The world wants air conditioning. Can we stop it from killing the planet?

Introducing Grid Health, our new weekly health and policy newsletter

The world is obsessed with air conditioning. How can we stop it from killing the planet?

Keeping the world cool is only making it hotter.

It is one of climate change’s vicious little circles, where warming the planet requires more cooling, which generates more warming. This summer has seen dramatic heat waves everywhere from Iraq and India to France and the United Kingdom, and virtually every year for the foreseeable future is likely to reshape the grim top-ten list of warmest years on record.

“The market for cooling is on a rapid growth trend, driven by climate change, population growth, urbanization and income growth,” said Toby Peters, the University of Birmingham’s engineering and physical sciences professor in cold economy. “In the absence of any intervention, the [greenhouse gas] emissions from cooling may more than double by 2050.”

According to a 2018 report from the International Energy Agency (IEA), the number of air conditioning units will more than double between 2020 and 2050, reaching two-thirds of the world’s households by midcentury — half of them will be in China, India and Indonesia. Through 2050, building cooling will account for 37 percent of all the growth in electric demand.

ADVERTISEMENT

Air conditioning, as well as refrigeration, relies on hydrofluorocarbons (HFCs). Both types of cooling use HFCs to absorb heat in a room or inside a refrigerator, and essentially remove it through evaporation. When the HFCs themselves are released as a gas into the atmosphere through leakage, they act as powerful greenhouse gases — meaning it is important to replace them with some climate-friendly alternatives, like another class of chemical called hydrofluoroolefins (HFOs) or even carbon dioxide itself.

“Hydrofluorocarbons are in fact the fastest-growing source of GHG emissions in the world due to the increasing global demand for space cooling and refrigeration,” Peters told Grid. “Cooling already accounts for more than 7 percent of all global greenhouse gas emissions.”

As the world warms, some parts of the world will see huge demand during peak times — for example, while cooling took up just 16.1 percent of peak electric loads in the Middle East in 2016, by 2050 that number will be 31.4 percent (though improved efficiency appliances could reduce this). In India, that 2016 to 2050 jump will be from 10.5 percent all the way to 44.1 percent.

“With rising incomes, air conditioner ownership will skyrocket, especially in the emerging world,” said Fatih Birol, executive director of the IEA at the time of the report’s release. “Growing electricity demand for air conditioning is one of the most critical blind spots in today’s energy debate.”

The most successful treaty ever

The world faced a problem similar to the HFC issue before — and defeated it.

ADVERTISEMENT

The Montreal Protocol, crafted in 1987, was designed to reduce the use of gases that were depleting the ozone layer, in particular chlorofluorocarbons (CFCs). By some accounts, it is among the most successful international treaties ever, signed by every country in the world. The parties to the protocol have phased out 98 percent of their ozone-depleting substances.

But its success had a side effect: the rise of HFCs to replace the CFCs. HFCs don’t deplete the ozone but have “global warming potential” — meaning the ability to trap heat in the atmosphere and warm the planet — of hundreds to thousands of times that of carbon dioxide. And with more and more refrigeration and cooling needed as countries develop and the world warms, there are a lot of HFCs out there.

Most of those emissions — about 80 percent, according to Peters — are indirect, meaning they arise from the electricity used to run cooling devices or the fuel in refrigerated trucks and other transport. But that leaves 20 percent that are direct emissions of HFCs themselves, leaking from air conditioners and refrigerators both during use and at the end of their lives when they are scrapped. The Kigali Amendment to the Montreal Protocol plots a course to phase down use of HFCs in favor of HFOs — which have much lower global warming potential — or other alternatives, so eventually there will be no more HFCs left to leak.

Ratifying a global agreement to phase out HFCs could help the world avoid as much as one-half a degree Celsius (0.9 degrees Fahrenheit) of warming by 2050. While the numbers may seem small, the effect could be astonishing, given the current warming of around 1.2 degrees Celsius above preindustrial levels and the global push to keep warming to 1.5 degrees Celsius to avoid catastrophic consequences.

In simpler terms, the Kigali Amendment takes direct aim at one of the more vicious feedback loops caused by climate change. And though the U.S. helped push for the Kigali Amendment’s adoption in Rwanda in 2016, it has yet to officially ratify it. That’s where the Senate comes in.

ADVERTISEMENT

“The Kigali Amendment is a win-win-win: it’s good for American industries’ global economic competitiveness, it’s good for consumers’ pocketbooks, and it’s good for our planet,” said Sen. Tom Carper (D-Del.), when the amendment made it out of committee in May. Though the full Senate has yet to schedule a vote, there is hope it could happen soon. Approval by the Senate would require the support of a two-thirds majority, or 67 senators — clearing the way for formal ratification by the Biden administration.

The Senate could put the U.S. on a path to fixing its air conditioning problem

With all that cooling on the way, the Kigali Amendment looms as a potential climate game-changer. To date, it has been ratified by more than 130 countries and territories, including some of the biggest HFC emitters, like the European Union, Japan and China — but not the United States.

“They are a huge manufacturer and exporter of HFCs and also have invested heavily in low [global warming potential] alternative technologies,” Peters said. “Therefore, U.S. ratification will drive the transition to next-generation climate-friendly alternatives.”

To be fair, the U.S. is already reducing its use of HFCs even absent Kigali ratification. The American Innovation and Manufacturing Act, was passed as part of a larger appropriations bill at the end of 2020, and it instructed the Environmental Protection Agency to lead an HFC phasedown that matches the Kigali requirements. But joining the amendment would give the U.S. some negotiating power to push for the rest of the Kigali holdouts to ratify and to accelerate the move away from HFCs, much as the Inflation Reduction Act will likely help with global climate talks coming up in Egypt in November.

There have been good signs that ratification might be on the way. In May of this year, the Senate Foreign Relations Committee advanced the amendment by a voice vote without any Republican opposition. And last week, Carper told reporters that the full Senate would vote on Kigali after its August recess, an announcement that — while it did get climate activists excited for this newfound climate momentum — appears to have been premature.


A Senate aide told Grid that no vote is actually scheduled. As is clear from its move out of committee though, the amendment does enjoy at least some bipartisan support. In fact, in 2018 a group of Republican senators sent President Donald Trump a letter urging him to send the Kigali Amendment to the Senate for its consent, ignoring the climate angle but noting that ratification would create 33,000 American manufacturing jobs and increase exports by $4.8 billion while maintaining an industry lead over China. Trump did not take their advice; President Joe Biden sent it to the Senate in November 2021.

The business community is behind Kigali as well. Stephen Yurek, president and CEO of the Air-Conditioning, Heating, & Refrigeration Institute, has said the industry welcomes the predictability the amendment would bring and it would allow the U.S. to continue being a global leader in relevant technologies. “Our industry is committed to the ratification of this amendment and for providing the global leadership by the U.S. industry in meeting and exceeding the commitments made under it, just like we did with the original Montreal Protocol,” he said.

The Senate just took its biggest climate action ever with passage of the Inflation Reduction Act, but there’s another major climate win lurking on its to-do list.

Whether the Senate’s climate momentum continues and the amendment is ratified remains to be seen. “[The U.S. was} at the forefront of efforts to get HFC phasedown under the Montreal Protocol in the Obama administration. They were one of the founder proponents of the proposals,” Peters said. “U.S. formally ratifying would be very significant.”

[Editor’s note: An earlier version of this article ran on Grid here.]

Thanks to Alicia Benjamin for copy editing this article.

  • Dave Levitan
    Dave Levitan

    Climate Reporter

    Dave Levitan is a climate reporter for Grid where he focuses on interconnected stories about climate and science, and politics shaping action around both.