Sunday 21 June 2009

Ecologists’ own goal: ozone saver is global warmer

The Sunday Times
June 21, 2009
Jonathan Leake, Environment Editor

THE green movement’s greatest triumph – the abolition of ozone-destroying CFC gases in the 1980s – may become its biggest embarrassment because of research showing that their replacements are sharply accelerating global warming.
CFC, or chlorofluorocarbon, gases were widely deployed in air-conditioning and refrigeration units before they were found to destroy the ozone layer and banned under the 1987 Montreal protocol.
They were replaced by HFCs – hydrofluorocarbons – gases that have far less effect on ozone but have since been revealed as extremely powerful greenhouse gases.
A ton of HFC23 used in refrigeration has the same global warming potential as 14,800 . tons of CO2 A ton of HFC-134a, widely used in vehicle air-conditioning units, is equivalent to 1,430 tons of CO2. The problem has been increased by the rising demand for refrigeration and air-conditioning because of economic expansion and population growth in Asia.

A study out this week will warn that, by 2050, HFCs could account for up to 19% of global warming. “By 2050, the contribution of HFCs to global warming will be more than that of current global CO2 emissions from houses and office buildings,” said Guus Velders of the Netherlands Environmental Assessment Agency, who did the research.
“The contribution of HFCs to global warming is currently small, but can increase to between 9% and 19% of the total contribution by 2050.” CO2 He found that by 2050 the demand for HFCs was likely to have increased by 800% compared with today’s figures.
A separate study by the Environmental Investigation Agency (EIA), a campaign group, found that the biggest source of HFC emissions entering the atmosphere was air-conditioning in vehicles. Large amounts are also released in the manufacture of insulating foam used to make buildings more energy efficient.
Commercial refrigeration, including shop, restaurant and hotel chiller cabinets, are another big source.
The problem with air-conditioning and refrigeration units is that they leak the HFC cool-ants into the air, with about 30% lost each year. This means that HFC production has to rise to keep pace with new units and losses from existing ones.
The EIA said: “Atmospheric concentrations of hydrofluorocarbons are rising at about 15% per year, faster than any of the other [main] greenhouse gases, even though there are viable alternatives available that do much less damage.”
In 2005, global production of HFCs was estimated at 280,000 tons, roughly equivalent to half a billion tons of CO2 governmental Panel on Climate Change predicts this will rise to the equivalent of 1.2 bil by 2015. lion tons of CO2 Tony Juniper, the former director of Friends of the Earth, who was involved in campaigning against CFCs in the 1980s and 1990s, said industry had long known about the global warming threat from HFCs.
“We did not know so much about HFCs back in the 1980s,” he said. “But the evidence about them has been around since the 1990s and that should have given policy makers and business time to replace them too.
“The Montreal treaty was still a triumph in avoiding an ecological catastrophe that would have followed the loss of the ozone layer. Now we need to use that experience to avoid the threat of destruction from global warming.”