A REPORT commissioned by the coal seam gas industry into its own greenhouse gas emissions, and held as commercial-in-confidence for months, shows that Australian gas exported to China is likely to be little better for the environment than coal.
The industry has been running an advertising campaign claiming that coal seam gas is ''up to 70 per cent cleaner than coal''. But the report, by consulting firm WorleyParsons, compared black coal and coal seam gas exports from Australia to China and showed that only best case scenarios come close to the promised major greenhouse gas savings.
Gas would release less CO2 when burned in a Chinese power plant, but most of the difference would be eaten up by the extra emissions from extracting and processing the gas in Australia.
While the emissions from processing coal made up only 2.7 per cent of its total greenhouse gas output, processing made up 22 per cent of the total emissions from coal seam gas.
The industry is already under fire from the independent MPs Tony Windsor and Rob Oakeshott, who have tied their support for the federal government's resources tax legislation to an investigation into the benefits of coal seam gas.
The report calculated a range of scenarios, the majority of which showed gas would perform slightly better than coal. It excluded the possibility of major or ongoing serious methane leaks from coal seam gas wells, and relied on data from the American Petroleum Institute.
The Australian Petroleum Production and Exploration Association, which commissioned the study, has previously said studies questioning the greenhouse performance of coal seam gas were ''trumped-up rubbish''.
An independent study of the life-cycle emissions of coal seam gas has just been completed by Beyond Zero Emissions. The group's executive director, Matthew Wright, was critical of the industry's report.
''It shows that they are actually relying on out-of-date data from the American Petroleum Institute to come up with their emissions scenarios,'' Mr Wright said.
''This shows that the industry's claims have been grossly misleading. It is making comparisons to Chinese power plants, but China is not building inefficient power plants like that - they have binding energy efficiency targets for their provincial governments.''
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