Volkswagen follows Daimler in opting for CO2 refrigerant


Volkswagen, the world's third largest carmaker, has joined its compatriot Daimler in deciding not to use a new air-conditioning (A/C) refrigerant developed by U.S. firms Honeywell and DuPont in its cars, choosing a CO2-based system instead.

Volkswagen plans to roll out carbon dioxide-based air conditioning systems throughout its entire fleet instead of the Honeywell/DuPont refrigerant called HFO-1234yf, which was created to meet more stringent environmental regulation.

Daimler engineers testing the flammability of HFO-1234yf discovered that it could spark a fire under the hood of the car strong enough to spread throughout the vehicle. In the process, the chemical emits a highly toxic gas when burning.

"Over the course of more than two decades in development, CO2-based automobile air-conditioning systems have experienced a number of performance, cost, safety and environmental issues that have made them a less attractive alternative to automakers globally," Honeywell said in a statement, after Daimler decided on Thursday to develop a new CO2-based A/C system.

The U.S. duo invested heavily in bringing to market the refrigerant, which conforms to a new EU directive. Due to its high price, costing 10 times as much as the current common refrigerant R134a, it's only commercial application is in cars.

Critics of carbon dioxide as a refrigerant argue that it requires a comprehensive and costly redesign of A/C systems, can cause drowsiness among drivers if it leaks into the passenger cabin and may trigger higher indirect carbon emissions since it potentially requires more fuel to operate.

But German firms have made significant investments in CO2 air conditioning systems, and Berlin’s federal environment agency (UBA) last month called on the EU to delay a 1 January 2013 deadline for moving to cleaner coolant systems by three years, if Daimler switched over to a CO2-based system.

While Daimler sold only about 1.5 million Mercedes and Smart cars last year, VW's decision means Honeywell and DuPont have lost another 9.3 million vehicles worth of business.

A spokesman for Volkswagen declined on Friday to say when exactly Volkswagen would begin to use carbon dioxide in its A/C systems, but ruled out any possibility that it could begin this year.

Volkswagen Chairman Ferdinand Piech had signalled in November that his group – consisting of brands that include Audi, Porsche and Skoda – would not use HFO-1234yf because of its flammability.

Unless greenhouse gas emissions are reduced by 80-95% on 1990 levels by 2050, scientists believe that a catastrophic heating of the planet by over 2°C will be unavoidable this century. The contribution of F-gases - which are non-CO2-based greenhouse gases - to global warming is contested, but tangible. F-gases are mostly found in refrigerant and cooling systems.

The UN's Intergovernmental Panel on Climate Change has estimated the built-up presence of F-gases in the atmosphere at 17% of the total human contribution to climate change. F-gases are covered by the Kyoto Protocol, which commits the EU to reducing its greenhouse gas emissions by 8% between 2008 and 2012.

In 2006, an EU regulation on air-conditioning systems and 'stationary' industrial applications tried to improve the containment of leaks, recovery of used equipment, labelling of products, reporting of emissions data to the EU and phasing out of some F-gases, such as SF6 (magnesium dye-casting). But its implementation was patchy.

A separate 'Mac Directive' in 2006  phased out F-gases with a global warming potential (GWP) of more than 150 for used in 'mobile' car air conditioning systems from 2017. The GWP scale measures greenhouse gas trapped in the atmosphere relative to a unit of carbon dioxide (standardised to 1). The directive also banned HFC-134a, which had a GWP of 1430 and led to an industry-wide shift to a less damaging HFC called HFO-1234yf, with a GWP of 4.

  • 24 April 2013: European Parliament’s environment committee to vote on CO2 in cars proposals
  • May 2013: European Parliament committee vote on CO2 in Vans
  • 2014: Proposed deadline for EU decision on 2025/2030 targets
  • 2015: 130 grams of CO2 per km target to be enforced across Europe
  • 2020: Proposed deadline for 95g/km target for cars
  • 2025: European Commission could impose another milestone on the road to decarbonsiation by 2050
  • 2030: European Commission could impose another milestone on the road to decarbonsiation by 2050

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