This is an op-ed piece I submitted to the Newcastle Herald on 1 December (not yet published as at date of this posting).
Gas is often portrayed as a clean energy source that could play an important role in a transition from dirty fuels such as coal and oil to a renewable energy economy.
This portrayal is now being seriously questioned.
The clean energy claim is primarily based on the fact that natural and coal seam gas (which is mostly methane) produces much less carbon dioxide than coal or oil when burned for fuel.
Origin Energy – Australia’s largest natural gas producer – states in its 2010 Sustainable Energy Report that its gas-fired Darling Downs Power Station in Victoria emits less than half the greenhouse gases of a typical coal-fired power station with the same capacity.
The NSW Department of Industry and Investment website states that “changing from electricity to gas for applications such as water heating, space heating and cooking could reduce greenhouse gas emissions by a factor of four.”
Locally, this claim was repeated verbatim in a recent media release from the Hunter Business Chamber on the eve of a visit to Newcastle by Advent Energy CEO, David Breeze, to promote his company’s exploratory gas drilling 55km off Newcastle’s coast.
Given the massive expansion of the gas industry now hitting the Hunter Valley, such claims deserve closer inspection.
Like coal and oil, natural and coal seam gas is a non-renewable fossil fuel. Methane, which can leak in the extraction and transport of gas, is itself a much more potent greenhouse gas than carbon dioxide. The amount of carbon dioxide currently produced by the burning of natural and coal seam gas is already a significant contributor to total greenhouse gas emissions, and this is expected to rise considerably over the next few decades.
In a recently published conclusion to a full carbon footprint assessment of the greenhouse impact of gas extracted from shale formations in the United States, Robert Howarth, Professor of Ecology and Environmental Biology at Cornell University, urges “caution in viewing natural gas as a good fuel choice for the future”.
Professor Howarth says that “using the best available science, we conclude that natural gas is no better than coal and may in fact be worse than coal in terms of its greenhouse gas footprint when evaluated over the time course of the next several decades.”
The “clean fuel” claim for gas is also linked to the fact that it does not produce the range of chemicals and particulates associated with burning coal or oil.
However, a full production-cycle analysis reveals an environmentally darker side to gas, dramatically portrayed in the film Gasland, a nominee for this year’s documentary Oscar.
Modern gas extraction uses the controversial technique of “fracking”, involving high pressure hydraulic fracturing of the geological substrata (usually either coal or rock seams) that contain the gas.
Fracking uses large quantities of water and a chemical cocktail. The technique has raised a range of concerns about ground and water contamination, air pollution, subsidence, and the handling of waste. Off-shore operations present a slightly different set of concerns, mostly related to the impact on the marine environment.
The current surge in the development of the gas industry occurred earlier in the United States than here. This week, the New York State Assembly voted for a moratorium on further gas exploration to allow safety and environmental concerns about fracking to be properly investigated.
Communities and environmentalists in the Hunter are calling for the same approach here, before the region is locked in to yet another industry with dubious environmental credentials.
