greenpeace via Jym Dyer
OZONE-FRIENDLY FRIDGE BREAKTHROUGH AS ANTARCTIC OZONE HOLE WORSENS
LONDON September 30, 1992 (GP) Close on the heels of news that
the deepest ever ozone hole is emerging over Antarctica comes
news of a breakthrough for the most ozone-destructive industrial
sector -- refrigeration.
A refrigerator which is cooled by ozone-friendly substances has
been developed by a German manufacturer in cooperation with
Greenpeace Germany, and should be in production by early next
year.
Greenpeace, after publicising the fridge to its members
in Germany, has obtained more than 70,000 (1) orders for
the fridge -- some of them large orders from retail outlets
throughout Germany.
Refrigeration is the largest single contributor to ozone
depletion world wide. Until now, chemical giants such as Du
Pont, ICI and Atochem have argued that alternatives to ozone-
destroying CFCs and HCFCs are not yet available for
refrigeration.
But the German company, DKK, has proved them wrong. Their new
fridge works on propane and butane as a coolant -- two simple
gases -- normally found in an ordinary cigarette lighter. Where
a traditional fridge uses CFC-blown foam as its insulation, this
fridge uses expanded polystyrene. The energy efficiency of the
fridge is the same as other household refrigerators.
The British Antarctic Survey released figures from Antarctica on
Monday, showing that the lowest ever values at their research
stations were recorded this week (2).
Meanwhile industrialised nations are continuing to resist
further curbs on ozone destroying emissions under the
international ozone agreement called the Montreal Protocol.
Greenpeace said today that governments were not taking the
alternatives to CFCs seriously and were likely, in November, to
take decisions at the Montreal Protocol meeting which could
prolong the ozone hole for another 20 years.
"Governments have been duped by a chemical industry which has
developed ozone destroying "alternatives" to CFCS called HCFCs,"
said Greenpeace's Bill Hare.
The chemical companies were now gearing up to produce tonnes of
HCFCs as an acceptable alternative.
"The damage likely to be caused by these new chemicals will
occur in the short term, at a time when ozone destruction will
be at its worst from the massive CFC production of the 1970s,"
he said. "We cannot afford to let this happen."
"While the ozone hole over Antarctica has deepened because of
the Mount Pinatubo eruption this year, that eruption would not
have made an ozone hole if the chlorine from these chemicals
was not present in the first place," said Mr Hare.
Greenpeace UK today published a report "Making the Right Choice
for the Ozone Layer", which provides British industry with
practical case-studies of companies which do not use ozone-
damaging chemicals such as CFCs and HCFCs.
The report shows that alternative technologies are widely
available and in commercial use.
"With these alternatives being available now, and with
scientists predicting huge increases in skin cancer, cataracts
and a breakdown in the marine food chain from ozone depletion,
there is no excuse for governments to do anything but stop the
production of these chemicals," said Mr Hare.
Notes to broadcast editors:
1. At the time of scripting the attached video, the number
of orders received by Greenpeace in Germany was 60,000.
However, that number has now climbed to more than 70,000.
2. British Antarctic Survey results published in press
release, 28 September 1992.
3. "Making the Right Choice" -- alternatives to CFCs and
HCFCs -- Greenpeace UK, phone 44-71-354 5100
4. Technical specifications and considerations
Coolant: Propane/butane mixture, approximately 20 gm
Insulation: Expanded polystyrene (not blown with CFCs)
Energy consumption: 0.67 Kw/24 hr (0.73 for DKK's equivalent
CFC12 model
Refrigerating oil: normal mineral oil
Effective capacity: 127 litres
automatic defrosting
continuous temperature control
dimension: 82.8 x 55 x 60 cm (height/width/depth) stand
and base appliance
door hangs from either side
variable units on inner door
dismantlable components, easy for recycling
price: 500 DEM for individual orders until end of
1992 (excluding shipments)
The base model will be available in late March 1993. a full
range of domestic fridges and fridge/freezers will be marketed
in the course of the following year.
To optimise the efficiency various combinations of
propane/butane mix were used until the present mixture of
approximately 50/50 was found to be the best. Further
improvements in energy efficiency were made by changing the
capillary tube to get the consumption on a par with the DKK
CFC equivalent.
Adjustment of the suction and discharge valves could further
improve the energy efficiency as could the incorporation of a
motor controller to increase the efficiency of the compressor
motor at part load.
These adjustments can be made to the first production model.
5) Company background
Since 1921 DKK Scharfenstein, based near Chemnitz in Saxony,
has been manufacturing a full range of domestic refrigerators,
freezers and compressors under the Foron trademark -- still the
leading brand in the former GDR region. Before reunification
the company produced over one million units annually of which
over 50 percent were exported, both to eastern and western
countries. After reunification the eastern market collapsed.
The dumping prices at which Foron was offered to the West in
return for hard currency could no longer be upheld. Production
decreased to 210,000 units in 1991.
The Treuhand agency -- the privatization agency responsible for
dealing with former state owned companies in East Germany --
took control of the company after reunification.
Germany's leading refrigerator producer Bosch-Siemens had
expressed an interest in purchasing DKK Scharfeinstein but then
pulled out of the deal after completing a new plant beside one
of the existing Bosch-Siemens sites in the west. At this point
the Treuhand said DKK would have to be liquidated as there was
no further interest in the company.
Weeks later Greenpeace brought together DKK Scharfenstein and
scientists from Dortmund Institute of Hygiene (who developed
the cooling system using a propane/butane mix) in June 1990
and commissioned 10 prototypes of GREENFREEZE to be delivered
in the course of September.
Greenpeace Germany has been advertising the fridge and in a
matter of weeks received 65,000 orders for it, including a
20,000 unit order from one of Germany's major mail order
companies, Neckermann. (There are now over 70,000 orders).
This campaign triggered opposition from major competitors
and charges from the association of producers of electric
appliances, ZVEI, that GREENFREEZE was less energy efficient
than "ordinary" CFC-fridges. Since GREENFREEZE has been proved
by independent results to have greater energy efficiency than
CFC refrigerators, Greenpeace Germany now calls on the
refrigerator producers to give up CFC and HFC technology in
domestic refrigeration and ask consumers to put pressure on
their traditional suppliers. 18th August 1992: Treuhand held a
press conference to announce that it would invest 5 million DEM
(approximately 1.8m Pound Sterling, 3.3m US$) for the research
and development of the propane/butane refrigerator, guaranteeing
that DKK Scharfenstein would continue its production till the
end of 1993. This guarantee means the saving of more than 400
jobs in the refrigerator production section and an additional
135 jobs in the compressor production. With this commitment and
the popularity of the company's new GREENFREEZE product it
should be easier to find a private investor before the end of
1993.
