China has begun to rein in production of hydrofluorocarbons (HFCs), highly potent greenhouse gasses that are widely used as chemical refrigerants in household appliances and automobiles, two years before it is required to under an international agreement.
The policy, announced by the Chinese government late last year, is a significant step in global efforts to address climate change. However, the news comes amid ongoing challenges to stop emissions of HFC-23, the most potent greenhouse gas among the HFCs and one whose emissions are now officially banned in China.
The world’s largest producer and exporter of HFCs, China froze new production capacity for five of the most widely used HFCs on Jan. 1. The new policy was announced in a circular issued by the country’s Ministry of Ecology and Environment on Dec. 28.
The production cap comes two years ahead of a mandatory freeze in production required by the Kigali Amendment to the Montreal Protocol, a climate agreement signed by more than 125 countries, which China joined on Sept. 15. Under the agreement, China is required to freeze production capacity for all HFCs in 2024 before slowly phasing-down production to just 20 percent of current levels by 2045.
The Kigali Amendment also required China to destroy or otherwise eliminate all HFC-23 emissions “to the extent practicable” by Sept. 15 of last year. Incinerators, many of which were first installed in China two decades ago through a United Nations climate program, can destroy more than 99 percent of HFC-23 emissions.
However, individual companies are responsible for annual operating and maintenance costs, and it’s unclear if plant owners in China continue to run the pollution control devices or if they simply vent HFC-23 into the atmosphere.
HFCs are climate “super-pollutants” used in air conditioning and refrigeration that, on a pound-for-pound basis, have hundreds to thousands of times greater warming potential than carbon dioxide. If left unchecked, global HFC emissions could add an additional half degree of warming to the atmosphere by the end of the century.
China’s new policy calling for production freezes covers just five of the 11 HFCs produced in the country. But those five targeted by the environment ministry account for more than 75 percent of total HFC production in China, according to Energy Foundation China, a nonprofit that funds projects addressing climate change.
“This sends a clear signal to the market and to industry that China is taking actions to start to freeze these HFCs and to promote the transition to low GWP (global warming potential) refrigerants,” Han Wei, industry program deputy director for Energy Foundation China, said.
China and other countries are placing increasing focus on reducing emissions of HFCs and other “non-CO2” greenhouse gases such as methane, nitrous oxide and perfluorocarbons to combat climate change.
Carbon dioxide is the primary driver of climate change based on the sheer volume of the gas that has been emitted, but these other gases are far worse for the climate in equal volumes to CO2. Reducing these more potent greenhouse gases is seen as a cost effective way to address climate change in the near term while also tackling carbon dioxide emissions.
The Chinese government’s current Five-Year Plan, adopted last March, stated for the first time that efforts should be made to control “other greenhouse gases such as methane, hydrofluorocarbons and perfluorocarbons.”
Chemical plants in China produce 70 percent of the world’s HFCs and roughly half of the country’s production is exported, Han said. China’s production dominance means efforts to curb HFCs in the country will have an outsized impact on global HFC production and emissions as the chemicals slowly leak from air conditioners and other appliances into the atmosphere.
Alex Hillbrand, an HFC specialist with the Natural Resources Defense Council, called China’s new policy a “leadership step” and one he hopes other countries will follow.
“There could still be growth, but any growth that we see post 2022 in China is going to be a lot smaller in China than it would have been,” said Hillbrand.
Tad Ferris, senior counsel for the Institute for Governance and Sustainable Development, an environmental advocacy group based in Washington, noted that not all HFCs were included in the freeze and those that were could still see expansions if chemical companies already had environmental assessments for new production approved by government agencies. Ferris also noted that the current circular is not yet part of an official government regulation, which would carry more weight.
“There is solid progress here,” Ferris said. “It’s good and it’s welcome, but it’s not unexpected.”
While China is ahead of schedule on five HFCs, the country may still be struggling to meet last September’s mandate to eliminate emissions of HFC-23, the most potent of the HFCs as a greenhouse gas.
HFC-23 is 14,600 times more effective at warming the atmosphere than carbon dioxide. The chemical is an unwanted byproduct from the production of hydrochlorofluorocarbon-22 (HCFC-22), a chemical used as a refrigerant and a component in Teflon and other products.
A study published in 2020 in the journal Nature Communications found global HFC-23 emissions were higher than ever in 2018, the most recent year for which data was available, despite government policies that should have all but eliminated emissions of the climate super-pollutant. The study suggested that China was the most likely source of a large portion of the emissions due to the country’s role as the leading producer of HCFC-22.
