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Automotive AC Makers Are Sweating

The regulation of hydrofluorocarbons looms in Europe -- and may be copied by California. Will CO2 keep us cool instead?

By Peter Fairley

Monday, May 08, 2006

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In the 1990s, air conditioning suppliers switched from the chlorofluorocarbon Freon to an equally troublesome hydrofluorocarbon called R-134a; while easy on the ozone, R-134a is a greenhouse gas that's 1,300 times more potent than CO2.

Automotive equipment maker Delphi will opt for this trial-tested carbon dioxide air-conditioning system, if more experimental hydrofluorocarbon refrigerants don't pan out. (Photo courtesy of Delphi.)

The impact has been most acute in automotive applications, where refrigerants often leak out. Indeed, by 2010, such leakage will contribute more than 4 percent of the total climate change impact from motor vehicles. Add in the extra fuel consumption to run the AC, and AC's share rises to 7 percent.

Little surprise, then, that the European Union decided this January 31 to begin phasing out the use of R-134a in new model cars beginning in 2011, and that regulators in California are preparing to follow suit. Until this spring, the most likely replacement looked to be novel high-pressure systems employing, ironically, CO2 as the refrigerant. Behr GmbH -- Europe's leading AC supplier for cars -- announced last month that they would begin selling CO2-based systems ahead of the EU's 2011 deadline.

But Behr's competitors, such as Troy, MI-based Delphi and Germany's Robert Bosch GmbH, have been backing away from CO2 since February, when DuPont and Honeywell unveiled new hydrofluorocarbon refrigerants that may be clean enough to squeak by the regulators. According to the chemical companies, the new kinds of hydrofluorocarbons are no more than 150 more potent as greenhouse gases than CO2 -- the limit set by the EU for auto refrigerants after 2011. What's more, these refrigerants can be dropped into existing AC equipment. "The prospect of having a new drop-in refrigerant that would satisfy the 2011 legislation is incredible -- it's enormous," says Stefan Glober, director of engineering for Delphi's thermal and interior division.

Many questions remain for both options, however. The new hydrofluorocarbon-based refrigerants offered by DuPont and Honeywell must complete a host of long-term tests, including for the stability of the compounds under heavy use and for toxicity. That could take at least three years. And it's unknown how much the new refrigerants will cost to manufacture. This means that AC manufacturers must also continue to develop their new CO2 systems. "These alternatives have appeared relatively late. That's the dilemma we're in right now," says Glober.

The CO2 systems have their own hurdles. One is detecting leaks: cheap, effective CO2 sensors don't exist yet. "That's a huge headache," says Glober. Another is cost. And it's here that Behr and its competitors part ways. Glober says the industry consensus is that the first CO2 systems will sell for €150-200 more than conventional AC systems, doubling their costs. Behr, in contrast, says it will be able to keep down the added cost to less than €100 in the first-generation system and half that by 2015 -- sums that the firm predicts will be justified by higher performance.

Comments

  • to freon or not to freon
    Frankly, I never bought into the whole 'danger to the ozone shield' theory. Chlorofluocarbons are very heavy molecules, and the 'ozone holes' reported tend to occur exactly where they would naturally. But this makes loads of money for activist groups--and researchers.
    Rate this comment: 12345
    Guest (kitk)
    05/08/2006
    Posts:1
    • Then obviously...
      Researchers of all stripes fabricated results that indicated increased concentration of CFC's in the upper atmosphere.  They also has to then demonstrate reaction pathways for the distruction of ozone that really couldn't occur.  It is amazing how much some people wish to disbelieve hard science, are you also a proponent of intelligent design?
      Rate this comment: 12345
      Guest (Ynot)
      05/08/2006
      Posts:1
    • [no subject]
      The science of ozone depletion is pretty well established.  In fact, Roland and Molina, who theorized it back in 1973, have now, many years later, gotten a Nobel prize in chemistry for their work.  But back in the 1970s, they were ridiculed by the CFC industry.  For a nice description, you could look at the book: Protecting The Ozone Layer: The United Nations History
      by Stephen O. Andersen. 
      Rate this comment: 12345
      Guest (Greg)
      05/09/2006
      Posts:1
  • Absorbtion Cycle?
    I know of at least one company that has been working on an ammonia cycle refrigerant system for cars using waste heat from the engine which for obvious reasons makes all kinds of sense.  The major drawback is it doens't act quickly - you have to wait perhaps a minute for it to start working as the engine warms up.  Personally I wouldn't care particularly with the energy savings it offers.

    I've wondered for nigh on 35 years why this has never caught on, but then I'm an engineer not a politician or capitalist pig.
    Rate this comment: 12345
    Guest (Jeff)
    05/08/2006
    Posts:1
    • absorbtion
      would you share the names of the companies dealing in ammonia, great refrigerant with nasty reprecussions
      Rate this comment: 12345
      Guest (brandon)
      05/09/2006
      Posts:1
    • Absorbtion cycle's difficulties
      The need for a substantial condensor and the sensitivity of the system to vibration troubles has killed this idea.

      Long haul trucking would be the market to target.

      As with any new technolgy the mass produced automobile is the LAST market to tackle.
      Rate this comment: 12345
      Guest (blert)
      05/09/2006
      Posts:1
    • Ammonia cycle
      I also would like whatever good and bad information you have on the ammonia cycle refrigerent system.
      Rate this comment: 12345
      Guest (Randy Dutton)
      05/10/2006
      Posts:1
      • Residential unit
        I am beginning work on combining a propane fuel cell with an Absorbtion unit for domestic use.  Teh overall efficiencies should be attractive and the extra waste heat will provide hot water.  Any help along these lines would be appreciated, ivank2005@comcast.net
        Rate this comment: 12345
        Guest (Ivan)
        05/31/2006
        Posts:1
  • Extra fuel consumption
    I am puzzled by the "extra fuel consumption " argument. What would drivers do by hot weather ? Drive with fully open windows : which would cause the same - or higher - extra fuel consumption.

    In addition regulators and environmentalists never take in consideration the merits of air conditioned on driving safety and improved health conditions for babies and old people.
    Rate this comment: 12345
    Guest (Grunchard)
    05/11/2006
    Posts:1
  • What ever happened to ROVAC?
    Years ago in Popular Science I remember reading about an A/C system that took interior compartment air and compressed it (like with engine turbo chargers) then ran the pressurized (heated)air through a cooler (like a turbo charger intercooler) and when the "now cooler" pressurized air was released back into vehicle interior it expanded and was cooler. What ever happened to that concept? It's something to do with the old supercharger sitting in the garage!! =];-)
    Rate this comment: 12345
    Guest (Poly)
    05/11/2006
    Posts:1

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