AC cryogenic agent used?

AC cryogenic agent used?

Esteemed readers,

the stuff currently used in car AC is R134a, a hydrofluorocarbon (HFC). It's used in the Roadster, too. European union regulations decreed to avoid R134a in all new cars sold within EU, beginning with 2011. R134a is to be replaced with something "better for the climate" - R1234yf which is still a HFC. R744 (plain CO2) was in discussion but the car industry dropped it for cost reasons. Economics of scale make it reasonable to me that all ICE cars will go with R1234yf in the long term.

Please TESLA I want my Model S without CFC, HFC, or similar stuff inside the AC. Go for R744. Since all ICE assisted subsystems have to be redesigned in an EV, there is a real chance to make a switch to environment friendly AC at little additional cost, if any.

Volker.Berlin | April 1, 2011

You mean "cost prohibitive" as in "EVs are economically not feasible"? C'mon, as a Tesla owner or reservation holder, you should be able to look beyond this cheap (pun!) argument.

Brian H | April 1, 2011

The whole CFC thing was a hoax, or at best a hyped error. Ozone variations have nothing to do with human CFC emissions. So don't get all tangled with greenscam rhetoric.

Timo | April 1, 2011

@Brian H, you are obviously human effect to environment denialist. Not skeptic, denialist.

Humans have heavy effect on greenhouse gases, ozone layer, cloud coverage and several other factors by changing local environments here and there. Global warming is a fact, polar ice sheets are melting away, sea temperature is rising etc.. How much of it is human actions result is debatable, but effect most certainly is not zero.

There has been already major changes to climate. North-East Passage is already open, if same happens to North of Canada we get change in sea currents. That changes whole northern global climate very very drastically.

Also there has been change in rain patterns and much worse storms than before indicating that more heat and moisture from sea is getting into atmosphere. Storm routes are changing. The next time New Orleans get hit by hurricane it might be category 5 one, and from that it might not be so "easy" to recover. Sea might reclaim whole area permanently. New York might get in the way of such storm in near future. That would be bad for Manhattan area.

Life goes on, that is not the issue. It might actually like the change. Problem is us humans in changing environment. It hurts us.

Brian H | April 1, 2011

This is not the venue for the discussion, but drop over to and weigh in*. You might learn something about the supposed "evidence" for your claims.

*(Site was voted Best Science Blog for 2010, so it's the real deal.)

Sudre | April 1, 2011

I somewhat agree with Brain H on the ozone issue but not totally. It's like saying electricity should be illegal because it escapes the insulation on the wire and people might get killed by it. The trick is to keep the wire properly insulated.

The Ozone Layer is recovering. If you find evidence that it's not then Brian is totally correct and it's all just random madness.

Lets not multiply costs when it might not be needed. Adjustments have been made to curb the venting of ozone depleting products. It seems to be working.

On the whole global warming thing tho... I think Brian and his experts better start explaining why ice caps and Glaciers are melting if there is no warming..... Man made or not.

Brian H | April 1, 2011

Actually, the timing is all wrong. It was s'posed to take 30 yrs for the reduction to work, but natural fluctuations reduced it early. Nothing to do with the fluorocarbons.

Sudre | April 1, 2011

Read the article or at least scan it Brian. It's not fixed. I/they said it's recovering. It's not even at the 1980's level yet... where it was when first discovered as a problem.

Timo | April 1, 2011

What I stated were not "claims" they were measured facts. Only thing debatable is how big impact humans have in all of this.

Fact: CO2 is greenhouse gas. Fact: greenhouse effect prevents this ball from freezing over. Fact: we dump more and more CO2 into atmosphere. It would be just crazy to claim that it has no effect.

Greenhouse effect has tendency to balance out temperature differences, so biggest effect it has are in polar areas.

If there is natural heating happening at the same time, then we certainly should not try to make things worse.

Brian H | April 3, 2011

You mean better.

Warming historically resulted in boom times for humanity and the vast majority of other species, including warming far in excess of the most idiotic of the IPCC "projections". We're in a 60-yr cyclical pattern overlaid on the small warming trend now, so expect the '10s - '30s to resemble the '50s to '70s. During which the received proto-climatologist Climate Catastrophe Consensus was wailing about the return of the Ice Ages.