With the support of Greenpeace, DKK Scharfenstein is eager
to cooperate with refrigeration companies at all levels from
distribution to sale of components to technology transfer.
This offers especially interesting opportunities for companies
in developing countries because the use of propane/butane is
not shielded by any patents.
Richard Stead
> OZONE-FRIENDLY FRIDGE BREAKTHROUGH AS ANTARCTIC OZONE HOLE WORSENS
>
> fridge works on propane and butane as a coolant -- two simple
Ok, so it's ozone-friendly, but instead of releasing CFCs, it releases
hydrocarbons. There are several problems with this:
1) hydrocarbons like propane and butane are greenhouse gases
2) hydrocarbons, when mixed with nitrous oxides and sunlight, make ozone in
smog
3) hydrocarbons are very hazardous if they escape in your house. Your fridge
develops a small leak, the motor comes on. Boom! Goodbye home and loved
ones. And propane/butane is odorless - you won't know you have a leak.
They could try marking it with meythyl mercaptan, but how does that
affect the cooling properties of the mixture?
This does not look like an ideal solution to the problem. Maybe these problems
aren't so bad, but I'll remain skeptical until this is really proven.
--
Richard Stead
Center for Seismic Studies
Arlington, VA
st...@seismo.css.gov
John De Armond
>In article <Greenpeace.16Oct1992.2210@naughty-peahen>, j...@mica.berkeley.edu (Greenpeace via Jym Dyer) writes:
>> OZONE-FRIENDLY FRIDGE BREAKTHROUGH AS ANTARCTIC OZONE HOLE WORSENS
>>
>> But the German company, DKK, has proved them wrong. Their new
>> fridge works on propane and butane as a coolant -- two simple
Jim, Jim, Jim... Tsk, Tsk.
Breakthrough? Recent? As usual, the Econazis are a day late and a dollar
short. As as usual with both Jim and Greenwar, they get the facts
wrong.
Propane is a well known refrigerant and even has an R number. (R-290 for
those who are interested.) Propane is a pretty good direct substitute
for R-22. It does not carry oil as well so some isobutane (note that,
Jim, Not butane) is added. A non-azeotrop mix of 78% propane, 22% isobutane
is an exact replacement for R-12, the refrigerant used in some refrigerators
and car air conditioners.
George Gobble at Purdue and myself (and probably others) have been
experimenting with this mix for at least 5 years. This mix was proposed
as a substitute for R-12 in automotive use but the siren songs of the
safety nazis (more on that later) beat it down at every juncture on the
grounds of flammability. We've collaborated on another non-flammable
direct drop-in R-12 replacement that has been on the market for almost 2
years and has recently received a US patent. George presents a technical
article on this mix, known as "GHG R-12 Substitute", in the sample edition
of my magazine, available free for the asking. If you get the sample
edition, you will also read about how the air conditioning service lobby,
in an unholy alliance with some environmental groups, is trying to
get the EPA to ban these substitutes (DuPont has one too) so as to force
the conversion to R-134a, said conversion for vehicles costing anywhere from
$800 to $2000.
>Ok, so it's ozone-friendly, but instead of releasing CFCs, it releases
>hydrocarbons. There are several problems with this:
>1) hydrocarbons like propane and butane are greenhouse gases
>2) hydrocarbons, when mixed with nitrous oxides and sunlight, make ozone in
> smog
What a simplistic riot. Do a quick computation for me there, bud. Figure
out how many farts it takes to equal the hydrocarbons contained in
the 8-12 ounces of refrigerant used in a refrigerator. Sheez!
>3) hydrocarbons are very hazardous if they escape in your house. Your fridge
> develops a small leak, the motor comes on. Boom! Goodbye home and loved
> ones. And propane/butane is odorless - you won't know you have a leak.
> They could try marking it with meythyl mercaptan, but how does that
> affect the cooling properties of the mixture?
Oh bullshit. Have you no concept of perspective? A typical refrigerator
uses 8-12 ounces of refrigerant. Do you have a feel for what a tiny
quantity that is? Have you ever figured out how much butane propellant
is in a typical aerosol can? Propellant is typically listed as a
percentage on the side of an aerosol can so it is easy enough to compute.
And do you quake in your shoes at the thought of having a can of butane
cigarette lighter fuel in your house? The cans of butane I buy to
refuel my butane soldering iron contain 10 ounces in a paper-thin
steel can. If you fear a few ounces of flammable refrigerant sealed
inside a thick hermetic system, you have to be terrified of aerosol
cans or lighter butane. When was the last time you heard of a refrigerator
mysteriously springing a leak without provocation? When was the
last time you heard of a aerosol can being punctured from being dropped
on a sharp object? Or rusting through? Or flat just starting to leak?
More to the direct point of the flammability issue. The non-flammability
of CFC-type refrigeratants is a myth. A CFC by itself is fairly hard to
ignite. The refrigerant never exists in the absence of oil in a refrigeration
system. A refrigerant mixed with oil mist, as always happens during a
leak of any consequence, is a whole 'nuther matter. We've demonstrated,
and George made a video tape of, the equivalent flammability of
R-12 and oil vs propane and oil. In the video, the burning jet from
the R-12 container is indistinguishable from that of the propane.
This video has surprised the experts in the field so surprise from the
layman is expected.
>This does not look like an ideal solution to the problem. Maybe these problems
>aren't so bad, but I'll remain skeptical until this is really proven.
You're right here. "Ideal" would be zero cost, zero environmental effect,
zero risk. Not achievable except in the minds of some safety/econazis.
We can, however approximate "ideal" sufficient for refrigeration
purposes.
John
--
John De Armond, WD4OQC |Interested in high performance mobility?
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E. Michael Smith
>In article <Greenpeace.16Oct1992.2210@naughty-peahen>, j...@mica.berkeley.edu (Greenpeace via Jym Dyer) writes:
>> OZONE-FRIENDLY FRIDGE BREAKTHROUGH AS ANTARCTIC OZONE HOLE WORSENS
>>
>> But the German company, DKK, has proved them wrong. Their new
>> fridge works on propane and butane as a coolant -- two simple
>
>Ok, so it's ozone-friendly, but instead of releasing CFCs, it releases
>hydrocarbons. There are several problems with this:
>3) hydrocarbons are very hazardous if they escape in your house. Your fridge
> develops a small leak, the motor comes on. Boom! Goodbye home and loved
> ones. And propane/butane is odorless - you won't know you have a leak.
> They could try marking it with meythyl mercaptan, but how does that
> affect the cooling properties of the mixture?
>
>This does not look like an ideal solution to the problem. Maybe these problems
>aren't so bad, but I'll remain skeptical until this is really proven.
