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From: (Bruce Hamilton)
Subject: Re: nonenergy economic growth becomes physically impossible
Date: Mon, 05 Oct 1998 10:36:56 GMT

Joshua Halpern <jbh@IDT.NET> wrote:

>In sci.environment Bruce Hamilton <> wrote:
>> (Scott Nudds) wrote:
[ On Greenfreeze ]
>> What about it?. You realise that it used fossil fuel materials, the
>> refrigerant was propane/butane and the foam was blown by cyclopentane,
>> which is, of course, a VOC - thus any US factories would have to install
>> expensive scrubbing equipment. Greenfreeze was produced by an existing
>> East German appliance manufacturer ( Foron ), who initially used
>> expanded polystyrene insulation and propane/isobutane refrigerant.
>Thanks for the interesting post.  I believe this point is slightly
>wrong.  As far as I can recall (I was in Germany about that time),
>the original design was done in the West after reunification
>and then manufactured somewhere in the new Federal states (Neue
>Bundeslande).   At the time it was stated that the licensing of the
>design to a company in the former East Germany, was an act of
>solidarity.  It may simply have been an inability to find a
>manufacturer in the original BRD that was interested in producing
>such a refrigerator, or an additional inducement to the likely
>purchasers of such a device.

I checked the article, and my comments reflected the content, so
I checked the WWW, and found the following at the Greenpeace site

There is a huge amount of anti-chemical industry drivel and,
unsurprisingly, an amazing amount of pro-environmentalist hype.
Nowhere, during my brief visit, could I find any mention of the
fact that CFC-blown insulation is superior to similar
cyclopentane-blown insulation - meaning that wall thicknesses have
to increase significantly for the same insulation. They also
conveniently forget to mention that all the HCs are derived from
fossil fuels, and that the cyclopentane-blowing would release
cyclopentane, a VOC ( with an occupational Threshold Limit Value
of 600ppm ) that would have to be scrubbed out from factory emissions
in the USA.

The writer conveniently blames the US chemical industry for the
absence of HCs in the US market, despite the fact that the article
I cited noted that GP, or a manufacturer of HC-filled systems, could
submit their systems to EPA for approval under SNAP, but none had.

The following extract also implies that Multilateral Fund subsidies
are available to countries that choose HC systems. Interestingly
the site lists a wide range of "Greenfreeze" models, but most didn't
appear to be frost-free, used around 400kWh for 200-300l capacity,
and had maximum cooling capacities of 4-12 kg / 24 hours. That's
still quite a lot of energy for such small units. The article I
cited listed the actual and projected annual energy use of US
refrigerators, which is decreasing - even though size and features
are increasing ( in kWh/year), partly because of NACE/DOE
engery-efficiency standards that became effective in 1990, 1993, and
1998. The 450 litre Sunfrost in the USA uses 250 kWh/year -
admittedly an expensive model, but the trend is still sharply

Year           Annual Energy Consumption
1970           1700 Actual
1975           1550
1980           1150
1985           1000
1990            950
1992            800
1995            550 Projected
1998            400
2000            380
2005            300
2010            250

Anyway, readers can make up their own minds, the article
I previously cited discusses many of the reasons why US
manufacturers are wary of HC refrigerants and HC-blown
insulation ( estimated at requiring 2-4% more energy by
HC proponents, and 10-12% by US opponents ). There are
valid points on both sides, But I would say that the USA
probably produces the most environmentally-friendly, and
user-friendly, refrigerators - as factory emissions are
also closely controlled, and the systems are much more
efficient than their bulk and style would imply.

[Begin extract ]

Greenfreeze hydrocarbon technology in domestic refrigeration is
environmentally the most sustainable technology that is currently
available in the world. It is cost effective, technologically mature,
and commercially accepted. The primary objective of the Greenpeace
Greenfreeze Project is the protection of the ozone layer and the
global climate through: (a) the worldwide propagation of the
Greenfreeze technology; and (b) the earliest possible retirement
of competing refrigeration technologies which use ozone depleting
and/or global warming substances, such as HCFCs or HFCs.


In the spring of 1992 Greenpeace brought together scientists who had
extensively researched the use of propane and butane as refrigerants,
with an East German company DKK Scharfenstein.

