Ways to save – Road transport
Adopt fuel efficient corporate and driver practices
Opportunities targeting driver skills, attitudes to driving practices, planning techniques and procedures can provide significant savings when suitably applied to fleet management strategies.
Improve driver practices
Improved driver skills can account for an increase of up to 30% in fuel economy. It therefore makes sense for operators to identify, retain and develop the most efficient drivers in the fleet. Human resource practices should reflect the company’s focus on fuel efficiency by recruiting skilled drivers and investing in driver training and incentives to encourage drivers to drive smoothly, anticipate traffic, minimise idling, plan routes and other eco-driving practices. Computer-based programs and simulators are available to assist in such training. Simple awareness-raising material such as newsletters and leaflets are also effective.
Undertake fuel data collection, analysis and performance management
When it comes to vehicle energy use, a lot of operators in the road transport industry tend to keep aggregate fuel records across the entire fleet rather than focusing on smaller groups or individual vehicles. Aggregated information makes a detailed analysis of opportunities more difficult.
Data analyses of individual vehicles, drivers and routes provide the basis for improving fuel efficiency performance. Many of the emerging engine and drivetrain opportunities are largely dependent on the duty cycle of the vehicle, and the duty cycle varies across the fleet. High-level aggregated data does not allow operators to determine which vehicles and drivers are performing well and which are performing poorly.
Energy-usage data should therefore be captured, at a minimum, for different segments of the fleet. Ideally, it should be on a vehicle-by-vehicle basis. Monitoring of data from fuel cards, vehicle management systems, GPS and telematics can be progressively improved to enable this to be done cost effectively.
For more information
(PDF 4.3 MB)
Department of the Environment and Energy (2011)
The Energy Efficiency Opportunities document ‘Measurement and Opportunity Evaluation in the Transport Sector’ provided detailed guidance to transport operators that were involved in the EEO program on how to measure and analyse data to identify and evaluate fuel efficiency opportunities.
(PDF 3.6 MB)
UK Department for Transport (2011)
This comprehensive guide shows the transport professional how to choose the right telematics system for their operation in a step-by-step manner. It offers detailed information on different types of systems and system suppliers, as well as practical advice on how to implement a system using 11 real world case studies.
Undertake route planning and load consolidation
Route planning can be an important strategy to reduce distance travelled, improve fleet utilisation and avoid traffic congestion.
Look for opportunities to deliver different kinds of products to multiple customers by combining the load into a single vehicle and trip. Consulting directly with drivers or freight customers can highlight opportunities to change delivery schedules to avoid peak traffic periods.
Opportunities may also exist to consolidate loads from multiple smaller vehicles into larger vehicles (e.g. semi-trailer to B-double) or to load in such a way as to maximise carrying capacity, including the use of double-stacked trailers where possible. Longer combination vehicles (LCVs) with multiple or longer trailers are around 10–20% more fuel efficient on a tonne per kilometre basis, than typical combination trucks. Application can be limited, as LCVs are only permitted on certain routes.
Computer-based vehicle booking can help to reduce the size of a fleet and to minimise total distance driven. Review of GPS data on completed tasks may also reveal inefficient routing, while determining the most efficient vehicles to use and opportunities to reduce trips and distance driven. Some GPS devices can also receive real-time data on traffic congestion and accidents (currently available in Sydney, Melbourne, Perth, Brisbane and Canberra).
- US Environmental Protection Agency Longer Combination Vehicles: A Glance at Clean Freight Strategies US EPA (Opens in a new window) 93 KB ↩
Opportunities may exist to work with major clients to reduce and optimise the overall level of packaging used. This allows for more efficient loading of vehicles, thereby improving the vehicle’s productivity in terms of fuel or emissions per unit of payload.
In some cases, improvements are easily captured with a small amount of cooperation between transport operator and freight customer. In other cases, a great deal of collaboration is required along the entire supply chain, and trials may be required to ensure service quality is maintained.
Implement better procurement practices
The principles of fit-for-purpose procurement can be implemented whenever vehicles are due for replacement, refurbishment or upgrade. Poorly-specified trucks waste fuel and cost more to maintain and operate than necessary. By ensuring that trucks are fit-for-purpose, newly purchased vehicles can achieve the lowest consumption per unit of power. Whole-of-life costs and maintenance costs are also reduced when engines and drivetrains are not overworked. The principles apply equally to truck bodies and trailers as they do to the base vehicle.
New truck designs are enabling fuel efficiency improvements of up to 50%. These large efficiency gains are being made possible by significant improvements in aerodynamic design, hybrid engine innovations and advances in light-weighting material.
Reviewing a company’s policy on the length of time trucks are kept in operation before replacement is worth considering. A longer retention time can help to justify an investment in vehicles that are more efficient, providing maintenance programs are adequate. Conversely, if analysis indicates some vehicles are much less efficient than those currently available on the market, accelerated replacement may be justified.
For more information
Department of Infrastructure and Regional Development (2014)
The Truck Buyers Guide is a joint Victorian, NSW and Australian Government initiative to promote the uptake of low-emission small trucks.