I think this was covered a while back... the quantity of HC is so
small as to not be particularly problematic (that is, about the
same risk as a lighter refill can, a commonly accepted risk.)
Also, the small ppm of mercaptan needed to mark should have little to
no effect on the refrigeration properties.
--
E. Michael Smith e...@apple.COM
'Whatever you can do, or dream you can, begin it. Boldness has
genius, power and magic in it.' - Goethe
I am not responsible nor is anyone else. Everything is disclaimed.
Richard Stead
> st...@skadi.CSS.GOV (Richard Stead) writes:
> >Ok, so it's ozone-friendly, but instead of releasing CFCs, it releases
> >hydrocarbons. There are several problems with this:
> >1) hydrocarbons like propane and butane are greenhouse gases
> >2) hydrocarbons, when mixed with nitrous oxides and sunlight, make ozone in
> > smog
>
> What a simplistic riot. Do a quick computation for me there, bud. Figure
> out how many farts it takes to equal the hydrocarbons contained in
> the 8-12 ounces of refrigerant used in a refrigerator. Sheez!
I stand corrected, I did not realize that it was that small an amount.
As for the requested computation, if you assume an average fart is about
1/2 a liter gas volume (I imagine more than that could get quite uncomfortable),
then 1000 farts= 12ounces propane (carbon equivalent). Quite a few farts, but
not incomprehensible. Still, farts are not 100% methane, so there's another
fudge 8-) factor involved.
> >3) hydrocarbons are very hazardous if they escape in your house. Your fridge
> > develops a small leak, the motor comes on. Boom! Goodbye home and loved
> > ones. And propane/butane is odorless - you won't know you have a leak.
> > They could try marking it with meythyl mercaptan, but how does that
> > affect the cooling properties of the mixture?
>
> Oh bullshit. Have you no concept of perspective? A typical refrigerator
> uses 8-12 ounces of refrigerant. Do you have a feel for what a tiny
> quantity that is? Have you ever figured out how much butane propellant
> is in a typical aerosol can? Propellant is typically listed as a
No. How much is there? But on another note, I never buy _ANY_ aerosol.
I think they're all environmentally unsound in that no matter what you do,
all of the propoellant and a lot of the other material just end up in the
air. Anyway, the SCAQMD (the quasi-governmental body that has far-reaching
powers to regulate air quality in L.A.) has considered hydrocarbon propellants
to be a significant contributor to smog. Thus, at least one "expert" body
would agree that hydrocarbon propellants are a hazard. I don't know if they
would likewise consider hydrocarbon refridgeration a problem.
> And do you quake in your shoes at the thought of having a can of butane
> cigarette lighter fuel in your house? The cans of butane I buy to
I would never allow that - heck, I keep the white gas for the backpack stove
isolated and outside in a well-ventilated storage area.
> inside a thick hermetic system, you have to be terrified of aerosol
> cans or lighter butane. When was the last time you heard of a refrigerator
Ever seen what the product testers can make a butane lighter do? But, you're
right, I'm not scared of the lighters themselves.
> mysteriously springing a leak without provocation? When was the
But that's the whole problem! If they never leaked, CFC's wouldn't be a problem
either! However, for the fridges that invariably get dumped in public areas,
I don't have a good feeling about when the kids would come to fool around with
one that happened to be propane cooled.
> last time you heard of a aerosol can being punctured from being dropped
> on a sharp object? Or rusting through? Or flat just starting to leak?
When I was a kid, I had a can of spray paint burst when I dropped it. What a
mess. On another occasion, I saw the results of a can of spray lubricant
that disgorged itself through a hole in the bottom in the back of a friend's
car. So even that does happen. Yet we know that cooling systems leak -
that's why so many people have to get their auto air-conditioners recharged
every year or two. I guess a thick hermetic system with lots of joints and
O rings and moving parts just leaks easier than a simple spray can.
> More to the direct point of the flammability issue. The non-flammability
> of CFC-type refrigeratants is a myth. A CFC by itself is fairly hard to
> ignite. The refrigerant never exists in the absence of oil in a refrigeration
> system. A refrigerant mixed with oil mist, as always happens during a
> leak of any consequence, is a whole 'nuther matter. We've demonstrated,
> and George made a video tape of, the equivalent flammability of
> R-12 and oil vs propane and oil. In the video, the burning jet from
> the R-12 container is indistinguishable from that of the propane.
> This video has surprised the experts in the field so surprise from the
> layman is expected.
Ok, I'm surprised. I have a question - was the fridge on, or had it been
off for awhile? Running the fridge probably generates the mist, while an idle
device may not? I think both the safety of the running product and the stored
(or dumped) product ought to be addressed. Still, if it didn't ignite as
a jet, I doubt that oil mist would stay suspended well enough to explode
in a room. 12 ounces of propane would occupy a kitchen of 12 feet x 12 feet
x 8 feet at a partial pressure of 0.005 atmospheres. That's a factor of
4 too small to explode, but damn close for comfort.
> We can, however approximate "ideal" sufficient for refrigeration
> purposes.
I agree, but I'mm still not thoroughly convinced. I'm not trying to be
negative, just registering some honest scientific skepticism.
Carl J Lydick
>mysteriously springing a leak without provocation?
Do you mean that much of the refrigerator service industry is a fraud?
--------------------------------------------------------------------------------
Carl J Lydick | INTERnet: CA...@SOL1.GPS.CALTECH.EDU | NSI/HEPnet: SOL1::CARL
Disclaimer: Hey, I understand VAXen and VMS. That's what I get paid for. My
understanding of astronomy is purely at the amateur level (or below). So
unless what I'm saying is directly related to VAX/VMS, don't hold me or my
organization responsible for it. If it IS related to VAX/VMS, you can try to
hold me responsible for it, but my organization had nothing to do with it.
Paul Houle
>hydrocarbons. There are several problems with this:
>1) hydrocarbons like propane and butane are greenhouse gases
>2) hydrocarbons, when mixed with nitrous oxides and sunlight, make ozone in
> smog
>3) hydrocarbons are very hazardous if they escape in your house. Your fridge
> develops a small leak, the motor comes on. Boom! Goodbye home and loved
> ones. And propane/butane is odorless - you won't know you have a leak.
> They could try marking it with meythyl mercaptan, but how does that
> affect the cooling properties of the mixture?
From what I remember, the total amount of hydrocarbons in this
refigerator is on the order of ~30 grams, which is comparable to that
in a cigarette lighter. As such, the total amount that they would leak
would be rather small at best, and they would pose a relatively minor
environmental issue compared to CFCs. If the amount is small enough,
the refigerator at worst could be a fire hazard; a cigarette lighter
can explode and kill the person who is holding it, but the worst that
would happen if it were mounted inside a refigerator would be serious
damage to the refrigerator.
