Lowering fuel consumption is top of the agenda for car hauliers, but regulations and operational requirements can sometimes get in the way. Barry Cross examines the latest approaches and technology for cutting the fuel bill.

In the face of high fuel costs and weak profit margins, the need to reduce fuel consumption is among the most pressing strategies for any vehicle logistics road carrier. Adding even a few kilometres to fuel efficiency can make the difference between turning a profit in a year, or not. A push to reduce carbon emissions and pollution should, in theory, make this efficiency mandatory as well as beneficial.

But on the winding road between legislation and industry requirements, not all trucks drive in the same direction. With governments varying in their focus – some legislating more to lower carbon emissions, others to reduce nitrous oxide (NOx) and sulphur emissions, and some promoting alternative fuels such as ethanol or bio-diesel – these different objectives can actually work against achieving the others. Adding weight and space for filters to eliminate particulates, for example, can increase fuel consumption. Alternative fuels or hybrids might work well for shorter distances, but payloads – the amount of cargo that can be carried relative to a truck’s size and fuel efficiency – often drop.

That is not to say that significant advances are not being made by both truck and trailer manufacturers in engine technology, equipment, the use of lighter materials and even improved driver techniques. But some providers, particularly in the US, are finding that the latest equipment isn’t always the most fuel efficient – and that retrofitting older trucks might even save more money in the long run.

One emission gain omits another
Patrick Riley, senior vice-president of United Road, one of the largest hauliers in North America, says new emission regulations introduced by the US Environmental Protection Agency (EPA) have only one focus: to reduce the output of particulate matter and NOx emissions. Penalties leave no room for non-compliance, but Riley worries that the regulations come at the expense of fuel efficiency.

“United Road takes its environmental responsibilities very seriously,” he pledges. “However, US EPA regulations focus on emissions only, but do nothing to encourage an engine OEM to produce a more fuel efficient engine and there is very little onus on an engine OEM to improve fuel economy, especially if their competitors aren’t striving for improvements either.”

The change of regulations, while well intended, has had some perverse effects on the market, Riley claims. Car transporters operated by United Road prior to the earlier 2002 EPA emission standard engines are approximately 15% more fuel efficient than today’s new trucks, Riley emphasises.

 He points out that based on a per-Americangallon (3.8 litres) price of $3.85 for diesel, today’s EPA compliant trucks consume 1,731 more gallons of diesel per year compared to older equipment, effectively costing $6,700 more to operate.

“Our industry also has had to pay approximately $10,000- $15,000 per truck in additional equipment costs to obtain these sub-standard results,” he says, stressing that this issue should be addressed at an industry and regulatory level. Riley adds that while it is true that truck manufacturers have looked at other improvements, notably introducing automatic transmissions, variable torque engines and hydraulic fan hubs, little else of major importance has been done.

“In contrast, trailer and headramp manufacturers today are building better equipment than ever before. Unfortunately, due to the 1,200lbs (544kg) of weight that has been added to the truck over the past few years as a result of the extra emission regulations – not to mention the increased dimensions of the tractor chassis to fit the larger cooling systems, diesel particulate filter (DPF) and exhaust fluid tanks (DEF) – the size of loads that we are able to haul has been dramatically reduced,” he says.

Riley points out that the US Department of Transportation continues to regulate the industry under the same weight, height and length restrictions as it did 20 years ago, which has resulted in a loss of loadable space, requiring more trucks to haul the same amount of vehicle cargo.

Riley is also adamant that manufacturers are not doing all that they can do to ensure their vehicles are suitably aerodynamic. “There may be some air deflectors that could be added by the headramp and trailer manufacturers here and there [to] improve aerodynamics, but to my knowledge nobody is taking the lead in this area,” he says.

Contradictions specific to the car haulier industry. Enclosed car carriers allow for better aerodynamics, for example, but lose efficiency in added weight and lower payloads. As Riley sums up: “Enclosed auto transporters are significantly more fuel efficient, but they are heavier and can’t load the same amount of cargo vehicles as an open auto transporter. The trade-off is less revenue and productivity, but better fuel economy – and that makes no economic sense.”