Implement preventative maintenance
Maintenance programs can reduce average fuel consumption rates by ensuring that vehicles are tuned for optimal performance. The potential for fuel savings and emissions abatement may be as high as 5%.
The use of low-viscosity lubricants in maintenance programs can reduce friction and energy losses. The combined effect of low-viscosity synthetic engine oils and drivetrain lubricants can improve fuel economy by at least 3%, saving nearly 2,200 litres of fuel per year for a typical combination truck.
There are regular formal maintenance checks that drivers should carry out, such as monitoring tyre pressures. Truck tyres inflated 10 psi below recommended air pressure levels can lower truck fuel efficiency by 0.5% to 1% by increasing rolling resistance. Under-inflated tyres can also increase tyre wear, create irregular tread wear and reduce casing durability. Regular monitoring by drivers can generate instant savings. Automated monitoring and tyre-inflation systems are also available.
Review highway average speed policy
Reducing speed can yield significant fuel savings. Aerodynamic drag increases exponentially and becomes the major contributor to power requirements at speeds faster than 80 km/h. Reducing highway speed from 100 to 90 km/h can reduce fuel use by nearly 10%, and can lower tyre wear and crash risk.
In developing a recommended highway speed, companies need to take into account the costs and logistics of labour, rest breaks, and delivery schedules which may be affected by reduced speeds.
Invest in fuel efficiency improvements
Better fuel efficiency can be achieved by improving aerodynamics and tyre performance, and light-weighting to reduce rolling resistance. Parts and systems can be replaced or modified on existing trucks to yield a fuel efficiency benefit in these areas. Most fuel efficiency improvements apply to conventional vehicles and affect the engine itself or the vehicle drivetrain and chassis.
Replace ancillary equipment with more efficient models
Some vehicle accessories such as lighting, air-conditioning and power steering can be optimised for efficiency, or alternatively powered.
For example, LED lights use 80% to 90% less electricity than standard lamps, saving electricity that would otherwise need to be generated by the engine-driven alternator. Kenworth Australia are replacing incandescent globes in new trucks with high output, low power, high intensity discharge (HID) exterior and LED interior lights over the coming years.
Better designed vehicle air conditioners can reduce fuel consumption significantly, while providing an equivalent level of cooling. More efficient alternators and power steering pumps could also improve fuel economy by a further 1%.
Replacing accessories with more energy efficient models can be expensive, so it is important to estimate the current fuel usage associated with the equipment and to quantify the costs for upgrading these systems to determine the investment case.
Optimise gear settings
Optimising gear settings results in a more efficient use of the engine’s torque more of the time by maintaining optimum engine speeds for the conditions.
In 2003, Cootes Transport Group Pty Ltd undertook a review comparing trip times/truck engine load and fuel usage. They trialled a reduction in engine RPM by operating a taller set of gears. The net effect was a significant reduction in fuel burn. All new units introduced operate with optimum differential gears. Estimated capital cost was $0, with annual savings of 7,720 GJ per annum or $280,00 per annum.
Automated manual transmission (AMT) systems can also offer reductions in fuel consumption and GHG emissions by automating a conventional manual transmission to optimise gear shifting during driving. An AMT takes a three-pedal manual gearbox and converts it to a two-pedal version by taking automatic control of the clutch function. The duty cycle of the vehicle should be considered, to ensure the benefits suit the application. AMTs are more suited to stop-start, high gear-shifting drive cycles.
In the heavy-duty segment, the main manufacturers all offer AMT systems. New versions of these gearboxes are bringing advanced features and integrated functionality with the truck’s other electronic systems. Renault also offers automated gearboxes in light commercial vehicles.
Consider tyre selection
Innovations in complex rubber compounds, casing construction and tread design, have led to the development of modern low rolling resistance tyres that can increase truck fuel economy.
A number of real-world trials indicate a likely range of fuel savings of 4% to 13% for heavy vehicles. By using low rolling resistance tyres, a combination long-haul truck could save over 2200 litres of fuel per year.
Traditional dual tyres can often be replaced with single wide tyres. This technology can be applied to all tractor and trailer tyre positions except the steering tyres. Fuel savings are achieved by lowering the weight and rolling resistance of the tyres and wheels, thereby reducing load on the engine. SAE International tests indicated a potential saving in fuel of 12% for highway applications and 10% for suburban travel. The US Environment Protection Agency (EPA) SmartWay program suggests a fuel saving of 4%.
When evaluating these technologies prior to adoption, issues such as maintenance cycles and life span should be considered.
Capping trailer tyres twice is another strategy which could be used to delay the need to purchase new tyres. Recapped tyres achieve similar mileage to new tyres (300,000 km) saving on both cost and the embodied energy used in tyres.
For implementation considerations and examples, see:
Implement aerodynamic modifications
At high speeds, aerodynamic drag can be the largest energy drain on a heavy vehicle. Fuel efficiencies can be achieved through better aerodynamic performance.
