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Inside the industry-enviro partnership that scored a big climate win on HFCs

The US is now poised to curb use of super-climate-warming refrigerants, one of this century's most significant climate mitigation efforts.

Jay Stein
Jay Stein
9 min read
Inside the industry-enviro partnership that scored a big climate win on HFCs

Over the last decade, a coalition of industry and environmentalists has been quietly working to ban super-climate-warming refrigerants from home air conditioners and heat pumps. Now that work is on the verge of achieving one of the greatest U.S. climate-mitigation successes of the early 21st century.

It’s not unheard of for industry stakeholders and environmental advocates to team up to persuade governments to take action to protect the climate. But it’s much more common for the two groups to be in conflict. By cooperating, though, this coalition has racked up an impressive number of achievements in a relatively short amount of time.

At the core of the coalition is an alliance between the Air-Conditioning, Heating, and Refrigeration Institute, a trade group that represents more than 300 equipment manufacturers, and the Natural Resources Defense Council, an environmental group with 3 million members. The environmentalists are motivated by mitigating the emissions that exacerbate climate change. The industry members may also share those motivations, but they speak more of achieving regulatory certainty and being better able to compete in the international market.

For the past five years, these two organizations have hashed out agreements on a basic set of policies for regulating refrigerants, lined up associates to join them, helped to persuade Republican senators to support bipartisan legislation, and convinced the California Air Resources Board to modify its policies. Now they and other supporters are on the threshold of seeing the U.S. Environmental Protection Agency adopt the policies they’ve advocated for. With that EPA decision expected in mid-October, the coalition is achingly close to achieving its goals. It has one last group to win over: building code officials from counties and municipalities all over America.

Our story starts in Kigali

In October 2016, representatives from the nearly 200 countries that signed the Montreal Protocol converged on the Rwandan capital city of Kigali. Their goal: to approve a new amendment to the international agreement on phasing out substances that deplete the atmospheric ozone that protects all living things on earth from harmful ultraviolet radiation.

The Kigali Amendment was designed to phase down the production and use of hydrofluorocarbons (HFCs), which are widely used as refrigerants in air conditioners, heat pumps, refrigerators and freezers. HFCs were introduced in the early 1990s as a substitute for chlorofluorocarbon refrigerants, a key driver of ozone depletion that was targeted for phaseout by the original Montreal Protocol.

But with an atmospheric-warming potential that’s thousands of times greater than carbon dioxide, HFCs are becoming a serious contributor to climate change. In theory, HFCs are not supposed to be entering the atmosphere in large quantities — but in practice, they’ve become a significant threat due to leakage from operating and discarded equipment.

The Kigali Amendment doesn’t target HFCs for total elimination, as international policymakers expressed concern that there could be some essential uses, such as inhalers for asthma, for which suitable alternatives could not be found. But it does call for a steady scaling down of HFC production and use to a minimal level by 2036.

The amendment largely leaves the methods of this phasedown up to individual governments, however. After its approval, the coalition led by the Natural Resources Defense Council and the Air-​Conditioning, Heating, and Refrigeration Institute began to lobby for ratification in the U.S. Senate and codification into U.S. law. That’s when the complications began to emerge.

The plot thickens

Just weeks after the Kigali Amendment was approved, the U.S. elected Donald Trump as president. This created an immediate roadblock to the coalition’s efforts to gain federal approval of an international agreement that aims to limit a chemical’s production and use, not because of its direct impacts on health but because of its influence on climate change.

The Kigali Amendment accounts for HFC refrigerants using a metric labeled global warming potential, a multiple of how much more atmospheric heat a given refrigerant traps than carbon dioxide. For example, the GWP of R-410A, the current standard air-conditioner and heat-pump refrigerant, is 1,924. That means that a pound of R-410A in the atmosphere will trap nearly 2,000 times as much heat as a pound of carbon dioxide.

