

California officials Thursday abruptly halted a controversial effort to slash the carbon footprint of automobile air conditioning. “Cool car” rules would have required a clear reflective glaze on vehicle windows as a way to block excessive sunlight and heat. They were adopted in June by the state’s Air Resources Board and were in the process of being finalized.

Air conditioning lowers vehicle efficiency, increasing emissions from gasoline that contribute to global warming. But law enforcement officials had expressed concerns that the coating, a spray of microscopic metal particles which block infrared rays, would interfere with the electronic monitoring of ankle bracelets on paroled felons. Wireless phone companies said the new standard could degrade cellphone signals including 911 calls. And toll road operators said the glaze could make it difficult to use the "EZ Pass" systems enabling traffic to move quickly through toll booths.

"Stakeholders raised several new issues involving performance of electronic devices as they may affect public safety," James N. Goldstene, the board’s executive officer, announced. "After listening to this input and accounting for the legal deadline to finalize the rule, today we are announcing that the AB 32 ’cool cars’ rule-making will cease."

AB 32, California’s sweeping 2006 climate law , requires the state to cut its greenhouse gas emissions by 15% over the next decade. The cool cars rule, to be phased in between 2012 and 2016, was designed to block of 60% of the sun's energy entering the interior of a car. Once finalized, the rule would have slashed 700,000 metric tons of carbon dioxide emissions by 2020, the equivalent of taking 140,000 cars off the road.Scientists say that carbon dioxide emissions are trapping heat in earth's atmosphere, which will lead to dangerous climate change.

Spokesman Stanley Young said the board would now pursue “a performance-based approach,” meaning that auto manufacturers would have to meet a standard for a specific drop in the interior temperature of vehicles, “but they are free to draw on any technology to achieve it. This could be through advanced windows that keep the sun’s heat out, but also heat-reflecting paints, different upholstery, or even fans that circulate air and keep the car cool while it is standing in the sun.”

--Margot Roosevelt

Photo: Cars and trucks choke California freeways and, especially in summer months, use air conditioning that cuts the efficiency of cars, increasing emissions of carbon dioxide from the burning of gasoline. Credit: Al Seib/LA Times