The meeting between the scientists and DKK Scharfenstein resulted in
the birth of 'Greenfreeze' technology for domestic refrigeration.

Greenfreeze uses a mixture of propane (R290) and isobutane (R60Oa), or
isobutane as a pure gas for the refrigerant. The energy efficiency of
the propane/butane refrigerators has proved to be as good as, or better
than those cooled with CFCs or HFC-134a.

Hydrocarbons are flammable but their flammability can be easily mitigated
through adequate safety measures in production and product design. The
content of propane or butane in a domestic 'Greenfreeze' refrigerator
equals roughly the content of two cigarette lighters.

When DKK Scharfenstein (renamed Foron) announced their intention to mass
produce "Greenfreeze", Greenpeace gathered tens of thousands of pre-orders
for the yet-to-be-produced new refrigerator from environmentally conscious
consumers in Germany. This overwhelming support from the public secured
the capital investment needed for the new 'Greenfreeze' product.

The major European household appliance manufacturers, who had already
invested in HFC-134a refrigeration technology as the substitute for
CFCs, were at first resistant to the hydrocarbon technology. However,
once DKK Scharfenstein proceeded with its plans, the major manufacturers
also began to convert to hydrocarbons. Within two years Greenfreeze has
become the dominant technology in Europe.


There are approximately 10 million Greenfreeze based refrigerators
in the world today. With an annual global refrigerator production of
65 million, Greenfreeze is less than 10% of the production volume.
It is nevertheless expanding. It is evident that Greenfreeze is by
far a preferable product, especially for developing countries. HFC
based refrigerators face large problems in servicing, as HFC 134-a
needs synthetic ester oil as lubricant, and this oil is very sensitive
to contamination by water vapour and other impurities.

Worldwide, of all the conversion projects approved under the Multilateral
Fund up to June 1996, out of a total of 8,070,800 refrigerator units,
5,884,400 will have hydrocarbon (cyclopentane) as blowing agent for the
insulation, and 2,186, 400 will be using HCFC 141-b.

Projected share of the market for hydrocarbon refrigerants in Western
/ Northern Europe is 80% by 1997, up from 40% in 1995. HFC 134-a is
expected to have 20% of the market in 1997, down from 50% in 1995.

Besides Europe, interest in Greenfreeze has been expressed in Argentina,
Cuba, China, Taiwan, and India. Some Japanese companies have converted
to hydrocarbons for insulation foam blowing, but none have yet selected
hydrocarbons for the refrigerant.

There is no Greenfreeze in North America (US and Canada) yet, although
consumers are beginning to ask for it. All the North American
manufacturers have switched from CFCs to HCFC and HFCs.

[ end extract ]

          Bruce Hamilton

From: (Bruce Hamilton)
Subject: Re: nonenergy economic growth becomes physically impossible
Date: 03 Oct 1998
Newsgroups: sci.econ,sci.environment,,,sci.physics (Scott Nudds) wrote:
>John McCarthy (jmc@Steam.Stanford.EDU) wrote:
>: Twenty years ago, or thereabouts, I asked the marketing director
>: for Gibson refrigerators, who happened to be sitting next to me
>: on an airplane, about the complaints that newer refrigerators had
>: insulation that would dry out and become non functional in ten
>: years.  He admitted it and claimed that people ought to replace
>: their refrigerators every ten years.  I was unconvinced.  I think
>: the problem doesn't exist any more, because I didn't see a
>: complaint when I last looked at refrigerator articles in Consumer
>: Reports.

Actually, the problem with the insulation was more to do with
the use of closed-cell rigid polyurethane foams to replace
the fibreglass insulation batts used previously. The original
fibreglass was completely open-cell, hence any condensation
on cold surfaces ( poor insulation ) would evaporate before
the next cycle.

The closed-cell foam was perceived as likely to trap the water
between it and the inner or outer surfaces. The cycling of the
fridge would generate freeze-thaw cycles would gradually
disrupt the rigid foam until a large block of ice ( an excellent
thermal conductor compared to closed-cell polyurethane foam )
would compromise the fridge.  In reality, the potential problem
was solved by carefully designing the vent holes ( needed when
the foam is produced in the cabinet ) and pipe orifices so that
they could be hermetically-sealed with plastic caps and/or special
caulking compound during final assembly.