The effects of CO2 on any 'temperature trends' outside a sealed laboratory glass jar remain undetectable.

Brian H | April 3, 2011

As for glaciers and ice sheets, Captain Vancouver found such 'fjords' as the Prince William sound to be blocked by glaciers 200 yrs ago. The ice had receded many miles before the first ICE car sputtered into existence. They (mostly) continue that trend.

And ice melt is the last thing these guys are worried about: .

As for Greenland/Antarctica, the trends are mixed, with coastal areas shedding and interior areas gaining or stable. Even strong warming takes thousands of years to seriously cut into those huge masses.

Sudre | April 3, 2011

Sounds great Brian. I don't think I've ever said it's the ICE cars. I just wanted you to admit it is warming, which you just did.

Timo | April 3, 2011

No, I mean worse.

"historical boom times" does not reflect current state of humanity.

Paleoclimatologist have shown clear correlation on CO2 levels and earth temperatures, so that's that.

From your second message:

How about that North-East Passage opening up? What does that tell you about northern ice sheets?

About icebreakers: That's winter. Whole year was record warm, temperatures rising way over +30C in nearly all of Finland. Some parts got as high as +37C. In winter we got here genuine snow storms, snow more than ever before in recorded history in southern parts of Finland, but not any lower than usual temperatures. Gulf of Finland freezes over every winter, that's just normal. If it doesn't then there is something wrong.

dashrb | April 3, 2011

Timo, I'm with you, but in light of this flowchart: it might not useful to continue the "discussion". :-)

Timo | April 3, 2011

Hah. :-D. I need to put that onto wall in my workplace. Nice find.

And yes, discussion about that topic is terminated. I just hope that Brian H does the same (in all future comments too).

VolkerP | April 4, 2011

Hello all,

seems I triggered a little bomb here. I would like to come back to topic.
R134a is HFC not CFC. It is not dangerous to the ozone layer but it is a powerful greenhouse gas.

Why not use R744 (CO2) instead. Yes CO2 is a greenhouse gas, too, but several magnitudes less effective as R134a.
Using CO2 requires the AC to operate with higher pressures, thus increasing cost by approx US$ 200.

I vote for the Model S using R744. Any bystanders? Arguments pro and contra? Something I missed?

Volker.Berlin | April 4, 2011

I am with VolkerP, and that's not just because of his name. But it may be related to the fact that I am in Europe.

Kallisman | April 4, 2011

There are other ways to transfer heat too. Like thermoelectic elements. No gas used at all, so no leaks.

Brian H | April 6, 2011

Last word to Timo: the paleoclimate "correlation" runs the wrong way: first warm, then CO2. Ocean outgassing is the probable explanation.

searcher | April 7, 2011

Talking about "clash of the titans". You guys had my head spinning with all that tecnical stuff. Much further confirmation that I sure can't hang with or wont try to with you guys on techno stuff. Just will keep on asking questions for the most part. Great discussion fellows.

Roblab | April 9, 2011

Where in the real world does anybody, ANYbody, try to push an automaker or refrigerator maker or home air conditioner maker into what kind of refrigerant to use? I go to the Toyota dealer. "I want to buy the Lexus over there, but I want Toyota to use CO2 instead of R134a". Right. You go to buy a new refrigerator. "Nope, can't do it unless you change out the R134a to CO2".
Laugh you out of the store.

Volker.Berlin | April 10, 2011

Roblab, not here in Germany. Of course, you can only choose from what's on the offer, but people over here tend to base their decision for one product or another at least in part on factors like the refrigerant used. The impact of this detail on the final decision for a particular product is probably more significant when choosing a refrigerator, and far less significant when choosing a car, but it is precisely the impetus that is needed to drive manufacturers of goods into a certain direction. For instance, you cannot buy a Volkswagen Golf Hybrid, but you can buy a Toyota Prius instead, and that will make Mr. Winterkorn think twice.

I agree we do not have this choice in case of the Tesla Model S. There simply is no competitor (but only today). :-)

Brian H | April 10, 2011

CO2 was never used as a refrigerant. CFCs are Carbo-fluoroCarbons. They are extremely stable and non-toxic, which is why they were used so widely.

And still should be. The "ozone chemistry" that was the basis of the ban is turning out to be very dubious. Somebody made reeaalll big bucks on the switchover, though.