To meet the requirements of the Kigali Amendment, the EPA would need to regulate refrigerants based on their GWP. But a U.S. appeals court ruling in 2017 essentially forbade the agency from doing so. As a result, the coalition advocated for legislation that would enable the EPA to issue such regulations — an effort that found little traction in a Senate controlled by a Republican party led by a president who denied the reality of global warming.

The coalition’s efforts were also subjected to more complexity due to the physics of low-GWP refrigerants. Gases with a molecular structure that decomposes rapidly when exposed to oxygen don’t have as high a GWP since they don’t remain in the atmosphere as long. However, that very same reactivity to oxygen makes these chemicals more flammable, thus posing a greater risk for common use. Years before the adoption of the Kigali Amendment, researchers led by scientists from the National Institute of Standards and Technology were unable to identify a refrigerant for use in residential equipment that was both nonflammable and with a low GWP.

Eventually, those researchers came to accept that in the future, residential refrigerants would be flammable, but not very flammable. Many of the best candidates were described as “mildly flammable,” meaning they can be ignited, but only at certain refrigerant-to-air ratios unlikely to come about in the course of leakage, or only when exposed to open flame, as opposed to a heating element in a household appliance like a toaster or hair dryer. One example of a mildly flammable refrigerant is ammonia, long used in industrial refrigeration systems. You may well have some under your kitchen sink.

Another group of researchers, under the direction of the Air-​Conditioning, Heating, and Refrigeration Institute and others, went to work developing new systems to enable the safe use of mildly flammable refrigerants. This work led to soon-to-be-released air-conditioning and heat-pump systems equipped with sensors to detect leaks of the mildly flammable refrigerants they contain, which can trigger fans to dilute any leaking refrigerant with indoor air to prevent ignition.

Safety systems like these significantly reduce the threat posed by appliances that use mildly flammable refrigerants. But their widespread acceptance still faces a major obstacle: state and local building codes. Contractors must get the approval of a local building department to install all but the smallest of air-conditioning or heat-pump systems.

At present, however, few building departments are prepared to approve a system charged with mildly flammable refrigerants. Most current codes don’t allow mildly flammable refrigerants to be used in homes or businesses, and they don’t incorporate standards for the new safety systems that go with them. New building code updates that enable officials to approve systems containing mildly flammable refrigerants are on the way, but it’s going to take time for them to be adopted by local building-code jurisdictions across the country.

California, the land of opportunity

In 2016, before the Kigali Amendment was signed, California passed a law authorizing the California Air Resources Board, the primary state agency responsible for protecting the public from air pollution, to regulate HFC refrigerants. CARB followed up soon thereafter with the nation’s first proposed limits on refrigerants in newly manufactured residential and light commercial air conditioners and heat pumps (but not room air conditioners, which are regulated separately). CARB proposed limiting the refrigerants in those systems to a GWP of less than 750 starting January 1, 2021. That 750 GWP number represented progress, as it would reduce by nearly two-thirds the GWP of residential and light commercial refrigerants. Importantly for the industry, there were several refrigerants under development that could clear that bar, although most of them were mildly flammable.

CARB’s proposal, the first of its kind in any state, got the attention of both the industry and its coalition partners. Nearly everyone in the coalition expected that whatever California did would set the standard for regulation of residential refrigerants and help determine how much of the rest of the country followed suit, whether or not the Kigali Amendment passed into U.S. law. As Helen Walter-Terrinoni, the Air-Conditioning, Heating, and Refrigeration Institute’s vice president for regulatory affairs, told me at the time, “For the industry right now, California is everything.”

The coalition initially supported CARB’s proposal, asking only to push back the start date by two years. In 2020, though, it became apparent that due to the pandemic and other factors, California building codes wouldn’t be ready to accept mildly flammable refrigerants by 2023, pushing the industry group to ask CARB to delay the start date for its regulations to 2025. NRDC’s leaders again decided to support their counterparts at the Air-Conditioning, Heating, and Refrigeration Institute. In December 2020, CARB granted the coalition its request, and California will ban refrigerants for residential air conditioners and heat pumps with a GWP over 750 starting in 2025.

