“Gas could be just as dirty as coal, study reveals”
COAL seam gas, widely touted as a greener fuel than coal, could have just as deep a carbon footprint unless world-class standards are used when extracting the gas from the ground, an expert report has found.
A study into the life-cycle greenhouse emissions of Australia’s energy sources by consultancy WorleyParsons found conventional gas from large offshore wells typically produced 38 per cent less greenhouse emissions than black coal, largely because it burnt more cleanly.
But the equation could shift dramatically for the fledgling coal seam gas industry – the subject of a fierce political battle in NSW and Queensland – if meticulous standards were not followed when the gas was extracted from the ground.
So-called ”fugitive emissions”, particularly of methane, which is a much more powerful greenhouse gas than carbon dioxide, can tip the balance and make coal seam gas as dirty a fuel source as black coal burnt in ageing power plants, the report says.
”If methane leakage approaches the elevated levels recently reported in some US gas fields … the [greenhouse gas] intensity of CSG … generation is on a par with sub-critical coal-fired generation,” the report states.
The lead author, Paul Hardisty, said in a statement: ”The implications for regulators and the emerging Australian CSG industry are that best practice applied to design, construction and operation of projects can significantly reduce emissions, lower financial liabilities under the carbon tax, and help make CSG a less GHG-intensive fuel option.”
The report comes ahead of the introduction of the carbon tax on July 1, amid a battle between green groups and the energy sector over how to shift Australia to a cleaner energy mix. Many environmentalists argue that gas is little cleaner than coal and urge governments to encourage a quicker switch to renewables such as solar and wind energy.
But many in the energy sector argue a swift transition to renewables is unrealistic and gas – including coal seam gas – is needed as a stepping stone.