What is next generation Refrigerants?

[david2008]

Hey,
I am newer to RE. A very good forum. Consider refrigerant, what is the most popular in current time? R134a?


What is next generation Refrigerants? CO2?

(both for vapor compression cycle)

Thanks in advance.

David:D

[nh3wizard]

I don't know if I would consider CO2 as a "Next" generation refrigerant but maybe one coming back into the spotlight.:D

[PVA]

I think that only natural refrigerant (ammonia, CO2, water, propan, air and other) will be in future, but maybe some professor will invent new refrigerant, much better than this. :D

[NoNickName]

CO2 is gaining momentum. Availability of components is increasing.

[US Iceman]

I like ammonia and CO2. Propane is a good refrigerant, but for large systems there are some safety issues to be concerned with.

[750 Valve]

agreed, natural refrigerants will be the go in the future

[ice_cool]

R404a is most popularly used.

[Uni]

Some comments :),

Hydrocarbons (HCs) have been widely accepted as good refrigerants, well-behaved, well compatible, comparable in performance with the CFCs they are replacing. The major concerns that restrict the use of HCs are with their flammability and primarily with the insurance risks involved. Other issues are the safety concern in handling relatively large HC charge levels, special installation practices and field service skills. Although HCs are widely applied in Europe, there are restrictions elsewhere like in some states of Australia and America. If we can improve system design and optimise the charge amount in addition to less stringent regulations, HCs may dominate the market.

Hopefully Dupont and Honeywell would be successful with their new developing refrigerant. A lot of work has been done by the cooperation of Honywell and Dupont in studying the characteristics of their new proposed refrigerant, HFO-1234yf. The candidate has excellent environmental properties, low toxicity, very low GWP of 4, zero ODP, similar system performance to R134a, excellent COP and capacity and no glide although mildly flammable. The next steps are to complete property testing (vehicle cooling performance, compatibility and stability), toxicity testing (rabbit developmental, reproductive), multiple risk assessments (fault trees, computational fluid dynamics modeling, vehicle flammability testing) and obtain approvals (Spartz and Minor 2008).

Other candidates are as follows (Calm 2008):

‘‘Natural Refrigerants’’ (NH3, CO2, HCs, H2O, air)
Considerations: Efficiency, for NH3 and HCs also flammability

Low GWP HFCs (R-32, R-152a, R-161,.)
Considerations: Flammability; most suppressants have high GWP

HFEs
Considerations: Disappointing thus far, still?

HCs, HEs (R-290, R-600, R-E170,.)
Considerations: Flammability

HFICs, FICs (R-31I1 (CH2FI), R-13I1 (CF3I),.)
Considerations: Cost, ODP > 0 but not in MP, some are toxic; compatibility?

Fluorinated alcohols (–OH), fluorinated ketones (–(C==O)–)
Efficiency? Flammability? Toxicity? Compatibility?
References:

Spartz, M & Minor, B 2008, 'HFO-1234yf - A low GWP refrigerant for MAC', VDA Alternative Refirgerant Winter Meeting 2008, Saalfelden, Austria, 13-14 February 2008, Honeywell & Dupont.

Calm, JM 2008, 'The next generation of refrigerants - Historical review, considerations, and outlook', International Journal of Refrigeration, vol. 31, no. 7, pp. 1123-1133.

[NoNickName]

1234yf? Not quite. Have a look

http://www.r744.com/articles/2008-10-31-toyota-moves-away-from-1234yf-says-duh.php

http://www.youtube.com/watch?v=yf1NpY9qIY8

[Uni]

Thanks for more info, NoNickName

It's obvious that Honeywell and Dupont have not finished their tests and not received approval. As I mentioned, there are much more to do. However, have a look at their report prepared for the conference and we can see that they were doing it properly.

The info read from R744.com is useful for us somehow. However, I suggest the more reliable source of information should come from peer reviewed journals. One of the first lesson I learnt in uni was finding and judging info and source of info.

I will wait and see for more. We will have a closed look on their jobs - I mean both sides - CO2 supporters and 1234yf developers. In Europe, 2011 is coming so as the refrigerants war ;)

[keisersosei]

Natural will have to be the way to go soon in Australia, our guys in charge, probably Peter Garrett are starting on implementing taxes per tonne of global warming potential... from what i hear, is that there wil be an additional cost of $20.00 AU per tonne per kilo of refrigerant.. so R404A has a GWP of around 3500 (ish) so add around $60.00 AU (PER KILO!!!) onto the current price..
R134a on the other and has a GWP of 1300 (ish) so your lookig at ONLY another $20.00 per kilo

Imagine using R12 still.....around 10 000 GWP!!!

[BobTheBull]

To rehash something I ran across in another forum somewhere (I would credit but have not idea where or who): There has been an immense amount of R&D done on this subject, and the current mishmash of 400's and 500's is the result. Considering the effort and expense already spent it is unlikely to see anything more on this front.

Next gen? The Honeywell/DuPont project is the only thing I know of that is serious. And they are still working on it.

Uni summed up the alternatives very well; these are, of course, old gen for the most part, especially the most viable, CO2, HC's and ammonia. CO2 is the major bugaboo in global warming; HC's are also bugaboos, but only if they are combusted. As natural gases, however, I think they are fairly benign (excluding methane). Ammonia has well known problems and unlikely to be seen in other that large industrial applications.

Thus, it seems likely the true next gen refrigerant is not on the horizon yet, and will appear after some breakthrough discovery. Or, there is no next gen and will make it work with the plethora of known refrigerants available.