General Motors said this week it will cut out a climate-destroying chemical from its car air conditioners by 2013, in a first for an industry seeking greener auto coolants.

The car giant will stop using HFC-134a — a "super greenhouse gas" — in all new Chevrolet, Cadillac, Buick and GMC models made in the United States, and replace it with a climate-friendlier coolant. Environmental advocates heralded the move.

"It’s a major step forward toward a global mobile air conditioning partnership that takes its environmental and sustainability obligations seriously," Durwood Zaelke, president and founder of the Institute for Governance and Sustainable Development (IGSD), a non-profit group, told SolveClimate News.

Zaelke said he expects other U.S., European and Japanese automakers to follow suit.

Alexander von Bismarck, executive director of the Environmental Investigation Agency (EIA), a Washington, D.C.-based non-profit watchdog, called the decision "the beginning of the end for an entire class of greenhouse gases."

‘Biggest Climate Opportunity’

HFC-134a is 3,830 times more potent a greenhouse gas than carbon dioxide, with a lifetime of 14 years in the atmosphere, according to scientific research published in the Proceeding of the National Academy of Sciences (PNAS). 

The GM alternative, called HFO-1234yf, has a global warming potential that is four times that of CO2 and exists for only 11 days.

Also known as "super" GHGs, HFCs were developed to replace ozone-eating gases that were banished under the 22-year-old Montreal Treaty, signed by 196 nations.  So far, the treaty has retired some 100 chemicals linked with ozone destruction; but it has also stoked the production of HFCs, which are safe for the ozone but are extremely powerful greenhouse gases.

If left unchecked, the man-made HFCs could account for 28 to 45 percent of global greenhouse gas emissions by 2050, warns the PNAS findings.

In the U.S., they are the fastest-growing source of warming pollution and are predicted to skyrocket an "astronomical" 140 percent by 2020 over 2005 levels, compared to four percent growth for the nation’s total emissions, Zaelke said.

Currently, mobile air conditioning covers 40 percent of the U.S. HFC footprint. Worldwide, the sector makes up one-third of all HFC uses, with a major boost expected due to a rapid rise in prosperity in developing nations like China and India. 

Knocking out HFCs "represents the single biggest climate opportunity in the world today," especially "now that the U.S. has decided not to act this year [on climate legislation]," Zaelke said.

A Cure Worse than the Disease? 

But not all advocates see HFO-1234yf as the solution.

BeyondHFCs, a Brussels-based international network of organizations that includes EIA and is pushing for "natural" refrigerants, says adoption of HFO-1234yf would create more environmental damage. 

According to the group, tests show the substitute can cause "incalculable risks for humans" in the case of a car accident.

"The environmental impact of HFC1234yf comes when, vented into the atmosphere, it decomposes into trifluoroacetic acid (TFA) which, leached out from the atmosphere by the rain, develops a herbicide effect," the group said in a statement. 

Christianna Papazahariou, head of BeyondHFCs, called GM’s decision "to ignore all safety and environmental warnings" concerning HFO-1234yf "very worrying."

"We hope that the car industry will not suffer from a toxic dependence on 1234yf," she said.

The campaign is advocating for CO2-based systems that are "safe for passengers and the environment." For Zaelke, however, HFO-1234yf has potential to be a widespread "high-value refrigerant."

The brainchild of chemical manufacturer Honeywell, HFO-1234yf was developed in response to policy initiatives in the European Union.

EU Drives Market, Will Montreal Protocol Follow?

The EU blew open the market for greener coolants in 2006, when it passed its Mobile Air Conditioning Directive, prompting chemical gas manufacturers like Honeywell and DuPont to find climate friendly alternatives to cool off people in their cars.

The law bans the use of HFC-134a in new car models in 2011 and all new vehicles in 2017.

In the U.S., there is no such law. Advocates hope that will change once lawmakers see that GM and the industry is moving on from HFCs.

Policies have already been set in motion, though they could take years to accomplish.

In May, IGSD, EIA and the Natural Resources Defense Council petitioned the U.S. Environmental Protection Agency to remove HFC-134a from its list of approved air conditioning chemicals. Meanwhile, both national climate and energy bills introduced in Congress — the House Waxman-Markey American Clean Energy and Security Act and the Senate Kerry-Lieberman American Power Act — agreed to phase down HFCs.

But last week, Senate Majority Leader Henry Reid (D-N.V.) punted on climate action until the next Congress, and his energy-only alternative — The Clean Energy Jobs and Oil Company Accountability Act — which was introduced in the Senate on Tuesday, scratched the HFC provisions.

Advocates argue the best bet is an amendment to the Montreal Protocol that would force the phase down. The 2009 annual meeting of the protocol last year in Egypt ended without a binding agreement on HFCs, with 41 countries signing a weak "declaration of intent" instead.

At this year’s meeting in Uganda in November, Zaelke said he expects countries to rally around the reform. The U.S., EU, Canada, Mexico and island nations most vulnerable to the ravages of climate change are all on board.

"There’s a lot of momentum building," he said.

See also:

China, India Opposed To Closing $5 Billion Loophole in Kyoto Treaty

Failure of ‘Super Greenhouse Gas’ Deal Raises Stakes in Copenhagen 

Class of ‘Super GHGs’ Becoming Focus of Heightened Concern

US Policy Breakthrough on Super Greenhouse Gases, But Obstacles Remain

Study Confirms Growing Threat of Super Greenhouse Gases

International Opportunism Thwarting Rescue of Island Nations from Rising Seas

While Politicians Debate HFCs Phase-Down, Companies Innovate

Island Nations Plead for Help from Obama on HFCs

Maldives to Phase Out HCFCs, Super Greenhouse Gases, 10 Years Early