Since methyl mercapitan is detectable in ppb quantities, the
amount that would be needed to serve as a tracer would be rather small
and probably wouldn't have any effect on the cooling properties of
the hydrocarbon mixture.
--
John De Armond
>In article <08s...@dixie.com>, j...@dixie.com (John De Armond) writes:
>>When was the last time you heard of a refrigerator
>>mysteriously springing a leak without provocation?
>Do you mean that much of the refrigerator service industry is a fraud?
I've sat here for several minutes trying to figure out how your question
related to my statement. I can't figure a relationship and have to
assume you were simply making noise. How you related fraud into this
discussion is beyond me?
I'll repeat the question. When was the last time you heard of a refrigerator
springing a leak without provocation? I'll tell you what my answer is.
Almost never. In the 4 years I owned and operated a refrigeration
service company, I could count on one hand the times I found a hermetic
system that needed charging. I'd bet those were deficient from
the factory. The reason is simple. The system, as its name indicates,
is hermetically sealed. Until the owner provokes a leak, typically
with a knife or ice pick, there is no place for the freon to leak from.
John De Armond
>But that's the whole problem! If they never leaked, CFC's wouldn't be a problem
>either! However, for the fridges that invariably get dumped in public areas,
>I don't have a good feeling about when the kids would come to fool around with
>one that happened to be propane cooled.
Ok, from the top. How many 'friges have you ever seen dumped? Three or
four? A dozen? Two dozen? In my case I'd say perhaps a couple of
dozen. Now how many million refrigerators are in use? How many
do you suppose get fixed and/or recycled? Hint: Most of 'em.
Now, what difference in "bad feelings" would you have between kids
fooling around with propane refrigerant and those same kids fooling
around with a can of spray paint, a propane torch or a can of gas?
Particularly when this 'frige has been dumped out in some open
area?
>Yet we know that cooling systems leak -
>that's why so many people have to get their auto air-conditioners recharged
>every year or two.
Automobile A/C have nothing to do with this thread and are, of course,
completely different animals. We're talking about hermetically
sealed refrigeration systems as installed in refrigerators, freezers and
so on. Hermetic systems do NOT leak unless breached. There is simply
no way for it to happen. Example: I have a 1929 GE Monitor Top
refrigerator. Still running and still on the original charge. Of
Sulfur Dioxide.
>I guess a thick hermetic system with lots of joints and
>O rings and moving parts just leaks easier than a simple spray can.
A car system is not hermetically sealed.
>Ok, I'm surprised. I have a question - was the fridge on, or had it been
>off for awhile? Running the fridge probably generates the mist, while an idle
>device may not? I think both the safety of the running product and the stored
>(or dumped) product ought to be addressed.
Nope. Doesn't matter. Oil and freon are infinitely miscible and always
flow together. The mist is formed when the pressure is suddenly reduced
as the mix escapes the system and the dissolved freon expands, breaking
the rest of the mix up into little droplets - an aerosol. This is
EXACTLY how an aerosol can work. Is it not obvious to you that
the contents of an aerosol can do not form a mist until sprayed?
The sloshing should give you a hint.
>Still, if it didn't ignite as
>a jet, I doubt that oil mist would stay suspended well enough to explode
>in a room.
Actually the oil mist stays suspended quite well because the boiling
effect makes such small particles.
>12 ounces of propane would occupy a kitchen of 12 feet x 12 feet
>x 8 feet at a partial pressure of 0.005 atmospheres. That's a factor of
>4 too small to explode, but damn close for comfort.
I have no idea where you get your numbers but let me ask this. Does
a safety factor of 4 really frighten you? Do you have a concept of
what that means?
>> We can, however approximate "ideal" sufficient for refrigeration
>> purposes.
>I agree, but I'mm still not thoroughly convinced. I'm not trying to be
>negative, just registering some honest scientific skepticism.
Sorry, Richard, but no, this is not scientific skepticism. It is factless
fearmongoring. If you really do fear things like this, your life
must be terrifying, what with all the other "dangerous" things like
electricity only a wrong move away.
George Goble
>> More to the direct point of the flammability issue. The non-flammability
>> of CFC-type refrigeratants is a myth. A CFC by itself is fairly hard to
>> ignite. The refrigerant never exists in the absence of oil in a refrigeration
>> system. A refrigerant mixed with oil mist, as always happens during a
>> leak of any consequence, is a whole 'nuther matter. We've demonstrated,
>> and George made a video tape of, the equivalent flammability of
>> R-12 and oil vs propane and oil. In the video, the burning jet from
>> the R-12 container is indistinguishable from that of the propane.
>> This video has surprised the experts in the field so surprise from the
>> layman is expected.
>
>Ok, I'm surprised. I have a question - was the fridge on, or had it been
>off for awhile? Running the fridge probably generates the mist, while an idle
>device may not? I think both the safety of the running product and the stored
>(or dumped) product ought to be addressed. Still, if it didn't ignite as
>a jet, I doubt that oil mist would stay suspended well enough to explode
>in a room. 12 ounces of propane would occupy a kitchen of 12 feet x 12 feet
>x 8 feet at a partial pressure of 0.005 atmospheres. That's a factor of
>4 too small to explode, but damn close for comfort.
>
A car could have about 20 oz total.. About half the weight is needed of the
Freon-12 it replaces. The flammability tests I did on R-12, were to
put 3lbs + 10% 525 viscosity mineral oil (typical charge for an auto
A/C) into a "dial-a-charge" measuring cylinder. Opened 'er up and lit
it.. made a 12 ft jet of fire, similar to lighting WD-40 spray can.
This was back when it was still legal to vent CFCs. If not ignited,
the "oil fog" hangs around for 10-15 mins sometimes. It would be similar
to flour dust in a grain mill, etc. I know refrigeration who caused
explosions (outside and rooftop units) when they lit up their torch
too quickly after blowing off the refrigerant charge. It was the
oil mist which exploded. Fridges use 150 viscosity oil instead of 525 as
cars do. 150 makes it even more "flammable".
WHen the Freon crunch hits in a year or so, and people forced with
a $1000-$1800 "retrofit" to R-134a, wonder how many will just sweat?
Wonder if anybody will go to their camping store and get a 6oz can
of isobutane fuel and go to the hardware store for 14oz of propane
and charge that into their car A/C? That would be approx the correct
charge for a 40oz R-12 system and the mix would be 30% isobutane,
70% propane which might work.