Rigid, closed-cell polyurethane foams have much higher thermal
insulation values, consequently much thinner walls are needed,
yielding more internal capicity for the same kitchen space.
The mechanical and electrical systems for the original refrigerators
( not frost-free ) were designed for 25 years, and some newer
systems still have that design life, however others ( usually
lower-priced ) are designed for around 15-20 years.

>  Sounds good on the surface, but reality is quite different.  All
>refrigerators that I know of that are in common use still have their heat
>exchangers at the back <above> the primary heat source - the compressor.

Having the condenser ( one heat exchanger ) on the back is convenient,
but some models - particularly chest freezers - can use the whole cabinet.

The condenser location and design also induces air circulation
around the compressor, and the heat from the compressor is used to
evaporate any water that runs out from the refrigerator cabinet drains.
That humidity has to be removed to reduce corrosion, mould, mildew etc.
The other heat exchangers ( evaporators ) are inside the cabinet.

It's worth noting that most refrigerators have several heaters inside
the cabinet, usually around the magnetic door sealing strip. Otherwise
ice or condensation could build up, making opening the door very

>They also have their heat exchanger oriented in a manner that causes
>warmer air from below to rise over the higher portions of the exchanger.

Very few refrigerators have, or need, the sophistication of forced air
circulation around the condenser - it's usually only necessary when
the available space constrains the size of the surface.

>  The heat exchanger is also located <inside> the house, when
>significantly greater efficiency can be had by placing the exchanger
>outside in some shade.

Really?. If the outside ambient air temperature is higher than the
internal ( summer ) house temperature, then the effeciency
will be lower - unless you live in some strange universe where
our thermdynamic laws don't hold - quite possible, given the
usual hateful drivel you post, and the inclusion of
in the Newsgroups line.

However, the inherent complexity of split-system design ( they still
have to evaporate the drain water, remove compressor heat, and
prevent condensation on lines and the compressor ), really only
makes such designs economic for larger installations or locations
where the heat and/or humidity loads would be detrimental to
occupants or building services ( requiring larger air conditioners
to cope ).

Split systems also have problems - they require more refrigerant
charge ( larger internal volume ), aren't easily portable ( people
do relocate and also redesign their kitchens etc. ), use more
materials, are more prone to corrosion/weather etc. etc.

>  This last point is particularly interesting in that it illustrates how
>the market system is poor at considering solutions that are require
>experience across specialties - in this case home construction and
>refrigerator design.

No. Home refrigerators are excellent examples of interdisciplinary

Refrigerator models are designed by mechanical, electrical, and
  control engineers to match the requirements of particular market
  niches, with regard to capacity, price, and durability.
The factories to produce the refrigerators are designed and built
  by process, electrical, and mechanical engineers and construction
  companies, and are always being upgraded to improve efficiency
  and lower the production costs and environmental emissions.
The refrigeration systems are designed by specialist refrigeration
  engineers to match the specification, and they include such
  goodies as high capacity zeolite driers in place of the old silica
  gel driers, capillary tubing in place of expansion valves, and
  hermetic systems ( motor, compressor, lubricant inside one housing )
  in place of the old external drive systems.
Refrigerants are developed by sythetic chemists to meet specific
  market requirements - in 1930s, CFCs to be less toxic/flammable, in
  the 1980s to be less environmentally-harmful and even more-efficient
Insulation is developed by polymer chemists to be durable and
  efficient. Since then engineers, metallurigists, and physicists
  have developed vacuum panel insulataion, aerogel insulation etc..
Sealants, coatings, and corrosion-resistant finishes have been
  developed by industrial chemists and rheology experts.
Plastic liners have been developed by polymer chemists to replace
  the durable, but expensive viteous enamel liners.
Alumimium-alloy clad aluminium ( yes, two alloys fused together )
  has been developed that can be formed into the evaporators.
Bundy-tubing ( cheaper steel sheet ( with a flash coating of copper )
  that is wrapped 720 degrees and heat fused to form a more rigid,
  much cheaper tube than copper.
Precoated, thinner, stronger, steel has been produced to make cabinets
  cheaper and more scratch-resistant than early models that required
  huge, inefficient, sprayed paint and oven baking of formed cabinets.
Control systems have been designed by engineers to optimise both system
  capacity ( sized according to the peak load - when an empty cabinet
  is filled with warm food, there must be sufficent capacity to reduce
  food temperature before the food can spoil ) and energy use to maintain
etc. etc.

