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Posted

"Roughly 5% of greenhouse gases come from sources that are entirely human made.

These include the hydroflurocarbons (HFCs) perfluorocarbons and sulphur hexafluride"

(Source Wiggins and Winn The Five Biggest Unsolved Problems in Science Wiley 2003)

Apparently these are used in a variety of industrial processes.

Why do we need them?

Why are they not banned?

Posted

my best bet is it would cost some people money to convert various things to something else. everything is money, so the only really effective way of doing something is providing a cost effective and relativly painless alternative. something most "green" methods cant offer at present. makes me sad.

Posted

Apparently these are used in a variety of industrial processes.

Why do we need them?

Why are they not banned?

 

 

hydroflurocarbons

 

These were touted as the replacement for CFC laden refrigerants. I remember when the change took place and people around me (who had upgraded old equipment such as refrigerators, air conditioners, etc) complained about the new stuff not being as good as the old stuff. Having to turn the products up higher to achieve the same level of comfort/coldness. They also commented about the lack of change in their utility bills, having expected seeing a reduction in these due to their purchace of the newest product (this was during the first years of the switchover).

 

Within the last few years, while reading another forum someone posted a relevant article with associated links regarding how this change had actually cost more in the burning of fossil fuels. I read most of the links provided and was shocked to see the numbers and how much it cost for this less efficent method of cooling. The projected costs increased the refrigerant costs by 10% by including several factors often ignored by others promoting the switchover, such as reduced life expentancy of the newer products. The numbers projected for increased energy consumption in africa was even higher, and this poster pointed out the increasing availabilty of refrigerants in Africa and other developing nations. It was suggested by this individual that rather than switching to a lesser of two evils (CFC vs HFC), the world community would have been better served by simply requiring a better method of recovery of refrigerants (such as was implemented with the mandated phase out of older methods of cooling). It was an interesting aspect of the CFC vs Ozone arguement that I had never seen portrayed before.

 

Quote from this link

Refrigeration Technology: Moving Towards Sustainability

 

"Over the last 15 years the refrigeration industry has undergone at least 7 technological or process changes every time step better, emission rates of even alternatives were reduced by 90 % , and the energy efficiency gains in chillers and in domestic refrigerator were between 35 and 45%."

 

The other part of this that is not mentioned relates to what I posted earlier about CFC type coolants being a better product. The advances in the machinery involved to drive this technology is the significant part of the energy savings rather than the switchover to the non-CFC base coolant.

 

I remember when we finally had to purchace a new fridge. The existing fridge that came with this house was an old type machine and its compressor motor finally burned out. I did notice a drop in my electric bill for the first year or so, but then it began to creep up. This newer machine is begining to fail and I have had to reset my temp controls several times over the last few years to keep my food cold. Its been years since I have been able to keep ice cream rock hard. The old machine was 25-30 years old when it failed and it was still cooling great (meaning the freon was working just fine). This newer machine is around 15 years old and I have been steadily disapointed in its effiency for the last 5 years. My mom purchaced a new fridge also around 7 years ago. She is seeing the same thing with hers loosing its cooling ability already. Its seems to me this newer cooling product breaks down/looses potency faster and thus causes increased work on the motors vs the older coolents. Myself, I am not sure we couldnt do a better job now by reinstating the old freon product with the better mechanical technologies combined with the stricter recovery methods now in place.

 

As far as car A/C you would need input from others with more experience. I dont have A/C in my cars and dont want it due to the pressure it puts on the motor and the loss of gas milage. But I do know I had a couple cans of the old car refrigerant on the shelf in the garage and the sticker price was around $2 a can. Someone spotted these on my shelves and gave me $15 a can cuz they hated the new stuff (doesnt work as good) and nobody can find the old stuff. So are we burning more gas to run less effective A/C in cars?

 

I am not convinced the lets ban everything now and worry about alternatives later approach is the long term solution. There is a cause/effect relationship that needs to be considered before laying down the law.

