As the debate over heavy vehicle fuels moves from fears of dwindling supply toward greenhouse gas concerns, diesel is emerging
As the debate over heavy vehicle fuels moves from fears of dwindling supply toward greenhouse gas concerns, diesel is emerging as the dark horse in the field.
“We shouldn’t discount diesel as a fuel that, for its sheer efficiency, is a much better option from the perspective of carbon dioxide emissions than many other fossil fuels,” says Scania National Manager Contracts and Technical Graeme Miller.
Diesel’s trump card is its efficiency – the bang an operator gets for his buck.
Diesel has more energy per unit than most other fossil fuels, and there is a direct correlation between the amount of fuel burnt and emissions of carbon dioxide, the better the fuel efficiency, the lower the emissions of carbon dioxide.
For the last two decades, exhaust emissions regulations have been focused on the pollutants that are not particularly damaging greenhouse gases – nasties like particulates and nitrogen oxides.
The emission controls in Australia referred to as Euro 1, Euro 3 and Euro 4 that were incorporated in Australian Design Rules did not impose limits on the emission of carbon dioxide.
As greenhouse concerns have come to the fore, the emphasis has quickly switched to ways of reducing carbon dioxide from trucks. Fuels like biodiesel and ethanol, which burn with fewer emissions of carbon dioxide, are contenders to replace diesel.
But there are few hopes that these fuels could ever be produced in the sorts of quantities needed to replace diesel.
Scania Head of Research and Development and member of the board of Scania Australia Hasse Johansson predicts diesel will continue to be the primary fuel for heavy road transport and gains in efficiency offer the best opportunities to reduce emissions of carbon dioxide.
Scania aims to reduce carbon dioxide emissions per tonne-kilometre by 50 per cent by 2020, which would be achieved by making continuous improvements in vehicles, allowing longer trailers that carry larger cargos and increasing the supply of carbon dioxide-neutral fuels.
But most of the improvements will be achieved using diesel engines.
“Diesel is by far the most efficient fuel of any available for road transport,” he says.
“Trucks are much more efficient than cars in terms of carbon dioxide emissions per tonne-kilometre. A fully loaded truck with a gross weight of 40 tonnes consumes about 0.3 litres per kilometre. Compare that with a car that weighs 1.5 tonnes and consumes 0.08 litres per kilometre. This never comes out in the public discourse.”
Between 1970 and 2000, Scania reduced carbon dioxide emissions per tonne-kilometre by 50 per cent.
“Our new target is a further 50 per cent reduction by 2020,” he says.