--ghg
Gary Coffman
>In article <51...@seismo.CSS.GOV> st...@skadi.CSS.GOV (Richard Stead) writes:
>>In article <Greenpeace.16Oct1992.2210@naughty-peahen>, j...@mica.berkeley.edu (Greenpeace via Jym Dyer) writes:
>>> But the German company, DKK, has proved them wrong. Their new
>>> fridge works on propane and butane as a coolant -- two simple
>>
>>Ok, so it's ozone-friendly, but instead of releasing CFCs, it releases
>>hydrocarbons. There are several problems with this:
>
>small as to not be particularly problematic (that is, about the
>same risk as a lighter refill can, a commonly accepted risk.)
Naturally, the same thing was said about CFCs when they were introduced.
Each fridge only uses a small amount, so the leakage is negligble. The
problem becomes one of scale again. BTW propane/isobutane mixes used
as refrigerants are nothing new. They, along with ammonia, were widely
used before CFCs were developed. Since ammonia is toxic, and propane
flamable, CFCs were embraced by the industry as a *safe* alternative
to these chemicals. It's really no big deal to go back to these older
methods, but you have to assume the risks they pose that caused them
to be replaced in the first place. There is no free lunch.
Gary
Richard Stead
[Nasty response full of ad-hominem attacks, personal crap and non-seqitors
deleted.]
Bub, I politely asked some honest scientific questions in a discussion group
that's SCI.energy. I can't trust the data in your non-scientific response,
because I have learned that people who grind political axes like that just
plain lie. Hell, I'm not even a liberal. But I'll stack my scientific
credentials against yours any day. Take your crap and pack it off to
talk.politics or something.
FRANK NEY
Hey John:
Why don't we quit with the 'might' and figure out precisely what we
have to do to replace R-12 in our vehicles? Is this going to be a
trial-and-error-mostly-error or is there some way to get close
theoretically and then fine-tune the mix empirically?
And what kind of jury-rig can the weekend mechanic come up with using
existing auto store equipment and tools?
Frank Ney N4ZHG EMT-A LPVa NRA ILA GOA CCRTKBA "M-O-U-S-E"
Commandant and Acting President, Northern Virginia Free Militia
Send e-mail for an application and more information
----------------------------------------------------------------
Democracy is based on the theory that the common people know
what they want and deserve to get it -- GOOD AND HARD!!!
--
The Next Challenge - Public Access Unix in Northern Va. - Washington D.C.
703-803-0391 To log in for trial and account info.
Kershner Wyatt
>In article <51...@seismo.CSS.GOV> st...@skadi.CSS.GOV (Richard Stead) writes:
>> ones. And propane/butane is odorless - you won't know you have a leak.
>> They could try marking it with meythyl mercaptan, but how does that
>> affect the cooling properties of the mixture?
If you're talking about that foul smelling stuff added to bottled gas, I don't
imagine it takes enough to matter, it certainly doesn't affect its combustion
abilities.
--
Kershner Wyatt
kwy...@ccscola.ColumbiaSC.ncr.com
My opinions are my own and aren't necessarily my employer's.
John De Armond
>BTW propane/isobutane mixes used
>as refrigerants are nothing new. They, along with ammonia, were widely
>used before CFCs were developed. Since ammonia is toxic, and propane
>flamable, CFCs were embraced by the industry as a *safe* alternative
>to these chemicals. It's really no big deal to go back to these older
>methods, but you have to assume the risks they pose that caused them
>to be replaced in the first place. There is no free lunch.
Ammonia, Sulfur Dioxide and Methyl Chloride were the predominant refrigerants
used before CFCs according to my 1940 Coyne Refrigeration Handbook. Back
then the hazards were real and severe. Flooded evaporators were the norm,
as were open shaft (non-hermetic) compressors. A household system such as my
GE Monitor Top might contain literally gallons of refrigerant.
Several things must be known in order to assess the risk. In most
refrigerators up to the late 60s, the evaporator was either a structural
component or was exposed on the surface of the interior. In my MonitorTop,
the evaporator assembly is a massive cast aluminum assembly. It forms
the "freezer" part of the refrigerator. Later designs pressed the evaporator
coils into sheets of metal that formed either the freezer or lined the
walls of same. None were frost-free. The greatest risk, and the repairman's
favorite person, was the housewife wielding an ice pick while defrosting.
Even the old MonitorTop suffered from that risk. My handbook outlines in
some detail the art of aluminum soldering, an art perfected decades before
these shysters at flea markets selling miracle rods came along.
Let's compare that to today's refrigerator. The refrigerant system is
totally hermetically sealed. Physical damage and a very rare compressor
lead penetration burnthrough are the only real threats to the system's
integrety. The evaporator is typically buried in the bottom or the back
and cold air is circulated by fan. There is no defrosting and indeed,
the owner could not do so without disassembling the unit. The amount of
refrigerant involved might mostly fill a coffee cup. Given these design
features, I'd have no problem at all even with sulfur dioxide as the
refrigerant. I wouldn't even give a second thought to something
as innocuous as propane/isobutane.
I wonder how many people would recoil in horror at a propane refrigerant
routinely use a gas stove in their kitchen. A device lacking any
safety cutoff and connected to an unlimited supply of gas. Hmmm.
Kershner Wyatt
>st...@skadi.CSS.GOV (Richard Stead) writes:
>>that's why so many people have to get their auto air-conditioners recharged
>>every year or two.
People have to get their A/C recharged because they don't have the common
sense to either read the owners' manual or listen. An A/C will lose very
little Freon if it is operated routinely, keeping the seals in good shape.
Yes, eventually it will hit a point at which a recharge is needed, but with
a little effort that can be avoided for years. What's routinely? Once
a week for a few minutes.
It's that easy to keep out of the repair shop which is something I definitely
want to do with the new recovery systems they're using.
E. Michael Smith
Two things... first, the problem with CFCs is their persistence into
the upper atmosphere. That is not the problem with HCs which are
oxidized quickly in the lower atmosphere. (making photochemical smog ...)
The problem with HCs is their flamability. But modern 'friges use
far less refrigerant than the older ones... so it really ISN'T a
case of assuming the same risks they posed in the past. The quantity
of refrigerant reduction changes the quality of the risk! (i.e. if
the quantity is small enough to fall below the flamability limits
when diffused into a typical kitchen, the explosive destruction of
the house is no longer the risk ...)
Quantity has a quality all its own ...
John De Armond
>In article <4=vp...@dixie.com>, j...@dixie.com (John De Armond) writes:
>[Nasty response full of ad-hominem attacks, personal crap and non-seqitors
>deleted.]
>Bub, I politely asked some honest scientific questions in a discussion group
>that's SCI.energy. I can't trust the data in your non-scientific response,
>because I have learned that people who grind political axes like that just
>plain lie. Hell, I'm not even a liberal. But I'll stack my scientific
>credentials against yours any day. Take your crap and pack it off to
>talk.politics or something.
