[Ian Williams]

HFC`s which are used in our so called eco-friendly refridgerators which replaced CFC`s and HCFC`s in the late 80`s as a greener safer option now it looks like it may hamper mankind in halting Climate change and Ozone depletion!

A rise in the use of "ozone-friendly" HFCs has prompted experts to voice concerns that the potent greenhouse gases could be a problem in the future.

A UN report says that HFCs, many more times potent than CO2, could account for up to 20% of emissions and hamper efforts to curb climate change.

They are widely used in fridges and air conditioning, replacing CFCs and HCFCs that damage the Earth's ozone layer.

The findings were presented during a meeting on protecting the ozone layer.




Full story http://www.bbc.co.uk...onment-15818659

This post has been edited by Ian Williams: 21 November 2011 - 18:49

[Ian Williams]

Full report (PDF File)

http://www.unep.org/.../HFC_report.pdf

[ldavidcooke]

Ian Williams, on 21 November 2011 - 16:07, said:

Full report (PDF File)

http://www.unep.org/.../HFC_report.pdf

Hey Ian,

I am concerned that the concern elicited could be a bit misleading, HFCs in an atmospheric release have a very short life. Generally, the hydrogen will quickly detach, the florine being somewhat more attracted to the sodium in the atmospheric aerosols would likely raidly drop the association with the carbon. At less then a mt of generation, much less release annually, most by products would precipitate out before reaching above the marine layer as to the release of a chlorine ion, yep it will occur at about the same rate as a UV particle would disassociate a SodiumChloride molecule. Though with much fewer Floride atoms and a stronger sodium bond, most of the chlorine will precipitate out in rain before crossing over into the Stratosphere. Hmmm..., seems I have heard this argument before..., Okay, you have my attention.

So what is the alternative?

[Ian Williams]

Hi Dave, The alternatives all look expensive to me, from the report

There are options available to minimize the climate
influence of HFCs
Alternative technical options for minimizing the influence
of HFCs on climate fall into three categories:
• Alternative methods and processes (also called ‘notin-
kind’ alternatives): Commercially used examples
include fibre insulation materials, dry-powder asthma
inhalers and building designs that avoid the need for
air-conditioners.
• Using non-HFC substances with low or zero GWP:
Commercially used examples include hydrocarbons,
ammonia, CO2, dimethyl ether and other diverse
substances used in various types of foam products,
refrigeration, and fire protection systems.

• Using low-GWP HFCs: HFCs currently in use have a
range of atmospheric lifetimes and GWPs (the shorter
the lifetime, the lower the GWP). The mix of HFCs
in current use, weighted by usage (tonnage), has an
average lifetime of 15 years. However, several low-
GWP HFCs (with lifetimes of less than a few months)
are now being introduced, e.g. HFC-1234ze in foam
products and HFC-1234yf for mobile air-conditioners.

As a general conclusion about HFC alternatives, it can
be said that there is no ‘one-size-fits-all’ solution. The
solution that works best will depend on many factors such
as the local situation for production and use, the costs of
different alternatives, the availability of components, and
the feasibility of implementation.

[ldavidcooke]

Hey Ian,

Actually, I had not intended to be as specific as much as general; however, that may not have been in keeping with your intent...

I was thinking more along the lines of containment, such as a sodium chloride bath of the expansion/cooling coils. (The problem being dealing with the corrosive issue, though that the sodium solar power towers seemed to have resolved this issue it should not prove to be terribly expensive...)

Actually, I was thinking on the order of ammonia cooling, though they prove to be both hazardous and corrosive. Of course for suburban installations geothermal is a possibility, whether buried coils or drilled wells. Alternatively there is the possibility to use thermoelectric systems, easily reversable and if large enough more then sufficient to offer a 30 degree differential. (Though at 12% efficient not as good as a vapor expansion/compression heat exchanger.)

It really comes down to IF we are going to either adapt or isolate ourselves from nature. That in the last century we have moved from little more then wooden shacks with many a homespun cover to keep us warm as we cook over a wood/coal fed fire. It is almost we have distanced ourselves too much...