Riley believes there have been some improvements in the use of lightweight materials. An increased use of highstrength low-alloy steel over the years has proven to reduce weight by approximately 20%. That, along with improved design engineering and increased use of aluminium, has had a positive impact, but not enough to stay ahead of the US EPA regulation changes, he says.

Modifications could be made to tractor-trailer combinations hauling finished vehicles to help reduce overall operating costs, he believes. These require investment related to the reduction or elimination of truck engine idling as the driver is loading and unloading using his power take-off (PTO) to operate the hydraulic system or while he is sleeping (in sleeper berth trucks only). There are electric PTO systems, electric- or diesel-powered auxilliary power unit systems or auto-start systems used in loading and unloading, which reduce engine idling as the hydraulics are used.

Given the disadvantages of buying modern trucks, United Road has taken the unusual step of looking at rebuilding its older equipment and putting new headramps and trailers on them to create a more fuel-efficient truck.

“We are currently testing this now,” says Riley. “We believe that there is a return on investment to be had from this approach. If we can show that it works then perhaps it will motivate engine OEMs to design new engines with improved fuel efficiency before this practice cuts into their new truck sales numbers.”

A different approach in Europe
On the other side of the Atlantic, carriers aren’t necessarily saying the same thing. European standards differ to American ones in many ways, but the European focus is generally less focused on NOx emissions, for example, than in the US. With fuel costs higher, there is arguably more focus on lowering consumption.

While fuel efficiency has generally been poorer for the car haulier industry, there have been improvements in engine development, according to Frank Müller, director of quality and environmental management at Bremen, Germany-based BLG Automobile Logistics.

New technologies are also coming onto the market that should help improve fuel economy further still, says Müller. He points to a hybrid fuel approach, for example, whereby gas is combined with normal diesel to reduce both the operational cost and the carbon footprint.

“Instead of using 33 litres of diesel per 100km, the consumption will change to about 23 litres of diesel plus 11 litres of gas,” says Müller.

He also points to the development of low-rolling-resistance tyres, which can be fitted to both the tractor and trailer and will reduce fuel consumption.

As for trailers, Müller echoes Riley in noting that a fully enclosed car carrier has better aerodynamics but lower loading capacity, which undermines the overall economics of the operation.

“There isn’t a lot that can be done, since adding a bodyshell spoiler would negatively reduce capacity, which just leaves side bodyshells as the only viable option,” he says. “In some instances, it is possible to use fully covered trailers, but these are only usually deployed by logistics companies in niche markets for premium-price vehicles or to move secret models. In these cases, capacity isn’t the main concern and so manufacturers will accept higher transport costs.”

Similarly, the use of new materials to make lighter trailers doesn’t always result in better fuel economy, since less weight invariably leads to the incorporation of more hydraulic parts. At the end, the total weight remains more or less the same.

“In contrast, state-of-the-art telematics can help reduce operating cost and also actively make tractor-trailer units greener by reducing the overall carbon footprint,” says Müller.

However, unlike United Road in the US, Müller sees no benefit in reverting to older, upgraded equipment to achieve better returns.

better returns. “From the technical point of view, many models cannot even be updated, even if the cost of doing so were not an issue. In general, in my opinion, on the grounds of cost alone, it would be too expensive to take this approach,” he says.

Gains from driver training
Müller also points to driver training as an important way to lower fuel consumption.

lower fuel consumption. “BLG gives special training to each driver several times a year, depending on their personal performance,” he says. “This training does have to be repeated, due to the fact that most drivers won’t change bad habits after a single training session and therefore have to be checked again. Incentive schemes, of course, also help to keep them motivated.”

Commercial vehicle manufacturer Scania says it has a proven record of being able to generate average fuel savings for an operator of 10% by putting just one driver through its training course, although press manager Hans-Åke Danielsson stresses that car transporter drivers don’t require any specialist driving techniques per se.

Fellow Volkswagen Group truckmaker MAN makes similar claims for its driver training course, MAN ProfiDrive. Detlef Hug, head of media relations, confirms that fuel consumption in truck fleets can be reduced by an average of 10%.

