From Wikipedia, the free encyclopedia
This article is about refrigerants.
The
Cool War is also a novel by
Frederik Pohl.
The Cool War refers to the debate about the
next-generation refrigerant in car air conditioning worldwide, with an
ongoing dispute between the Alliance for CO2
Solutions supporting the uptake of sustainable carbon dioxide
(CO2)as a refrigerant in passenger cars, and chemical
giants developing new chemical blends.[1]
The Alliance and its supporters – scientists, NGOs and business leaders
– urge the car industry to replace high global warming chemical
substances with the natural refrigerant carbon dioxide (CO2, R744 /
R-744) in car cooling and heating. This, they argue, would lead to
10% less car emissions, and knock out 1% of total greenhouse gas
emissions worldwide.[2] If
CO2 Technology is applied in other sectors, such as
commercial and industrial refrigeration, heat pumps for water
heating etc., it may even save up to 3% of the world’s greenhouse
gases.
Opponents of the Alliance claim that CO2 Technology
is not cost-efficient and safe, hence seeking to postpone the
global industry decision to be taken this summer to develop new
chemical blends instead.
Background
The Cool War has emanated from the decision of the European
Union to phase out the current high global warming refrigerant HFC-134a
in car air conditioning from January 2011 onwards.[3] To
comply with the legislation, carmakers have to decide today on a
new refrigerant, as they typically need 3-4 years to develop and
introduce a new car platform including the air conditioning system.
(It would take much less time to design merely a new air
conditioning system to install in a new version of an existing
model.) The current total value of the car air conditioning market
is estimated to be $14.5 billion in 2007.
Arguments for
CO2
The Alliance for CO2 Solutions and its supporters
agree that the refrigerant CO2 is:
- More environmentally friendly: with the lowest
Global warming potential (GWP)
of all currently used and proposed refrigerants. CO2
does not deplete the ozone layer. Since the carbon dioxide used in
car air conditioning is a recycled industrial waste product it
becomes environmentally neutral. Overall, using a
CO2-based air conditioning system will reduce total car
emissions by 10%, thereby sparing the planet 1% of total greenhouse
gases.
- More technically ready: CO2 models
have been developed and tested in all climates, being now ready for
mass production. They are faster to heat and cool a car, and show a
superior performance in over 90% of all driving conditions.
- More cost-efficient: As a refrigerant itself,
CO2 is cheap and worldwide available. The servicing of
CO2 systems will be less costly and less complicated
than that for present systems. For the consumer the total cost of
ownership is lowest with CO2 as it will significantly
cut fuel consumption by the air conditioning device. Carmakers have
to make an initial investment estimated at €20 per unit, with no
additional costs once CO2 Technology enters into mass
production.
- Use as Heat Pumps: At least one CO2
system under development can act as a heat pump, supplying cabin heat and
windshield defrosting even before the engine has warmed up. [4]
Arguments
against CO2
Opponents in The Cool War claim that CO2 Technology
is more expensive than current systems and future chemical blends
as it requires the design of completely new high-pressure systems
where so-called “drop-in solutions” (the adaptation of current
systems to new substances) would be more cost-efficient. Their
second key argument is that CO2 is toxic, leading to
suffocation in high concentrations.
Both arguments are challenged, however, by the Alliance for
CO2 Solutions. According to the group the initial costs
of CO2 systems will be around €5 higher than drop-in
solutions. Over a car’s life cycle, however, CO2 air
conditioning systems will be more cost-efficient than any currently
used or proposed new chemical blends. (see Arguments for CO2).
Regarding the issue of toxicity, CO2 has been classified
as Safety Class A1 (low-toxic, non-flammable refrigerant) by the
American Society of Heating, Refrigerating and Air-Conditioning
Engineers (ASHRAE) [5] – the
highest safety class possible. As the charge of CO2 to
the air conditioning systems is very small (200-400 g) there is no
realistic danger for the passengers, even in case of accidental
release.
Arguments for
non-CO2 refrigerants
- Natural: Refrigerants such as the
greenpeace-developed 'Greenfreeze', based on purified
butane/propane mixtures, are entirely 'natural', and due to
increased efficiency over refrigerants such as R134a, allow the use of very
small amounts of refrigerant to be used.
- Reduced environmental damage: Use of pure
hydrocarbon refrigerants, which are 'backward compatible' with even
early Freon
(R-12) car air conditioning systems, would allow these systems to
be easily converted (without modification), increasing their
efficiency, and preventing further release of harmful R-134a and
R-12 to the atmosphere.
Arguments against
non-CO2 refrigerants
Butane and propane are very flammable petroleum products; they
are used as fuels for gas barbecue grills, disposable lighters, etc.
Like gasoline, to which it chemically is closely related, propane
has a tendency to explode if ignited in an enclosed container.
The use of highly flammable hydrocarbon gases such as butane and
propane as automotive refrigerants raises serious safety concerns.
The EPA, in evaluating motor vehicle air conditioning substitutes
for CFC-12 (Freon, or R-12) under its SNAP program, has classified
as "Unacceptable Substitutes" other "Flammable blend[s] of
hydrocarbons" by reason of "insufficient data to demonstrate
safety." The EPA defines "Unacceptable" in this context as "illegal
for use as a CFC-12 substitute in motor vehicle air conditioners".
All of the refrigerants which EPA approved for motor vehicle use in
place of CFC-12 (as of September 28, 2006) contain no more than 4%
total flammable hydrocarbons (butane, isobutane, and/or
isopentane).[6]
Therefore, it appears unlikely, for safety reasons, that EPA will
approve 'Greenfreeze' or similar hydrocarbon-based refrigerants for
automotive use.
Latest and
next steps
In September 2007, the German Association of the Automotive
Industry (VDA) officially announced its decision to use
CO2 as the refrigerant in next-generation air
conditioning. Other carmakers from Europe and the rest of the world
may follow the German lead.
A working group at ACEA, the European carmakers’ association,
was to be drafting a common position on the issue to be adopted
across the whole industry by end-2007.
However on April 9th 2009, German public television channel ARD
aired a report claiming that VDA members would be using loopholes
in the law to avoid complying with the EU directive.[7]
Positions
Media
coverage
See also
- EcoCute, an energy
efficient electric heat pump that uses carbon dioxide as a
refrigerant
References
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