Reducing the space between the truck and trailer air gap will reduce aerodynamic drag between the truck cabin and trailer.
Trailer modifications, including smooth-side van trailers or side skirtings can reduce aerodynamic drag. Contrast this to drop decks with irregular shaped loads, stock crates and car carriers which can induce 10% to 30% more aerodynamic drag.
A range of truck modifications are also worth exploring including roof deflectors, chassis fairings, under-hood air-cleaners and truck vision systems that replace mirrors. Modifying or even removing accessories, such as air scoops, window deflectors, sunscreens and bull bars can also reduce air resistance.
The initial expense of installing aerodynamic features can be quickly recovered through fuel savings. For instance, an aerodynamic long-haul truck can achieve fuel savings of over 7,200 litres per year.
Reduce vehicle mass and mass carried
Every 10% decrease in truck weight can reduce fuel use by 5% to 10%.
Commercially available trucks that incorporate lighter materials into their design can be 4% lighter than the loaded weight of an average truck. This can save 900 litres per annum.
Additionally, there may be several ways to reduce vehicle mass such as:
- lightweight trailers
- alloy wheels and super-single tyres
- examining fuel quantity carried
- light stillage pallets.
Use alternative drivetrain engine technologies
Energy loss from engines can account for up to 70% of fuel consumed, in the form of waste heat that passes through the exhaust and the cooling systems. Alternative drivetrain engine technologies can reduce these losses and significantly improve overall energy efficiency.
Fully electric powered small to light trucking vehicles with aerodynamic body design are commercially available. These electric plug-in vehicles can be charged from any electric socket overnight, and are well suited for companies operating commercial vans and light trucks in urban areas.
Overall energy running costs can be reduced by up to 80% but need to be considered against the extra upfront costs of an electric battery drivetrain. TNT Express in the UK was the first company to operate these fully electric trucks. In Australia the technology has also been trialled in public transport bus fleets.
Hybrid electric drivetrains
Hybrid electric vehicles can deliver a significant fuel saving when matched carefully to the right application. They are best suited to urban freight applications with frequent stop-start conditions, which maximise the benefit of regenerative braking. TNT Express Australia launched the first fleet of diesel-electric hybrid trucks in Australia as replacements for conventionally powered vehicles in 2008.
Fuel efficiency improvements of up to 25% have been realised, however, potential benefits of hybrid vehicles are highly dependent on the duty cycle of the vehicle. They are not considered suitable for regional linehaul applications, for example, due to extended periods without braking. Factors such as battery life should also be considered.
Mechanical hybrid-electric drivetrains
In a mechanical hybrid system, hydraulic accumulators (rather than the batteries typical of electrical hybrids) are used to store energy. Like hybrid electrics, the most obvious applications involve frequent stop-start driving in urban areas.
Fuel and emissions reduction from implemented mechanical hybrid systems in light commercial vehicles saves 35% to 50% in fuel. While there is anecdotal evidence from trials in Australia, there are currently no commercialised options for mechanical hybrid systems. Eaton and Bosch-Rexroth systems are claimed to be near production-ready.
Capital costs have been cited as being approximately 15% higher than for a conventional vehicle with a payback period of three to four years. Maintenance and service requirements also need to be taken into consideration when evaluating whole-of-life costs.
The future is likely to see further developments in aerodynamic performance, light-weighting of materials, more fuel efficient tyres, the use of solar panels and cost-effective second-generation biofuels.
- Aerodynamic performance – Ongoing research in wind tunnel modelling of different road transport vehicle design will, over time, lead to further improvements and refinements in aerodynamic performance.
- Lightweighting – Significant research and development is occurring globally to increase the applicability of lightweight metals and composite plastics to road transport vehicles.
- Solar panels – Trucks have significant surface area that could be used for solar panels in future trucking designs.
- Second-generation biofuels – Globally, there is significant research being focused on how to develop cost-effective second-generation bio-fuels. One promising biofuel is cellulosic ethanol from agricultural waste. Iogen, a Canadian catalyst company, say they have developed the technology to make cellulosic ethanol using advanced catalysts which enable a 90% reduction in greenhouse gas emissions compared to refining oil to produce petrol. In addition, the production of second-generation biofuels from agricultural waste uses less water, land and agricultural fertiliser than the production of first-generation biofuels.
- US Environmental Protection Agency (undated) Weight Reduction A Glance at Clean Freight Strategies EPA, USA (Opens in a new window) 142 KB ↩
- Truck World (2009) Look into the future with Kenworth’s ‘Innovation Truck’ Truck World, Australia ↩
- Elliston B and Dennis M (2009) Feasibility of Solar-Assisted Refrigerated Transport in Australia ANU, Canberra (Opens in a new window) 96 KB ↩
- International Energy Agency (2010) Sustainable Production of Second Generation Biofuels IEA, Paris ↩
- Iogen Corporation (2009) ‘Lowers GHGs, increases energy security, helps build rural economies’ Iogen, Canada ↩
- International Energy Agency (2010) Sustainable Production of Second Generation Biofuels IEA, Paris