However, a trend continues since the CEDEX started, with consumption of petroleum fuels and associated emissions continuing to grow steadily.
According to Hugh Saddler, principal consultant energy strategies, pitt&sherry, “the continued fall in electricity generation emissions more than offset strong growth in emissions from petroleum fuels, while emissions from non-electricity natural gas used were almost unchanged”
Statistics on road transport activity and fuel consumption, published by the Bureau of Infrastructure, Transport and Regional Economics, indicated that, over the six years from 2005-06 to 2011-12, diesel fuel consumption by articulated trucks increased by 26%, which is almost exactly equal to the growth in total bulk diesel sales. The data also suggested that heavy trucks and buses accounted for over one-third of total diesel consumption.
“Clearly, then, heavy road freight traffic is a major contributor to growth in diesel consumption. Overall, consumption of bulk diesel increased by 31% over the six years and the total increase in emissions was 10.1Mt CO2-e,” said Saddler.
Consumption of aviation fuels grew even more quickly, up 40% over the same period. However, total volumes were less than diesel volumes, so the corresponding increase in emissions, 5.6 Mt CO2-e, was somewhat less. Transport statistics showed that this growth in consumption was consistent with the growth in total passenger kilometres travelled by air.
Trucks, heavy vehicles driving emissions up
Consumption and associated emissions from both petrol and automotive LPG have fallen slightly, while consumption of diesel has grown strongly. Nevertheless, use of petrol still contributes 68% of emissions in this category.
Consequently, while emissions from diesel have increased by no less than 65%, total emissions have increased by only 4% and total emissions by 1.1 Mt CO2-e over the six years to June 2012.
Although the shift to diesel engine cars is a well-recognised trend, the road transport statistics suggest that light commercial vehicles have contributed about two-thirds of the total increase in diesel consumption and cars only about one-third. This reflects the fact that light commercial travel (measured as vehicle kilometres travelled) is growing significantly faster than car travel.
In fact, the transport statistics suggest that car transport fuel consumption has increased by less than 1% over the six-year period, while fuel consumption by light commercial vehicles (4x4, trucks, vans and buses) has increased by over 14%.
“In volume and emission terms, the absolute growth in light commercial transport is four times greater than the absolute growth in car transport. These trends present major challenges for both transport and emissions policy,” Saddler said.
“Consumption of petroleum fuels, mainly for transport is currently the largest driver of increased emissions in Australia. Australia’s Greenhouse policy needs to increase its focus on transport emissions,” concluded Saddler.