Geosequestration: No silver bullet

By Ben McNeil – posted Friday, 26 November 2004

The Howard Government’s strong and continuing support for fossil fuels, and especially coal, seems to be a pragmatic policy. After all, coal is cheap, reliable and Australia has plenty for its own energy needs and export sales for decades to come. The downside is that burning coal, particularly brown coal, is the most intensive producer of the main greenhouse gas, carbon dioxide, that fuels global warming. Australia’s chief scientist (Dr Robin Batterham), has recently argued for a 50-80 per cent reduction in our greenhouse gas emissions by 2050 which is considered necessary by the scientific community to avoid “dangerous” interference with our climate.

However, Australia’s energy demand is expected to soar by half over the next 15 years and the Australian Greenhouse Office estimates that our total emissions will actually rise by between 126 and 140 per cent by 2020, relative to 1990 levels. Given the recent ratification of the Kyoto Protocol without Australia, the Howard government will be under intense international pressure to address greenhouse gas emissions beyond Kyoto. It has therefore pinned considerable hope on the “silver bullet” technology it promotes in its energy policy, “Securing Australia’s Energy Future”, in the form of carbon geosequestration.

The idea is simple. You capture emissions from the smokestacks of power stations and other large stationary sources, separate out the carbon dioxide then pump it underground to seal it away in deep saline aquifers, depleted oil reservoirs and uneconomic coal seams. Since coal and natural gas generate the great majority of our electricity needs, the advantage of geosequestration is that we could foreseeably continue to use our abundant fossil-fuel reservoirs while burying most of the offending emissions – a seemingly win-win solution. So alluring is this prospect that the Government says it will commit $500 million over the next decade to help develop these technologies through private investment

Although the scheme certainly has long-term potential, closer scrutiny shows the emission reductions over the short-to-medium term to be very modest indeed. For example, based on the Government’s own estimates, existing generators are projected to cover 97 per cent of our electricity needs by 2010 and 75 per cent by 2020. Given that geosequestration is economically feasible only for new electricity generation plants, this means that only 3 per cent of our electricity needs can use this technology by 2010, and only 25 per cent by 2020. And since the electricity sector contributes only a third of our overall greenhouse gas emissions, geosequestration could only reduce the total by at best 1 per cent by 2010 and 8 per cent by the year 2020. So even if we take that path, rising energy demands mean that by 2020 Australia’s emissions will still be at least about 118 per cent of 1990 levels.

The Government will need to do much more to defuse the climate change issue. The first and most obvious option is to boost the proportion of electricity generated by renewable sources (wind, solar, hydro, biomass or geothermal) which are being heavily promoted in Japan and Europe. Economically and environmentally, it makes sense to become an international market leader in this expanding global market. Our Mandatory Renewable Electricity Target of 2 per cent falls well behind the target of 10 per cent by 2010 for other developed countries, such as the UK and Canada.

Substantial cuts in emissions are possible in the transport sector as well. We can’t capture exhaust fumes from moving motor vehicles, but hybrid petrol and electric vehicles are available and have been launched with great commercial success. Hybrids not only halve the amount of greenhouse gases coming from the tailpipe but also halve the amount of petrol going into the tank. Governments elsewhere, including the UK, Japan and Canada, have introduced tax credits – valued at up to A$3,500 per car – on these technologies as consumer incentives. Even the US Government has introduced a US$2,000 tax-deduction, but Australia has no such sweeteners. The Federal and State governments could lead the way in promoting hybrid cars, considering they lease about 100,000 new vehicles every year. Both greenhouse gases and taxpayer running costs will drop by up to half for each of these efficient cars, and demand for any oil imports will fall accordingly – a win-win scenario.

In the late 1990s, British Petroleum (BP) pledged to cut its emissions by 10 per cent by 2010 and has already achieved this goal, all the while setting record profits. If a fossil-fuel company can achieve an economically viable drop in emissions, surely the Australian government could aim to do the same. The government must look far more seriously at other practical and economical ways to cut emissions in the short term, beyond simply burying our wastes underground. There’s nothing necessarily wrong with the silver bullet, it’s just that a much more diverse array of bullets are needed.

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