 

Perfluorocarbon

 

List of refrigerants

 

Sulfur hexafluoride

 

"SF6 is used by the electricity industry as a gaseous dielectric medium for high-voltage (1 kV and above) circuit breakers, switchgear, and other electrical equipment, often replacing harmful PCBs."

Posted

Well...in the hazy world of environmental science...often one doesnt know what to believe..and whats hidden underneath.

 

But...if u do accept that the detrimental effects of the CFCs on the Ozone layer were true...and as great as the scientists predicted them to be....then...doesnt this statement become absurd...

 

..."I am not convinced the lets ban everything now and worry about alternatives later approach is the long term solution. There is a cause/effect relationship that needs to be considered before laying down the law."

 

Do we really sit and study the cause/effect relationships....knowing well...that something that we are doing (emitting, CFCs i mean) is depleting the ozone layer at the poles and letting the harmful and carcinogenic UV rays to penetrate the atmoshphere and reach the ground level?

 

And isnt that what everyone is doing? Finding out the cause/effect of phasing out GHGs, the cause/effect of using environmentally sound technology!?

Posted
Well...in the hazy world of environmental science...often one doesnt know what to believe..and whats hidden underneath.

 

But...if u do accept that the detrimental effects of the CFCs on the Ozone layer were true...and as great as the scientists predicted them to be....then...doesnt this statement become absurd...

 

the hazy world of enviro science was exactly my point.

 

These same authorities on the effects of CFCs predicted a much longer recovery/dispersement of the CFCs (if I remember right 40-100 years before seeing reductions in the atmospheric levels). They were wrong.

 

..."I am not convinced the lets ban everything now and worry about alternatives later approach is the long term solution. There is a cause/effect relationship that needs to be considered before laying down the law."

 

Do we really sit and study the cause/effect relationships....knowing well...that something that we are doing (emitting, CFCs i mean) is depleting the ozone layer at the poles and letting the harmful and carcinogenic UV rays to penetrate the atmoshphere and reach the ground level?

 

And isnt that what everyone is doing? Finding out the cause/effect of phasing out GHGs, the cause/effect of using environmentally sound technology!?

 

I am not sure you fully understand what I was implying with my post. The actual problem with CFCs wasnt their use, it was their escaping into the atmosphere via bad practices in recycling and mechanical issues. As my link shows, the real changes in the refrigeration industries address these issues in a remarkable fashion but we are still using products that

 

1. impact greenhouse gasses at a remarkable rate and;

2. are less effective in producing the desired results (refrigeration/cooling) and;

3. this less effective method results in increased greenhouse gas production to compensate for the non-ozone damaging (but harmful in the big picture of greenhouse issues) via increased workload on the mechanics involved in creating cooling and;

4. The use of refrigeration/coolant is expected to rise greatly as places such as africa and india and china implement more of these products to larger and larger populations.

 

If the older methods of refrigeration/cooling resulted in the machinery itself lasting twice as long and with the advances in coolant recovery/mechanicals were applied with this much better source of coolant, would we as a whole be better off environmentally by using the better product now that we address the actual issue of escaping coolants with a much higher degree of recovery and effiency.

Posted

Well...its still best that we get rid of anythin that produced CFCs in the first place.

 

For no matter what regulation one puts...if its produced..ultimately...it will be released into the environment...and cause deleterious effects.

  • 3 weeks later...
Posted

I completely agree Cedars and I still don't think that Govind gets your point.

 

I think it happens in more greening initiatives than just CFC's too.

 

There is a tendancy to miss looking at the whole picture in regards to making something more "green".

 

Sure running a bus on Ethanol produces less emissions (from the bus) but by the time you get the ethanol in the bus in the first place you're not making a huge difference (making it worse?) to total emissions.

Posted
I completely agree Cedars and I still don't think that Govind gets your point.

 

I think it happens in more greening initiatives than just CFC's too.

 

There is a tendancy to miss looking at the whole picture in regards to making something more "green".

Yes "life was not meant to be easy" Easy solutions seem often to be wrong

 

Sure running a bus on Ethanol produces less emissions (from the bus) but by the time you get the ethanol in the bus in the first place you're not making a huge difference (making it worse?) to total emissions.