The phasedown goes national

After years of fruitlessly lobbying senators and the Trump administration to ratify the Kigali Amendment, a breakthrough occurred in early September 2020. That’s when two Republican senators announced they would join Democrats in supporting a bill that encoded the Kigali Amendment into U.S. law, reversing a stance that had stymied the passage of an energy bill containing a similar amendment earlier that year.

As the House had already passed such a bill, the only obstacle still remaining was gaining the president’s support. Biden made it clear in his campaign that he would sign such a law, but the coalition didn’t have to wait for his inauguration. When Trump signed the Covid relief and omnibus spending bill with just weeks left in his presidency, buried in its 5,593 pages was the American Innovation and Manufacturing (AIM) Act, which largely followed the goals of the Kigali Amendment. The HFC phasedown was now U.S. law — and most importantly, a law that authorized the EPA to regulate HFCs for specific applications and types of equipment.

The coalition quickly went to work to decide which policies to endorse that would enable the EPA to meet the goals of the AIM Act. In April, the Air-Conditioning, Heating, and Refrigeration Institute and the Natural Resources Defense Council, in separate but similar petitions, both requested that the EPA enact the same regulations recently enacted in California for residential air conditioners and heat pumps. They were joined in their petitions by other organizations including the Environmental Investigation Agency and the Institute for Governance and Sustainable Development.

It’s widely expected that the EPA will grant this request, according to Christina Theodoridi, a technical analyst with the Natural Resources Defense Council. “We expect the EPA will accept our petition because it’s noncontroversial and already established in California.”

The endgame

Assuming the EPA rules as expected, that leaves one last group for the coalition to win over: the building-code officials working in thousands of jurisdictions that range in size from entire states to individual counties and municipalities.

Some states such as California have statewide building codes. In Colorado, by contrast, most counties and many municipalities administer their own codes, varying from Denver (population 740,000) to San Juan County (population 700). To complete its work, the coalition needs to persuade these agencies to update their codes to approve mildly flammable refrigerants as well as ensure the accompanying safety systems are properly installed.

So far, the coalition has submitted proposals to several technical committees that many building code jurisdictions look to for guidance. According to Theodoridi, “those proposals were passed by the committees unanimously.” If all goes well, starting in 2024, those code updates will go to individual building departments for adoption.

The most advanced jurisdictions typically take about a year to complete this task, which would enable them to have their codes ready in alignment with California’s 2025 target for enactment, and potentially with the EPA’s federal regulations as well. As for the laggards, it can take them a decade or more to adopt a new code edition.

In the meantime, the coalition is looking into a variety of means to speed up these code updates, preferably at the state level. Both the Washington State Building Code Council and the Texas state legislature recently took action to approve the new refrigerants, and the coalition is encouraging more statewide organizations to follow their lead.

Eventually, however, the Air-​Conditioning, Heating, and Refrigeration Institute and its partners will need to find a way to engage with the thousands of building departments that will require additional implementation support beyond what their respective states provide. With all the obstacles the organization has overcome to get to this point, it will find a way to muddle through this challenge somehow, but there’s bound to be plenty of confusion and frustration before it’s done.

Even with the building-code issue still far from resolved, some coalition members are already thinking about what comes next. Some environmental advocates are wondering whether California’s current threshold of 750 GWP for residential refrigerants is too high and are considering inviting their industry partners to support a lower threshold of perhaps 500 GWP or lower.

Others are thinking about moving the coalition’s focus beyond refrigerants. “I’d love to replicate what we’ve done with refrigerants on the energy efficiency side,” said AHRI's Walter-Terrinoni, targeting the significantly higher greenhouse gas emissions associated with the electricity this equipment consumes than the refrigerants they may leak. This could be a fitting next step for a partnership that’s shown what can be accomplished when environmental and industry groups work together.

(Article image courtesy of Ashkan Fourozani)

climate changeHFCair conditioningrefrigerationTrump administrationKigali Amendment

Jay Stein

Jay Stein is one of America's leading energy technologists, an entrepreneur, and thought leader. He is affiliated with E Source where he holds the title Senior Fellow Emeritus.