Rich, you're pulling a Clinton. Let's take a look at what you said. Your
first post on the subject:
---
In article <Greenpeace.16Oct1992.2210@naughty-peahen>, j...@mica.berkeley.edu (Greenpeace via Jym Dyer) writes:
> OZONE-FRIENDLY FRIDGE BREAKTHROUGH AS ANTARCTIC OZONE HOLE WORSENS
>
> But the German company, DKK, has proved them wrong. Their new
> fridge works on propane and butane as a coolant -- two simple
Ok, so it's ozone-friendly, but instead of releasing CFCs, it releases
hydrocarbons. There are several problems with this:
1) hydrocarbons like propane and butane are greenhouse gases
2) hydrocarbons, when mixed with nitrous oxides and sunlight, make ozone in
smog
3) hydrocarbons are very hazardous if they escape in your house. Your fridge
develops a small leak, the motor comes on. Boom! Goodbye home and loved
ones. And propane/butane is odorless - you won't know you have a leak.
They could try marking it with meythyl mercaptan, but how does that
affect the cooling properties of the mixture?
This does not look like an ideal solution to the problem. Maybe these problems
aren't so bad, but I'll remain skeptical until this is really proven.
-------
Seems like the only question you asked was regarding mercaptan. The rest
of your post consisted of assertions that can charitably be described as
assertive statements that pander to people's fears. You either had no
concept of the amount of materials involved or you intentionally overblew
the risks for reasons unknown. The actual risk is even smaller than I
posted because as GHG has noted, I neglected to compensate the refrigerant
masses for the difference in densities.
That your delicate ego got bruised by my rebuttal demonstrates the level
of your "credentials". You've obviously never presented a paper before
your peers or else your skin would be thickened to the point that such
minor jabs would bounce right off. You're simply a government bureaucrat
masquerading as a scientist while sucking at the Uncle's hind tit who
screamed his head off when poked. Now we know.
James W. Swonger
lines. Just a datapoint. Pretty stupid to use plain steel in a high pressure
condensation-prone application I think. But then things might not break if
they were designed right....
Since I play with solvents, acetylene and propane several nights a week
the 1:1E6 odds of one more propane leak fail to worry me. However, I'm
also just the sort of guy who climbs on ladders and steps into the bathtub
without performing a risk analysis. Amazing that I've survived, true. I do
fear that the odds will catch up with me in the next 50 years or so.
For my next feat of bravado, I will Drive My Car!
--
##########################################################################
#Irresponsible rantings of the author alone. Any resemblance to persons #
#living or dead then yer bummin. May cause drowsiness. Alcohol may inten-#
#sify this effect. Pay no attention to the man behind the curtain. Billy!#
William Stoffel
letting John DA, etal, take the flack for trying to add a little perspective
to this so-called release;
In sci.energy, j...@mica.berkeley.edu (Greenpeace via Jym Dyer) writes:
>[Greenpeace Press Release from Greenbase -- Redistribute Freely]
>
>OZONE-FRIENDLY FRIDGE BREAKTHROUGH AS ANTARCTIC OZONE HOLE WORSENS
>
>LONDON September 30, 1992 (GP) Close on the heels of news that
>the deepest ever ozone hole is emerging over Antarctica comes
>news of a breakthrough for the most ozone-destructive industrial
>sector -- refrigeration.
I'm not sure that there is universal scientific agreement on this statement,
but that is easily a topic for a separate flame war of its own.
>A refrigerator which is cooled by ozone-friendly substances has
>been developed by a German manufacturer in cooperation with
>Greenpeace Germany, and should be in production by early next
>year.
[para. on impressive pre-production sales figures deleted]
>Refrigeration is the largest single contributor to ozone
>depletion world wide. Until now, chemical giants such as Du
>Pont, ICI and Atochem have argued that alternatives to ozone-
>destroying CFCs and HCFCs are not yet available for
>refrigeration.
I think this statement may, at best, be based on information taken somewhat
out of context. First, calling both CFCs and HCHC's equal in ozone destruction
is a gross generalization. The most familiar CFC for most of us is CFC-12
(aka R-12, aka freon 12). It has a ozone depletion potential of 1.0
and is definitely a bad actor (if you agree with the basic theory of
course). I don't know about the other companies, but DuPont already
produces and markets HFC-134a (trade name Savon or something like that).
It is already appearing in some '93 vehicles. To the best of my knowledge,
DuPont at least, has always agreed to comply with phasing out production
of CFC-12 in accordance with the Montreal Protocol. I'm not familiar
with the status of the other CFC-12 candidates or the other chemical
companies, but this is at least one fairly major exception to the above
generalization.
The most familiar HCFC for most of us is HCFC-22 (aka R-22, aka freon
22). It is used in most residential central AC and heat pump systems.
It has an ozone depletion potential of 0.05 and should certainly not
be considered as equally destructive as CFC-12. This is not just my
opinion either, the folks at the first Montreal Protocol apparently
agreed by not targeting it for replacement in the same time frame as
CFC-12.
>But the German company, DKK, has proved them wrong. Their new
>fridge works on propane and butane as a coolant -- two simple
>gases -- normally found in an ordinary cigarette lighter. Where
>a traditional fridge uses CFC-blown foam as its insulation, this
>fridge uses expanded polystyrene. The energy efficiency of the
>fridge is the same as other household refrigerators.
I sincerely wish them commercial success with this product. Such refrigerants
would not be acceptable for use in shipboard systems, but I'm not aware
of any insurmountable obstacles to successful use in commercial sealed
systems.
>The British Antarctic Survey released figures from Antarctica on
>Monday, showing that the lowest ever values at their research
>stations were recorded this week (2).
>Meanwhile industrialised nations are continuing to resist
>further curbs on ozone destroying emissions under the
>international ozone agreement called the Montreal Protocol.
OK, this is where things start to fall apart. Last I heard the U.S.
was actually going to ACCELERATE the ban on CFC production. The vehicle
for doing this was the Clean Air Act (Title VI, Section 608). Sorry,
I'm not sure of the current status (call you congesscritter and check),
but this hardly sounds like "continuing resistance" to me. I don't know
about the other signators to the Protocol, but I'd be surprised if they'd
let the U.S. be the only hero tho.
>Greenpeace said today that governments were not taking the
>alternatives to CFCs seriously and were likely, in November, to
>take decisions at the Montreal Protocol meeting which could
>prolong the ozone hole for another 20 years.
I'd love to see the basis for this conclusion. From where I sit the
U.S. seems to be taking it very seriously. What "decisions" are Greenpeace
refering to?
