The EU banned the use of refrigerants with a Global Warming Potential (GWP) greater than 150 in all new vehicle platforms from 2011. R134a refrigerant has a GWP of 1300. For 5 years the automotive industry had been developing CO2 systems, which have a GWP of 1, but the cost, reliability, and safety, did not meet industry needs.
There is also an issue regarding credits towards the ‘Corporate Average Fuel Economy’, (CAFE), regulations requiring a minimum MPG of 34.1 for all vehicle’s by 2016.
Some OEMS will require these credits to off-set fines incurred from a non-compliant fleet. HFO-1234yf has a GWP of 4.
It has been co-developed by DuPont and Honeywell, and will replace R134a for vehicles in the next generation. There are however, some service differences, these being that all service equipment must meet J2843, J2851 VDA Requirements.
This will mean new recovery, recharge, refrigerant identifiers, and leak detection equipment. HFO-1234yf system components cannot be replaced with any other ones using a different refrigerant, or from salvaged vehicles.
Any replacement evaporator will have to meet the new standard for the proposed ISO 13043 and/or SAEJ2842. Most importantly, HFO-1234yf is mildly flammable, and all precautions used with other flammable substances will be applicable.
THE HFO/1234YF DILEMMA
On November 23rd 2012 the European commission ruled that after 1st January 2013 R134A which has been in use since 2004 as the main refrigerant for automotive a/c systems will not have type approval for manufacturing. The new gas that has been jointly developed by Honeywell and DuPont is called HFO 1234YF and must be fully adopted by manufacturers as standard refrigerant by 2017.
By the end of 2012, Daimler/Mercedes had released press statements regarding the potential flammability risks of HFO, putting the manufacturing industry into turmoil. Essentially all the time and money spent in research and development on this product will be wasted.
By February 2013 Daimler/Mercedes Benz, Audi, & BMW officially leave the HFO development program stating the concerns over vehicle safety.
Daimler/Mercedes Benz recalled the SL class (R231) built with HFO platforms with the intention of rebuilding the sold vehicles to R134A.
By June 2013 the European commission granted the manufacturers an extension for the type approval and for further safety testing of the HFO product.
In August 2013 the German safety authority (KBA) supported Mercedes Benz in their decision not to adopt HFO and this was supported by the French government’s decision to block registration of new vehicles containing HFO.
As of January 21st 2014 the European commission is preparing proceedings against any manufacturers using 134A in their vehicles.
There are then three documented proposed alternatives currently being considered:
TIFFE – (Thermal Systems Integration for Fuel Economy)
This is a joint collaboration between Fiat, Ford Germany & Denso the system offers both engine cooling and air conditioning, combining both current systems and utilising a heat exchanger. There are both positives and negatives to this system.
The positives are that a heat exchanger does not have to be mounted at the front of the vehicle for maximum airflow, but can be mounted under the vehicle allowing for more aerodynamic design concepts. The system does not require engine power. And therefore is suited for Hybrid technology vehicles it also has an academic fuel consumption of approximately 28% due to homogenous consumption.
There are also some negatives firstly the system takes three pumps to run as opposed to the current single compressor, this means that there could be future warranty and servicing implications due to this added component. There are potential problems with long term reliability due to additives that are required to be added to the system. Finally there would need to be new refrigerants potentially required to ensure system efficiency.
CO2 systems are currently widely used in large scale industrial applications. The system is efficient from an academic viewpoint and is known to be reliable. However there are major problems in producing a CO2 system small enough to fit into an automobile. Also CO2 is highly toxic to humans and the potential for leaks and seepage into the cabin of an automobile inevitable illness and even death may occur. This will take a lot of convincing to the current vehicle safety authorities worldwide and manufacturers to adopt.
This product is manufactured by Mexicem in Mexico it is designed to be a safer, less flammable alternative to HFO-1234YF. The product is still mildly flammable and although better than HFO due to current perception of HFO it would be hard to change the viewpoint of both manufacturing industry and the worldwide vehicle safety authorities. There would potentially be further safety issues further down the line with this product in regard to aftermarket servicing procedures.
Whereas R134A has a boiling point of -26c, R445A has a boiling point of -48c and so carries increased risks of cold burns to servicing personnel in the aftermarket and would be very hard to comply with health and safety legislation in the workplace.
In summary the three current proposed alternatives to HFO each have significant downsides and there is no easy short term answer. In an ideal world it would be for someone to spend a lot of money on research and development to find a brand new product.
Anyone who was able to develop this ideal product would potentially have not only worldwide sales of that product when fitted to automobiles but also increased brand credibility, revenue form refrigerant and consumables sales both in manufacturing and aftermarket servicing.
The answer does however need to be found quickly and in any event before 2017 to comply with the legislation’s currently in place.
I know that as of today, (1/2/14), currently major motor manufacturers are struggling to find solutions to this problem, and a lot of work is currently being done in R&D, but no solution has yet been found, and I will update this page with further information as I have it.