A 2021 investigation of chemical plants in China by Inside Climate News found annual emissions of HFC-23 from HCFC-22 plants that fell outside a recent government subsidy program to destroy HFC-23 could be as high as the yearly greenhouse gas emissions of 29 million automobiles if none of the pollutant from these plants is destroyed.
Hu Jianxin, a professor of environmental science and engineering at Peking University in Beijing, conducted a survey of all known HCFC-22 producers in the country last year, including on-site visits to several plants. The vast majority said they were voluntarily destroying or otherwise eliminating HFC-23 emissions prior to China’s entry into the Kigali Amendment. Independent air monitoring could provide outside verification. China currently lacks a robust air monitoring network for HFC-23.
Prior to China’s entry into the Kigali Amendment, Hu and researchers with the Foreign Environmental Cooperation Office (FECO) of China’s Ministry of Ecology and Environment conducted a comprehensive study funded by Energy Foundation China on how the country could ensure it was meeting HFC-23 emission reduction requirements under the Kigali Amendment. The August 31 report recommended establishing a monitoring, reporting, and verification system as well as supporting research and development efforts to recycle waste HFC-23 into valuable chemical feedstocks.
China plans to have a monitoring network for HFCs as well as ozone depleting substances in place later this year, Guo Xiaolin, a deputy director with FECO said during a November 19 workshop on HFC-23 hosted by Energy Foundation China and FECO.
The United States has not signed the Kigali Amendment, though ratification has bipartisan support and industry support and may be taken up soon in the Senate. Two plants produce HCFC-22 in the United States, one of which already abates its HFC-23 emissions. The other, a plant in Louisville, Kentucky owned by chemical company Chemours, destroys more than half of its HFC-23 emissions but vents the remainder. The climate impact of those remaining emissions are significant, equal to the annual greenhouse gas emissions of roughly 700,000 automobiles. An EPA regulation finalized last year will require Chemours to destroy 99.9 percent of its HFC-23 emissions starting in October.
Policing emissions from chemical plants in China, or elsewhere, can be costly and requires not only constant monitoring but also effective reporting and enforcement capabilities at the national and local level. China, for example, recently led a concerted and ultimately successful effort to find and shut down chemical plants that were illegally producing CFC-11, a potent greenhouse gas that also depletes atmospheric ozone. The government action came after scientists outside of China detected elevated concentrations of the banned pollutant coming from the country.
Rather than committing China to a potentially costly game of cat and mouse over HFC-23 emissions for years to come, Hu and other researchers in China have been working to find ways to recycle HFC-23.
Currently a small fraction of HFC-23 emissions are captured and used for etching in semiconductor manufacturing and in the pharmaceutical industry. Researchers at the Zhejiang Research Institute of [the] Chemical Industry have been working for more than a decade to turn waste HFC-23 into valuable HCFC-22 and recently completed a successful pilot scale test of the process.
Industrial scale conversion of HFC-23 into HCFC-22 could happen this year, Hu said.
“If they really save money, I think all the companies can install this technology,” Hu said. “I think this is a sustainable way to deal with [HFC-]23.”
Hu also cautions that HCFC-22 production may not be the only significant source of HFC-23 emissions. Recent studies suggest new chemical refrigerants that were developed as climate friendly alternatives to HFCs by U.S. chemical manufacturer Honeywell may partially break down into HFC-23 as they degrade. So far, the studies suggest HFC-23 emissions from degradation of other chemicals is relatively small. Other chemical manufacturing processes may also produce HFC-23 as an unwanted byproduct, Hu said.
As of 2018, the most recent year for which data is available, there was a tremendous gap between the amount of HFC-23 emissions that were reported from HCFC-22 production facilities and the larger amount that scientists were detecting in the atmosphere.
Avipsa Mahapatra, climate campaign lead with the Environmental Investigation Agency, a nonprofit environmental organization based in Washington, said the new research on other potential sources of HFC-23 emissions, including from other manufacturing processes, merits further investigation.
“A lot of these gases are new, and we don’t know what the production pathways look like,” Mahapatra said. “Each company and their government is therefore responsible to ensure that it’s not just the HCFC-[22] by-production that is being controlled, but it’s anything and everything related to HFC-23.”
Hu, of Peking University, said he considers HFC-23 a high priority because of its outsized climate impact.
“We will try to figure out this chemical and eliminate emissions as much as possible,” he said.
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