>"Governments have been duped by a chemical industry which has
>developed ozone destroying "alternatives" to CFCS called HCFCs,"
>said Greenpeace's Bill Hare.
sheesh! I hope nobody pays for this stuff. HCFC's and CFC's have both
existed for a long time. They are just different refrigerants used in
different applications. At least some of the HCFC's happen to also have
lower ozone depletion potentials, but they were not "developed" for
this purpose. There may be some "duping" going on here, but it's not
by the chemical industry. In fact, at least one CFC-12 alternative
WHICH IS ALREADY ON THE MARKET, is not a HCFC at all. [C2H2F4, as in
no chlorine].
>The chemical companies were now gearing up to produce tonnes of
>HCFCs as an acceptable alternative.
As far as I know, some HCFC's may still be acceptable alternatives.
I think the folks at the Montreal Protocol should deside if they aren't,
not G Greenpeace. In the meantime, many other alternatives are also
being investigated.
>"The damage likely to be caused by these new chemicals will
>occur in the short term, at a time when ozone destruction will
>be at its worst from the massive CFC production of the 1970s,"
>he said. "We cannot afford to let this happen."
Absolute nonsense. See above comments.
The original article ranted on for several more pages. As near as I
can tell, the article is suggesting that one, and only one, potential
CFC alternative for refrigerators will completely solve the ozone depletion
problem, and that any government or company which even suggests something
different is involved in some secret plot to destroy the world.
While the blend they advocate may indeed work in small sealed systems,
no data is provided to suggest it will work in a system with mechanical
seals (e.g. autos), and it certainly will not operate in systems designed
to different pressures, temps, etc.
Bill Stoffel
sto...@oasys.dt.navy.mil
[all standard disclaimers apply]
Hank Roberts
Re the damage potential of HCFCs versus CFCs -- I recall reading that
HCFCs, while they do less damage per year, last many years longer in the
stratosphere. The tradeoff is a "big" ozone hole "briefly" from
CFCs, versus a "less big" ozone hole "longer" from the alternative HCFCs.
There are also HF compounds being suggested which, lacking chlorine, appear
not to be contributors to the ozone catalysis.
No cites handy, but I'll see what I can dig up.
William Stoffel
>Re the damage potential of HCFCs versus CFCs -- I recall reading that
>HCFCs, while they do less damage per year, last many years longer in the
>stratosphere. The tradeoff is a "big" ozone hole "briefly" from
>CFCs, versus a "less big" ozone hole "longer" from the alternative HCFCs.
This may be true in some (many?) cases. I only have data for the relatively
common CFC-12 (autos etal) and HCFC-22 (residential central AC/heat
pumps etal).
CFC-12 HCFC-22
Ozone depletion potential 1.0 0.05
Atmospheric lifetime (years) 111 20
These figures have been in common usage for a while and I don't have
an official reference. They should agree with the data used by the first
Montreal Protocol. I'll try to identify the original source and post
same.
>There are also HF compounds being suggested which, lacking chlorine, appear
>not to be contributors to the ozone catalysis.
This is true. There are a number of chlorine free refrigerants being
considered. At least one, a replacement for CFC-12 called HFC-134a,
is already on the market. It is already starting to appear in some '93
autos.
Regards - Bill
__________________________________________________________________________
Bill Stoffel | CARDEROCKDIV, NSWC |First things first! |
sto...@oasys.dt.navy.mil | Code 2759 | (But not necessarily in|
(410) 267-3825 | Annapolis, MD 21402 |that order) - The Doctor|
_________________________________________________|________________________|
Hank Roberts
>common CFC-12 (autos etal) and HCFC-22 (residential central AC/heat
>pumps etal).
> CFC-12 HCFC-22
>Ozone depletion potential 1.0 0.05
>Atmospheric lifetime (years) 111 20
>These figures have been in common usage for a while and I don't have
>an official reference. They should agree with the data used by the first
>Montreal Protocol. I'll try to identify the original source and post
>same.
>>There are also HF compounds being suggested which, lacking chlorine, appear
>>not to be contributors to the ozone catalysis.
>This is true. There are a number of chlorine free refrigerants being
>considered. At least one, a replacement for CFC-12 called HFC-134a,
>is already on the market. It is already starting to appear in some '93
>autos.
Thank you! I had the lifetimes of the chemicals backwards, you're correct.
I found the same info in New Scientist 1 Sept 1988 -- with a bit of a
different slant. They were warning in New Scientist that the use of CFC-22
was being put forth as "ozone-safe" but that research had just then shown
that, while most of it does get broken down in the troposphere, some of it
does survive to the stratosphere.
And that causes a problem because, since [H]CFC-22 is more rapidly broken
down, it dumps its chlorine faster. So rather than producing a prolonged
ozone deficit like the more stable CFCs, it is expected to produce its
damage early on, in the 2000-2040 AD time scale -- adding to the peak
problem.
Spooky. At the time, 1988, CFC-22 was not included in the Montreal Protocol
and apprently DuPont believed that it was "safe" and research had just begun
to come in showing otherwise. I'd appreciate any updated info, thanks!
Richard Stead
> st...@skadi.CSS.GOV (Richard Stead) writes:
>
> >In article <4=vp...@dixie.com>, j...@dixie.com (John De Armond) writes:
> >[Nasty response full of ad-hominem attacks, personal crap and non-seqitors
> >deleted.]
>
> >Bub, I politely asked some honest scientific questions in a discussion group
> >that's SCI.energy. I can't trust the data in your non-scientific response,
> >because I have learned that people who grind political axes like that just
> >plain lie. Hell, I'm not even a liberal. But I'll stack my scientific
> >credentials against yours any day. Take your crap and pack it off to
> >talk.politics or something.
>
> Rich, you're pulling a Clinton. Let's take a look at what you said. Your
> first post on the subject:
The guy still thinks thinks I'm a liberal.
Also, he decides to go back to my first post on the subject,
rather than the post he responded to above.
> Ok, so it's ozone-friendly, but instead of releasing CFCs, it releases
> hydrocarbons. There are several problems with this:
> 1) hydrocarbons like propane and butane are greenhouse gases
> 2) hydrocarbons, when mixed with nitrous oxides and sunlight, make ozone in
> smog
> 3) hydrocarbons are very hazardous if they escape in your house. Your fridge
> develops a small leak, the motor comes on. Boom! Goodbye home and loved
> ones. And propane/butane is odorless - you won't know you have a leak.
> They could try marking it with meythyl mercaptan, but how does that
> affect the cooling properties of the mixture?
>
> This does not look like an ideal solution to the problem. Maybe these problems
> aren't so bad, but I'll remain skeptical until this is really proven.