In other words current domestic refrigerators are produced, installed,
and maintained, by diverse, highly-skilled, tradespeople and professionals.
They represent excellent and efficient utilisation of technology in the
servive of humanity - omething that can't be said of your Usenet posts.

>  What about Greenfreeze Mr. McCarthy?

What about it?. You realise that it used fossil fuel materials, the
refrigerant was propane/butane and the foam was blown by cyclopentane,
which is, of course, a VOC - thus any US factories would have to install
expensive scrubbing equipment. Greenfreeze was produced by an existing
East German appliance manufacturer ( Foron ), who initially used
expanded polystyrene insulation and propane/isobutane refrigerant.

  " The company was on the verge of going out of business, and other
    European manufacturers were leaning strongly toward HFC and HCFC
    replacements for CFCs, when Greenpeace started a grass roots
    campaign by asking people to place orders for an environmnetally
    friendly refrigerator. According to Rosas [ Greenpeace's Ozone
    campaigner ], that campaign yielded 70,000 direct orders"

'Green Refrigerators' T.S.Perry  IEEE Spectrum August 1994 p.25-30.
The expanded polystyrene was replaced with cyclopentane-blown foam.
Thus the Greenfreeze was a product of industry skills, not Greenpeace.
Greenfreeze was a niche created by marketing to people who were
prepared to pay an upfront premium to be green, and not a product that
was made using green methods. There is no evidence that the overall
"green balance" of the Greenfreeze was any better for the planet
( being produced initially in the former East Germany :-) ) than
conventional refrigerators, even though it might have been more
ozone-layer friendly.

There have been concerns that the production facilities for the
Greenfreeze would be expensive to modify for compliance to US EPA
and OSHA criteria, and thus the Greenfreeze price would be much
higher from US facilities. Also, major manufacturers are concerned
that they could end up in litigation because of the added flammability
risks during production, distribution, storage and in end-use homes.

The above article has plenty of detail about proposed new components
and systems, including Whirlpool's " Super Efficient Refrigerator "
and acoustic refrigerators.

Followups set to only. Unfortunately for today's Usenet,
posters like Hanson and Nudds seem to believe the louder they shout
their drivel, the more likely that they'll find the one-a-minute

        Bruce Hamilton

From: (Bruce Hamilton)
Subject: Re: nonenergy economic growth becomes physically impossible
Date: 03 Oct 1998
Newsgroups: sci.econ,sci.environment,,,sci.physics

Joshua Halpern <jbh@IDT.NET> wrote:

>Very old refrigerators had their compressors on top of the unit.
>Does anyone know why this was changed?  (Serious question)

I could look it up to check, but my guess would be because the
introduction of hermetic systems, where the compressor and motor
were also sealed into the system. That mean that instead of just
refrigerant ( Freon ) the compressor was pumping a mix of
lubricant ( thin mineral oil for Freons ) and refrigerant. The
hot, compressed oil/gas mixture is condensed in the condenser
and the oil slowly runs down ( under gravity ) back to the
compressor reservoir, where it is reused ( splash lubrication ).

If you put the compressor at the top, you would have to resize
the lines to prevent plugging and slugs of oil - which would
lower the efficiency, and could cause hydraulic lock ( motor
burnout due to stalling ), as well as arrange some sort of
positive lubrication system. What appears to be a
thermodynamically-simple device is actually a complex domestic
appliance that has been refined over the decades to match the
refrigeration needs of households for the price they are
prepared to pay. That doesn't means alternatives won't succeed,
just that they either have to be better in the eyes of the
customer or they have to have external forces ( subsidies ) to
help them.

Don't worry - improvement is surely trivial, after all, Nudds
is smarter than all the industry - he knows that new models are
solely marketing devices, whereas most would understand that
each new iteration usually improves the product ( less volume
of refrigerants, lower energy consumption, better control, lower
cost, new materials, etc. etc. ).

Products that don't improve with each new iteration are Nudds'
and Hanson's posts. Followups set to

           Bruce Hamilton

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