While Politicians Debate HFCs Phase-Down, Companies Innovate

When you turn on the AC, what’s cooling you off is heating up the planet.

As temperatures rise, so do air conditioner sales, and what makes most of these 4 billion-plus machines cool indoor environments worldwide are HFCs (hydrofluorocarbons), gases with global warming potentials thousands of times greater than CO2.

HFCs started out as environmentally preferable alternatives to ozone-depleting CFCs (chlorofluorocarbons) and HCFCs (hydrochlorofluorocarbons), now being phased out by the Montreal Protocol. Then scientists realized their true global warming potential. HFCs use is now increasing so rapidly that scientists warn that if not curtailed, greenhouse gas impacts of HFCs could undermine other efforts to curb global warming.

HFCs are so potent — atmospherically and politically — that the outcome of ongoing negotiations about their regulation could significantly affect both the rate of global warming and the course of international climate change legislation.

“Today, HFCs play a relatively small role in global warming, but the game will change if we address CO2 but do nothing about HFCs,” says David Fahey, research physicist with NOAA’s Earth System Research Laboratory and co-author of a study published in June by the Proceedings of the National Academy of Science that upended beliefs that the energy efficiency of HFCs would mitigate their inherent global warming potential.

Air conditioner sales have been growing by double-digit percentages throughout the Asia-Pacific region, where China recently surpassed the United States as the world’s largest market. The 2008-2009 economic downturn notwithstanding, sales have also increased steadily in Eastern Europe, Latin America, Africa and the Middle East. Refrigerator and air-conditioned car sales have also been climbing in these regions. HFCs currently contribute only about 2% of greenhouse gasses, but if left unchecked, by 2050 HFCs could account for 9-19% of greenhouse gas impacts, the researchers found.

“The run-up in HFC use,” observes Fahey, “is related to GDP growth.”

Chemical manufacturers are working on a new generation of fluorine-based refrigeration compounds with lower global warming potentials to replace HFCs, but the greenhouse gas impacts of HFCs have prompted a number of major corporations — including Coca-Cola and Unilever — to begin adopting technologies that avoid any fluorine gases.

“Looking at our overall climate impact, what surprised us was that our refrigeration equipment was the biggest contribution to our carbon inventory,” says Bryan Jacobs, director of energy and climate protection for Coca-Cola.

Wal-Mart made a similar discovery and has also begun to shift its commercial refrigeration to alternatives.

Billions of pounds of HFCs have been sold and emitted over the past decade. But the production figures typically reported by the consortium of the world’s largest fluorocarbon producing companies, AFEAS, and often used to calculate environmental impacts, do not include production in Asia outside of Japan, despite the fact that all major producers have initiated joint ventures or similar arrangements to produce HFCs in China.

Adding to the overall HFC impacts are thousands of tons of HFC-23 — an HFC not included in the PNAS study — that have also been emitted over the past decade. HFC-23 is not produced commercially but is a manufacturing by-product of HCFC-22, one of the most widely used HCFCs, and it has a global warming potential about 12,000 times greater than CO2. It’s been estimated that by 2015, HFC-23 emissions could reach the equivalent of 284 million metric tons of CO2 or 0.1 to 0.2 % of overall global warming impacts worldwide. Alone this may not be much, but given current greenhouse gas levels and their effects, policy-makers have begun to act.