> -------
>
> Seems like the only question you asked was regarding mercaptan. The rest
This is a naive understanding of both the language and the nature of
scientific question and response. True, my first post does not ask much
(the post that generated his first garbage attack was more interrogative),
but the last statement I originally made, quoted again by you above,
would be understood by any scientist as a request for more information
and further proof. English has never required a '?' for forming a
question, it is just one style of questioning. I would have thought
a journalist might know this.
> assertive statements that pander to people's fears. You either had no
> concept of the amount of materials involved or you intentionally overblew
> the risks for reasons unknown. The actual risk is even smaller than I
> posted because as GHG has noted, I neglected to compensate the refrigerant
> masses for the difference in densities.
I freely admit that I did not know the masses of material involved.
Clearly, my knowledge of refridgeration requires updating, not surprizing,
given it is not a specialty of mine. I imagined masses closer to
about 500 grams. The amounts since posted by polite and informative
sources clears that up, but a small explosion hazard still exists.
I have since been informed by other polite sources that fire and
explosion hazard is not significantly different for CFC systems.
Of course, the journalist has missed the point - if leakage of
hydrocarbons from a fridge is insignificant, both in the chance
that it might occur, and the total amount even if it did, then why
are we talking about replacing CFCs in the first place? As has been
pointed out, car air conditioners contain far more CFCs, and are more likely
to leak. If there is such a large difference, then why doesn't
fixing solely the cars solve the problem? (As a note to the journalist -
these are rhetorical questions - they have a question mark, but
a question is not really being asked).
> That your delicate ego got bruised by my rebuttal demonstrates the level
He thinks my ego was bruised, simply because I prefer a somewhat higher
standard of nettiquette than his posts are demonstrating.
> of your "credentials". You've obviously never presented a paper before
> your peers or else your skin would be thickened to the point that such
You obviously don't know how to use a citation index or bibliographic
reference, otherwise in the time it took you to post this, you would
have realized that I have, several times.
Also, you have a very poor opinion of scientific conferences, if you really
think that it's a bunch of name calling and petty insults.
> minor jabs would bounce right off. You're simply a government bureaucrat
Ah, the journalist can at least read - he sees I have a .gov address,
and thinks that means I work for the government. Of course, he's wrong,
I work for a corporation. And bureaucrats get paid more.
> masquerading as a scientist while sucking at the Uncle's hind tit who
He sure can take a wrong assumption and run miles with it in terms of
primitive insults.
> screamed his head off when poked. Now we know.
I doubt any net.person would describe my mild protest to your manic
diatribe as "screaming".
> John De Armond, WD4OQC |Interested in high performance mobility?
> Performance Engineering Magazine (TM) |
> Marietta, Ga |Interested in high tech and computers?
> j...@dixie.com |Write me about PE Magazine
> Need Usenet public Access in Atlanta? Write Me for info on Dixie.com.
See, I can read a sig too. From yours, you are either a journalist,
or a pitchman for the magazine. Not much to speak of in terms of
justifying yourself as a scientist. I'll give you the benefit of
the doubt and label you a journalist.
T.T. Cockerill
----------------------------------------
|*
|
Orifice Valve
|
|*
----------------------------------------
where the *'s represent tangential air inlets.
Air is blown in at near sonic velocity through the inlets to produce a stongly swirling flow. An air flow substantially cooler than the inlet exits through the orifice, while a warmer flow exits at the valve end. The valve controls the realative amounts of each, and hence, through an enthalpy balance, the temperature. Temperatures of -20 deg centigrade and +40 are quite possible, and I've seen reports (with a suitable high pressure air supply) of +150 and -50.
It must be said that the efficiency is pretty appauling, so its certainly not a realistic heat source, but it has found some application in specialised refrigeration tasks (particularly where there is a convenient air supply). We have an example in Cambridge that can produce 300W of cooling/heating power and it's a pretty poor design.
How does it work. Well that's a good question (in fact its my Phd). It looks likely that acoustic waves play some part, as does the decay of the swirl along the tube by frictional means. If you want some info email me and I'll send you something.
---------------------------------------
Tim Cockerill
Engineering Department,
University of Cambridge,
Cambridge,
U.K.
Jym Dyer
> they are much less effective at this than CFC's. Their ozone
> depletion potentials range from about .01 to .1 (compared to
> 1.0 for CFC-11).
=-= This comparison is certainly true, but you neglect to
address the magnitude of the damage being done. HCFCs are
just CFCs with hydrogen added to make them less stable, so
that they break up sooner.
=-= Given that CFCs yield 100 years of ozone depletion,
"sooner" means (to use your statistics) "only" 1-10 years.
This is better news, but it is by no means good news,
especially for those who'll be spending time in the near
future. :-|
> HCFC's are not an ideal solution (and I have never heard them
> advertised as such) . . .
=-= I've seen phrases like "CFC-free" and "ozone-friendly" used
for products that have replaced CFCs with HCFCs.
> . . . but I see no problem with using them in situations
> where better substitutes are not yet available.
=-= Again, the magnitude of the damage is such that I would have
to disagree.
> To determine whether a substitute is "better" one needs to
> consider a wide range of factors, including economic ones.
=-= On this I agree, but with one huge qualification: Most
systems for calculating "economic factors" aren't designed
for the real world, but for one in which resources are never
depleted and the costs of environmental damage is never even
considered. "Economic factors" that overlook such things
aren't worth the paper they're printed on.
<_Jym_>
Carl J Lydick
Odd. For once Jym posts something that vaguely touches on science, and then
directs followups to talk.environment. Odd. Followups redirected to
sci.energy and sci.environment.
=> While it is true that HCFC's contribute to ozone depletion,
=> they are much less effective at this than CFC's. Their ozone
=> depletion potentials range from about .01 to .1 (compared to
=> 1.0 for CFC-11).
=
==-= This comparison is certainly true, but you neglect to
=address the magnitude of the damage being done. HCFCs are
=just CFCs with hydrogen added to make them less stable, so
=that they break up sooner.
=
==-= Given that CFCs yield 100 years of ozone depletion,
="sooner" means (to use your statistics) "only" 1-10 years.
=This is better news, but it is by no means good news,
=especially for those who'll be spending time in the near
=future. :-|
Given that your description is accurate, then your conclusion is wrong. If the
HCFCs get to the stratosphere as easily as do the CFCs and break down more
easily once they're there, then there wouldn't be any significant difference in
their effects on the ozone. On the other hand, if the HCFCs are stable enough
to break down easily in the troposphere, then the total lag in effects on the
ozone will be the same, but the amount of catalyst involved will be cut by a
factor of 10.
The relative ease with which CFCs and HCFCs can break down would affect the
degree of ozone depletion, not the time scale on which the effects will be
seen.