Tracking Australia’s greenhouse gas emissions

Demand for electricity in the NEM may be falling, but electricity generation is still driving Australia's energy related emissions higher, with some help from petroleum fuels.

The following is the latest report on Australia's energy emissions from pitt&sherry.

Energy use is the largest driver of greenhouse gas emissions, mainly due to the burning of fossil fuels in electricity generation, transport and industry.

Energy combustion accounted for 61 per cent of total Australian CO2-e emissions from all sectors except land use change and forestry in 1990, and 69 per cent in 2009. Furthermore, the energy sector has contributed more than 90 per cent of the total increase in emissions since 1990 (Figure 7, near end of the article). Trends in emissions from energy consumption therefore provide an accurate indicator of the extent to which Australia is limiting its growth in greenhouse gas emissions.

Total emissions reported in the latest pitt&sherry Carbon Emissions Index (Cedex) for the year to December 2011 are 3.4 million tonnes higher than they were in the year ending June 2011, and 5 million tonnes higher than they were in the year to March 2011, the lowest point in the past five years. This is equivalent to an annual growth rate of about 2.0 per cent. Emissions remain about 7 million tonnes below the maximum reached in December 2008.

Electricity

The emissions intensity of NEM electricity continued the increase first observed in July, to 0.881 kg CO2-e/kWh. This is a direct consequence of a decrease in electricity sent out from hydro generators in Tasmania and the Snowy and offsetting increases in output from both black and brown coal generators.

However, total electricity sent out from NEM generators, i.e. the total demand for electricity supplied by NEM generators, continued to decrease and, on an annualised basis, is now nearly 6 TWh, or 2.9 per cent, below the peak reached in the year to September 2010.

Petroleum

As foreshadowed in the previous quarterly update, this report looks particularly at petroleum fuel emissions. Emissions from the use of petroleum fuels have grown by 13 million tonnes, equivalent to 12 per cent, over the past five years. Growth slowed and consumption even declined briefly during the first half of 2009, but is now growing very strongly. The three main groups of fuels (shown below) account for about 95 per cent of total emissions from petroleum fuels.

Retail sales of petrol, diesel and auto LPG are, for the most part, fuels used for private transport. NSW and Victoria account for about 60 per cent of total sales of this fuel category. More strikingly, these two states have accounted for 80 per cent or more for the growth in consumption recorded over the past year, suggesting a particularly high level of dependency on private transport (or at least vehicles for which the fuel is paid for privately).

By contrast, the big growth in consumption of bulk diesel and petrol has occurred in Queensland and WA. These two states now account for over 50 per cent of total consumption of bulk diesel and, over the past year, have contributed about 70 per cent of the growth in consumption. Without a doubt, the main driver of this growth has been use of diesel for mining (mainly) coal in Queensland and iron ore in WA. Interestingly, however, consumption has also been growing strongly in NSW, Victoria and SA, particularly during the first half of 2011. This may have been driven by increased crop production activity in agriculture, following the ending of the drought. Cultivation (ploughing) which typically takes place in autumn is the major use of fuel in agriculture.

Consumption of aviation fuels includes fuel used for both domestic and international air transport has grown steadily. The trend in fuel use to the end of 2010 closely tracks the increase in domestic passenger traffic, as reported by the Bureau of infrastructure, Transport and Regional Economics. During 2011 growth in domestic passenger movement slowed, but growth in international passenger traffic accelerated, increasing by 5 per cent on an annualised basis from November 2010 to November 2011.

The energy use covered by the Cedex accounts for about 80 per cent of Australia's total energy combustion emissions, and 54 per cent of total emissions (excluding land use change and forestry), as reported in the National Greenhouse Gas Inventory. The emissions not covered include those from use of natural gas in WA, which is growing quite fast with the expansion in production of LNG and other mineral commodity processing, and those from coal used to produce steel, which have fallen by several million tonnes per year in the last couple of years. The figure below illustrates the growth in energy sector emissions, with the lines at the right showing the period and emission sources covered in the Cedex.

Data sourced from Department of Climate Change and Energy Efficiency and Cedex.

Increases in energy combustion have caused more than 90 per cent of the increase in total emissions since 1990. Coal is the largest source of energy emissions, and accounts for most of the growth. Trends in energy emissions are a reliable indicator of Australia's ability to achieve Australia's emissions mitigation and hold the key to reducing Australia's emissions as a whole.

The full report can be found here.

Related Articles