Of course, you have to keep indoor plumbing warm enough to flow and provide a means to wash and dry our clothes and keep our food fresh. In essence, it would seem we have gone overboard to some degree in the attempt to control our environment.

So, let me try to reword my question, given the issues with man made solutions for environmental controls, what would you see as reasonable alternatives?

[Ian Williams]

HI Dave, I think you have me all wrong, Probably my fault with the title of the thread so have changed the exclamation mark with a question mark.

The whole AGW thing for me came about or at least to my attention in the late 80`s with the abandonment of CFC gases etc, so they replace it with a much safer HFC gas, only for us to now learn that, that may now not be safe, moving the goalposts? In the report they say there are now HFC`s which erode within months instead of say 15 years so maybe thats the answer, but after 20 odd years with HFC`s in our fridges, air cons etc here we are again possibly back to square one! Why are they not using this lower HFC in all new products now?

Just heard on the BBC a few mins ago the world has increased its CO2 by 2.3 ppm between 2009 and 2010 which exceeds the decadal average of 2.0 ppm and one scientist on there jumped on and said that we are now looking at the higher end of how much we warm by the end of the century. I remain unconvinced!

[ldavidcooke]

Ian Williams, on 21 November 2011 - 19:06, said:

HI Dave, I think you have me all wrong, Probably my fault with the title of the thread so have changed the exclamation mark with a question mark.

The whole AGW thing for me came about or at least to my attention in the late 80`s with the abandonment of CFC gases etc, so they replace it with a much safer HFC gas, only for us to now learn that, that may now not be safe, moving the goalposts? In the report they say there are now HFC`s which erode within months instead of say 15 years so maybe thats the answer, but after 20 odd years with HFC`s in our fridges, air cons etc here we are again possibly back to square one! Why are they not using this lower HFC in all new products now?

Just heard on the BBC a few mins ago the world has increased its CO2 by 2.3 ppm between 2009 and 2010 which exceeds the decadal average of 2.0 ppm and one scientist on there jumped on and said that we are now looking at the higher end of how much we warm by the end of the century. I remain unconvinced!

Hey Ian,

As are many, unconvinced... I believe that natural variation will likely set up to balance off some of the warming potential. However, once we lose the majority of year round polar ice cover it is probable the many will be in for a shock.

Not that the highs will be worse; but, that the lows will not be as low. Heat flow should increase and temperate seasons expand. Subtropical storms should increase and seasonal weather ridges/trouths in the temperate through the polar zones become more dominate.

That the expansion of emissions is dropping here in the States there is less of an ability to affect the annual loading of the atmosphere. Within 10 yrs it may be possible we too could be watching the developing countries further endanger the rest of us. Unless we can put our errors back in the ground, (IE: Bury our carbon heavy wastes.), it is likely the arguement that they have an equivalent right. (In truth, where we had 1/2 million over 50 years, the 2 billion will exhaust their argument in 12.5 years starting around 2006. This means by 2020, we will have parity and need to be working to put the "genie back in the bottle".

Demand here for fossil fuels are beginning to wane in the better economic circles. It is the other 90% that will have to wait the 10 years for low carbon technology to trickle down to them... It is likely another 20 years to reach the 3rd world.

Ozone, HFCs and their cousins are not the make or break threats some want to suggest. Warming or excessive UV in or of itself is not a threat if we sequest ourselves away in climate controlled environs. (Versus environmentaly controlled climates?) It has more to do with the rest of life on the planet. Do we really want to convert the planet to spaceship Earth...? (It would seem smarter to choose a more geostable planet...)

I think it may be a better idea to try to distribute the best we would want to move forward with by 2020 to higher latitudes or climate controlled enclosures, (My first question is which Great Lake are we going to tap. With the second question being who is building the air conditioned greenhouse for the Redwood/Sequoia forest? I want to invest now so that when mine get of age they can afford a berth...)