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Light vehicle air conditioning (A/C) systems in Europe are moving to a new refrigerant, in response to concerns about the environmental effects of the current refrigerant. Air conditioning systems affect the environment directly through leakage and indirectly in terms of fuel consumed to run the A/C system. A new EU regulation (F-Gas Directive 2006/40/EG) for mobile air conditioning systems addresses the direct effects of refrigerant release.
This is not the first time vehicle A/C systems’ refrigerant has changed. Up until the mid-1990s, R12 was the refrigerant of choice, until environmental concerns drove the introduction of a new and current refrigerant, R134a. Now, R134a is being targeted because of its global warming potential, although it is a big improvement compared to R12.
DuPont and Honeywell developed HFO-1234yf (YF) jointly, in response to the 2006 EU directive requiring all new vehicles sold in the EU be equipped with low global warming potential (GWP) refrigerants. The limit was set at a GWP value of 150, which YF easily meets. Further, it decomposes in the atmosphere in about eleven days. Life Cycle Climate Performance (LCCP)—a model certified by the US Environmental Protection Agency (EPA)—calculations confirm it as “the most sustainable refrigerant for worldwide use.”
The European Commission has mandated that R134a refrigerant cannot be used for newly certified light vehicles sold in the European Union. Originally, this mandate was for vehicles certified as of 1 January 2011. Because the new refrigerant was not readily available, this deadline was extended to 1 January 2013. Any newly certified vehicle from 2013 onward must use a refrigerant that has a GWP value less than 150. Starting in January 2017, all newly registered vehicles must use an alternative refrigerant. Notably, the European Union is the only market with such a regulation. In the United States, an EPA credit is available for vehicles using YF, but only General Motors (GM) has so far pursued that, and there seems no great impetus for other OEMs to follow in the near term.

Source: IHS 2013 New Refrigerant Vehicle Production Forecast-2013.This database is maintained at the OEM, vehicle platform, and vehicle model level, and takes into account vehicle sales destinations to best determine new refrigerant adoption.
By 2018, only 60% of European-produced light vehicles will use the new refrigerant. Vehicles sold outside the European Union will continue to use R134a, or perhaps something else.
In North America, as there is no mandate to use an alternative, we only see a slow rise in use for those companies that want to claim the available EPA credit. Some US states, however, are considering regulations that will force adoption of low-GWP refrigerants. For other countries, there is no mandate to use an alternative, and we don’t expect one in the near term. Thus, the obligation to use an alternative only comes about for vehicles being exported to the European Union. Still, recent G20 agreements involving the United States and others would reduce production and consumption of hydrofluorocarbons (HFCs), which will encourage adoption in the medium term.
HFO1234yf was generally accepted as the new refrigerant, but now there is some doubt. It is well-documented that Daimler and some other German OEMs and authorities believe YF is not safe because of flammability. In response, Germany has approved some Daimler vehicles to continue to run on R134a, contrary to the EU directive.
The European Commission had threatened legal action against Germany for failing to fully implement new emission rules for refrigerants, and may also sanction Daimler for not following those rules by shifting to 1234yf or an equivalent on recently certified vehicles. In late September, the commission sent a formal request to Germany “to take the necessary actions to apply the EU directive on mobile air conditioning. Germany now has two months to comply with the commission's request. If they fail to do so, the commission may decide to refer the matter to the European Court of Justice.”
The remaining OEMs, including GM and Toyota, have publicly stated their support for YF, and claim they believe it to be safe.
It is all about risk. The SAE Cooperative Research Project (CRP) theoretical model for such is still valid in terms of that risk, and it supports the assessment that HFO1234yf is a safe and effective automotive refrigerant. The SAE CRP model concluded the risk of exposure to or risk of being injured from ignition of YF have probabilities of about 10–10—less than the chance of being killed by lightning of 10–6.
The additional cost of the new YF refrigerant is in the EUR30-50 range, but there are no major additional system costs, mainly since it is a drop in for existing systems running at similar pressures, using the same heat exchangers and compressors. YF systems are slightly less efficient than the ones they replace, and the additional use of an internal heat exchanger is needed to make that up. Some OEMs will fit that to maintain performance, while—since the performance change is minimal—others will not, especially for smaller cars.
The inherent cost of the manufacturing process for YF is higher than R134a, so there will be some premium to pay for many years. On the other side, the average amount of refrigerant required in a modern system is declining, from above 750cc to around 500cc.
There is another factor here, and that is scale volume. Since—for now—only cars sold in the European Union will use YF, we will have dual filling stations on vehicle production lines, where cars sold in most of the rest of the world will continue to use R134a. That is suboptimal and increases costs.
While new refrigerant costs are high, other alternatives will be sought. OEMs may encourage this, for obvious reasons. From a fluorochemical perspective, suppliers like Arkema and Mexichem want to produce YF themselves, but also an alternative refrigerant, as demand for R134a declines. AGC has entered into agreement with Honeywell to manufacture YF in Japan starting in 2015.
Historically, during changes in principal refrigerant, blends have played a role, and we may see that again. Mexichem’s AC6 (R-445a) is such a blend, composed of a mix of R134a, HFO1234ze, and CO2, and is attracting some industry attention, but so far, there is no OEM committed to use it.
R152a refrigerant may also find a niche market. Originally dismissed on flammability grounds, this issue is largely negated through the use of a dual loop system, so the refrigerant does not enter the cabin. It has good efficiency, and its costs would be substantially less than YF. This may be attractive for high temperature/high humidity countries outside Europe.
Daimler, BMW, and the Volkswagen Group have stated a preference for CO2/R744 systems, and Daimler and a number of suppliers have recently announced new development for such systems. In terms of bare GWP numbers, (CO2 = 1, HFO1234yf = 4, R134a = 1300), CO2 is superior.
All things considered, CO2 is likely to be the long-term future refrigerant, especially as we move toward electrically driven vehicles using heat pump systems. The real issue here is the near term, and especially starting in 2017, when all newly registered vehicles in the European Union will have to use a refrigerant other than R134a.
By David Smith-Tilley, director, component forecasts & analysis
Posted January 12, 2015


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