There are significant opportunities across the transport sector to improve fuel efficiency, with a range of technologies and innovations such as reducing vehicle weight, alternative drivetrains, improved aerodynamics and alternative fuels.
Combining best practice and technological improvements can lead to as much as 30% savings in energy costs in each of the major commercial transport/freight sectors.
Opportunities to save
Improve the physical structure
Better fuel efficiency can be achieved by using technologies for reducing rolling and air resistance. Many technologies exist to improve aerodynamics and wheel/tyre performance. Lightweighting materials save energy by reducing rolling resistance. This also enables the use of fuel-efficient alternative drivetrains, as less power is needed for lighter vehicles.
Improve mechanical design
Energy loss from engines can account for up to 70% of fuel consumed, primarily in the form of waste heat through the exhaust and cooling systems. Alternative drivetrain engine technologies can reduce and recover some of these losses and significantly improve overall energy efficiency. Reducing energy losses from idling is also beneficial.
Electric powered and hybrid vehicles are becoming more widely used as performance improves and the cost of batteries falls.
Ongoing wind tunnel modelling of different transport vehicle design will lead to further improvements and refinements in aerodynamic performance.
Significant research and development is contributing globally to increase the applicability and strength of lightweight metals and plastics to further replace heavier metal parts in modern vehicles.
Second generation biofuels
Globally, there is significant research focused on the development of cost-effective second generation biofuels. Cellulosic ethanol has the potential to provide better energy balance, lower GHG emissions and requires less land use than starch-based biofuels. It can be produced by converting chemical compounds in agricultural wastes into sugars which are in turn converted into ethanol.
Another promising second-generation biofuel has properties similar to diesel.
Advanced biodiesel includes:
- hydro-treated vegetable oil (HVO)
- biomass-to-liquids (BtL) diesel produced by a two-stage process
The airline industry has recently demonstrated that jet biofuel can be successfully blended with kerosene to fuel long commercial flights, though production cost remains a barrier to greater use.
High hopes are held in the longer term for the use of algae as a biomass for the production of biofuels. It offers the possibility of a high yield — about 100,000L of oil per hectare compared to palm oil at about 5000L per hectare. It also does not require premium land, and so has far less environmental impact than palm oil harvesting.
At present, it is expensive to cultivate algae and extract oil. To be commercial, high-volume production of low-value biofuel will need to go together with high-value co-products.
Challenges include optimising strains of algae, minimising risks of contamination and achieving the necessary scale of production. Australia producers include:
- the South Australian Research and Development Institute, which is constructing a demonstration bioreactor and investigating the sustainability of production of biodiesel from microalgae
- Smorgon Fuels, which has moved to the commercialising phase of a process that converts algae to biodiesel using waste gas from power stations.