VolkerP | April 11, 2011

CFC is for Chloro-Hydro-Carbons. Google the Montreal protocol for a successful story of the economically developed countries agreeing on changing AC+thermal insulation technology.

Google Greenfreeze. Industry doubted the possibility to build a CFC free refrigerator until Greenpeace demonstrated it. I compare that to Detroit denying the market possibility of EV until TESLA arrived.

Wanting TESLA to pioneer on AC technology, too - that may be a little bit to far to stretch. But hell, why not ask? Show them that there is demand?
Would be a nice point for a "truly green" car as some people (surely not all!) will judge the Model S by that benchmark.

Douglas3 | April 11, 2011

That's Chlorofluorocarbon, actually.

Brian H | April 12, 2011

Ya, sorry. Little mental short-circuit on the name.

The Montreal Protocol was a mistake, based on weak science and excessive extrapolation, plus the "Precautionary Principle" plus a huge new revenue stream possibility for some heavy hitters. The "Hole" has been doing its own thing ever since, with no concern for CFCs. And will continue to do so.

Douglas3 | April 13, 2011

Cite your sources.

Brian H | April 14, 2011

Not the venue for it. Visit if you want to get details. "Best Science Blog - 2010"

Tiebreaker | April 14, 2011

Science? Really? From a weatherman? Who thinks "weather" is separate from "climate"?

BEST and Muller were hired and funded to dispel the "global warming myth", but... when their study supported the existence of the global warming, he was dismissed by the sceptics, Watts included.

t7n7 | April 14, 2011

Whatever Roblab said... +1

Laugh you out the store!

Some of the stuff on this forum is ridiculous. I'm sure the techs at Tesla are getting a good laugh at this.

Ya ok.. Anything else? Hmm recycled rubber tires please. Lmao.

Tiebreaker | April 15, 2011

Yeah, I +1 that too. Can't try to force the manufacturer at the store, and can't change it overnight, I agree. But can't ignore the global picture either. Baby steps, but in the right direction. Otherwise we would still have billowing smokestacks downtown.

Volker.Berlin | February 29, 2012

Has anybody any news on this issue? I would still be interested to learn what they use (and hope it is R744 or something similarly harmless).

tomas.hutters | February 29, 2012

Mainly for curiosity's sake, but not only: It would be pretty cool (pun intended) to revitalize this:

Some attempts have been made.

Brian H | February 29, 2012

Freon (etc.) is not harmful. Like so many other eco-nitiatives, it was an "error" escalated into a world-wide highly profitable scam. The so-called Winter Ozone Hole actually occurs in darkness, so the CFCs would have been unable to do anything to the ozone. There's none being created by UV at that time in the first place.

It's seasonal and cyclical. Known about for decades in rough terms, but turned into a panic when first observed in satellite-detail!

Klaus | February 29, 2012

Geez Brian, really opened up a can of worms with that one. I'm guessin' Timo first then Tikiman.

Timo | February 29, 2012

I'm not going there. Brian H has already demonstrated his almost religious incapability of trusting any scientific source about what he doesn't like about environment changes. He is denialist. Not skeptic, denialist.

jkirkebo | March 1, 2012

Hopefully they will use the AC unit for heating too. The refridgeant used in heat pumps that have to work in low temperatures is usually R410. The normal AC refridgeants don't do wery well in 0-10 F temperatures.

EdG | March 1, 2012

A sales rep told me that heat is accomplished via a ceramic heater element, as in the Roadster.

Brian H | March 1, 2012

Heh. Get updated, Timo. The ban was supposed to take 20 yrs to work, but natural variation shrank the hole immediately on its own. There's lots more research out there than you know about.

Discoducky | March 1, 2012

let's see what TM uses and then we can have a good ol'fashioned debate on how bad their decision was and how we are not going to buy the car unless they change to the other kind.

Did you see the new R2D2 refrigerant? It causes you to hallucinate and see holograms of shockingly long robed princesses.

Brian H | March 8, 2012

The more you heat the seat the more power you generate to cool the seat:
Power Felt!

But(t) the cooler the seat gets, the faster heat flows from you thru the Felt, which cools the seat even faster, which sucks even more heat -- runaway cooling! You'll be frozen in place in no time ...