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Concern at Emissions and Health Impacts of Coal

By Ian Lowe

The expansion of coal seam gas operations could eventually produce as much greenhouse gas as all the cars on the road in Australia.

Two new reports have put energy options firmly on the political agenda. The Australian government has released a technical discussion paper on the greenhouse gas emissions from coal seam gas, and the University of Illinois has published a report summarising the scientific evidence of health effects from coal-fired electricity. Both these documents show an urgent need for new thinking about energy supply.

The Australian government’s paper makes a clear distinction between conventional gas wells and the extraction of gas from coal seams. As Dr Samantha Hepburn of Deakin University observed, this distinction has been motivated by evidence from the USA “suggesting that coal seam gas mining which incorporates hydro-fracturing is likely to generate more emissions than conventional gas methods”.

The issue of fugitive emissions from gas production has been a consideration for decades, as extraction of natural gas inevitably releases quantities of methane, a more potent greenhouse gas than carbon dioxide. The expansion of coal seam gas operations has heightened concern. As Professor Alan Randall of the University of Sydney has said, the industry “could eventually produce as much greenhouse gas as all the cars on the road in Australia”.

Randall welcomed the proposal in the paper to move from “back-of-the-envelope methods” to direct measurement of emissions, following the approach taken 2 years ago by the US EPA. The new regulatory regime would require direct measurement from any production wells using “fracking” to release the gas.

While gas is a much cleaner fuel than coal and produces much less carbon dioxide per unit of delivered energy, the climate change calculations are complicated by the fact that burning coal releases particulates and aerosols that reduce the amount of sunlight reaching the earth, offsetting some of the warming potential.

But the University of Illinois report draws together the scientific evidence of health impacts of these emissions from coal-fired power stations. Using data in a paper published in The Lancet, the report estimates “the worldwide health toll from air pollution due to coal combustion is 210,000 deaths, almost 2 million serious illnesses and over 151 million minor illnesses per year, not including the effects of climate change”. The main causes are particulate matter and oxides of sulfur and nitrogen.

It should be noted that there is a considerable uncertainty about these figures. While the best estimate of deaths per terawatt-hour of electricity from brown coal is 33, the 95% confidence interval stretches from 8 to 130. But even at the lowest figures found overseas, black coal would cause about 2500 deaths per year in Australia and brown coal 1500. That certainly demands urgent attention.

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It is rare for there to be a public debate in Australia about technological innovation, so I have been fascinated by the discussion about the provision of the broadband network. There is a very clear difference between the government’s proposal for an optical fibre network and the Coalition’s alternative of “fibre to the node”: glass fibre to street cabinets and the existing copper network from there to households.

There is a huge difference in the capacity of the two systems, with the fibre network promising speeds of 100 Mb/s and straightforward upgrades to ten times that speed, whereas the copper wires would limit speeds to 25 Mb/s. The system of nodes would require more electronics to be provided and maintained, but the fibre network would demand much more labour (and therefore money) for initial construction.

The technical experts have sided strongly with the government’s argument that the extra bandwidth provided by fibre is needed. Rod Tucker, director of the Institute for a Broadband-Enabled Future, was quoted in the commercial press as saying that the Coalition’s alternative provided “5 per cent of the speed” for “two-thirds of the cost”, referring to the estimates by the opposing parties of their budgets of $20.4 billion and $37.4 billion, respectively.

Other experts were very critical of the basic idea of utilising the ageing copper wires, a proposal described by one as “faith-based network engineering”. With Australian data downloaded in the last quarter of 2012 three times the figure only 2 years earlier, there is a strong case for doing the job properly. But at least the alternatives are out for public debate.

Ian Lowe is Emeritus Professor of science, technology and society at Griffith University.