That may be the case in the Us where ethanol is made from corn. But in Australia we make it from sugar cane. I suspect that is more environmentally friendly.(?) At least the government thingks so; they are about to mandate future ethanol/petrol mixes.

  • 2 weeks later...
Posted

I believe that I have read that now HFC's are causing more danger than CFC's. But, personally I think that it is very difficult to ban these man-made greenhouse gases. If you think about it, many things like cars, power plants also produce greenhouse gases, how do you stop cars from travelling...

Posted
But...if u do accept that the detrimental effects of the CFCs on the Ozone layer were true...and as great as the scientists predicted them to be....then...doesnt this statement become absurd...

 

..."I am not convinced the lets ban everything now and worry about alternatives later approach is the long term solution. There is a cause/effect relationship that needs to be considered before laying down the law."

 

Do we really sit and study the cause/effect relationships....knowing well...that something that we are doing (emitting, CFCs i mean) is depleting the ozone layer at the poles and letting the harmful and carcinogenic UV rays to penetrate the atmoshphere and reach the ground level?

 

And what happens when the cure is worse than the disease?

Posted

You find another cure;)

 

As for the earlier post that asked if we were to stop using cars, I love this question.

 

Heavens NO. Just make cars that have engines that are more than 12%-15% efficient (on average), and use more efficiently generated fuel as well.

Posted
You find another cure;)

 

As for the earlier post that asked if we were to stop using cars, I love this question.

 

Heavens NO. Just make cars that have engines that are more than 12%-15% efficient (on average), and use more efficiently generated fuel as well.

 

And let me ask you how many people on this planet do that??? Do you know the carbon dioxide produced by cars aren't decreasing. And won't making it more efficient = more expensieve and how many car manufacturer actually tries to make it more efficient and environment friendly.

Posted
And let me ask you how many people on this planet do that???

 

I'm sorry, do what? Use more efficient vehicles if available? Certainly not everyone, but also certainly some people do.

 

Do you know the carbon dioxide produced by cars aren't decreasing.

 

I am painfully aware of that. While some more vehicles have become more efficient, many have not. In addition many more cars are on the road than there were a few years ago.

 

And won't making it more efficient = more expensieve and how many car manufacturer actually tries to make it more efficient and environment friendly.

 

Yes, advances have been made in engines. However, instead of putting these advances into efficiency, the manufacturers have put it into increased horsepower.

 

And yes, any new technology is going to be more expensive (as a general rule, I am sure there are exceptions). However, due to the nature of markets, I am certain there won't be a on-off switch for efficient vehicles. I.E. the inefficient old technology won't disappear one day when the new efficient cars appear. People that value the efficiency will buy one, people that don't, won't. We see that already which is one of the reasons Ford is in such deep trouble.

Posted

That may be the case in the Us where ethanol is made from corn. But in Australia we make it from sugar cane. I suspect that is more environmentally friendly.(?) At least the government thingks so; they are about to mandate future ethanol/petrol mixes.

 

Interesting. I dont know that its more enviromentally friendly, it does have its own issues. But my only (narrow) knowledge of the sugar cane industry is via the florida everglades and the impact there (negative). But searching today I found out that the region isnt very condusive to the growing of cane. Seems there are some issues being studied in Au about potential impact:

 

1. DIRECTOR’S REPORT

 

Here is a question I do have regarding this issue and AU. How much land are you willing to convert to sugar cane production?

 

Map of current cane production areas at bottom:

Australian Primary Industries - Sugar Cane

 

I dont know enough about australia to be able to calculate how much of this region would need to be converted to meet AUs needs for fuel. It does appear that any excess runoff would dump directly into the Reef area and would need to be addressed very strictly. Runoff is a very significant impact in the everglades and one of the negatives regarding cane growing in that region.

 

This wiki article does give a better idea of how much excess energy can be produced via cane:

 

Ethanol fuel in Brazil - Wikipedia, the free encyclopedia

 

It does seem the USA is on the wrong course via corn to ethanol. I wonder how much better sugar beets would be compared to corn.

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