There are other tricks, too, notes Hug. MAN’s powertrain manager functions, such as the acceleration limiter, can reduce fuel consumption on empty runs simply by limiting the vehicle’s maximum acceleration.

“As 50% of a car transporter’s journeys are normally empty runs, this function would help the driver and the operator to decrease fuel consumption. It also cuts wear on the brakes and tyres, which in turn will be reflected in lower consumption rates and lower costs for the operator,” he says.

Indeed, with MAN Telematics, vehicle deployment can be optimally planned, unnecessary empty runs or searching prevented and the performance of both vehicle and driver opened up for examination. In this way fuel costs can be cut, in some cases considerably, claims Hug.

Danielsson also stresses the importance of new IT technology in fuel economy. Scania’s new cruise control system uses GPS to determine a vehicle’s position and to predict the topography of the road ahead. The cruising speed is adjusted before entering an ascent or descent, helping the driver make the most of every drop of fuel.

"This system can deliver a fuel saving of up to 3% when driving on undulating stretches of road, compared to highway or motorway driving with normal cruise control” he says. “It is intuitive and adapts driving style to the topography in the same way as the most highly skilled truck drivers would do. The system also helps experienced drivers to save fuel when driving on new routes, in the dark or under adverse weather conditions.”

Based on a 40-tonne truck combination (tractor unit and semi-trailer) running 180,000km per year, a fuel saving of 3% would reduce fuel consumption by about 1,700 litres per year. This is equivalent to an annual reduction in fuel costs of almost €2,200 ($2,800) and a reduction in carbon dioxide emissions of over four tonnes.

Another IT innovation that should also help save fuel is Scania Driver Support, which is a new real-time support system that gives professional truck drivers hints and feedback to refine their driving style. Now standard on most Scania long-haulage vehicles, it is designed to maintain the skills obtained during driver training.

Alternative fuels or no alternative at all
SScania places great faith in the development of alternative fuel technologies. All of its engines are already capable of running 100% on biodiesel, of which rapeseed-based biodiesel is just one example. Also on offer are bio-gas or natural-gas fuelled engines, as well as others that use ethanol.

“Gas-fuelled engines operate in the 305-340 horsepower range, while ethanol-based equipment is in the 270-280hp power range,” says Danielsson.

Significantly, MAN has yet to go down the alternative fuel technology route, continuing to offer only diesel engines. Hug stresses that diesel will remain the most efficient type of propulsion in the medium term, particular for long-haul transport. “We believe other measures, such as heat recovery or hybridisation, provide better potential for improvements in efficiency in the short term,” he says.

Nevertheless, MAN is testing alternative fuels for use in commercial vehicles, but results to date have not been encouraging. “In our view, the disadvantages of these for long-haul truck transport, in terms of operating range, loss of installation space, loss of payload, supply infrastructure and costs are still so great that it currently does not make sense for customers to use them,” he says.

At the limit of fuel efficiency
Danielsson believes the industry can still make substantial improvements in fuel efficiency, stressing that there are improvements already in the pipeline.

“When it comes to reducing CO2 emissions and at the same time lowering fuel consumption, Scania’s objective is to halve CO2 emissions per tonne kilometre by 2020 compared to 2000,” he says.

There are four areas in which this will be achieved: logistics – implying better usage of trucks and improved infrastructure; driver training; vehicle technology, which isn’t just engine development but also aerodynamic improvements and weight reductions to carry more goods, as well as making more load space; and increased use of biofuel.

Hug concedes that it is increasingly difficult to cut fuel consumption by conventional measures alone. Completely new approaches, like the MAN Concept S – a highly aerodynamic truck with flared wheel arches and curved cab lines – can nevertheless help to achieve a significant reduction in fuel consumption.

The company has great faith in its EfficientLine range of commercial vehicles. “Because our solution cuts fuel consumption by up to three litres, every TGX EfficientLine vehicle that takes the place of a conventional long-haul truck can save up to 4,500 litres of diesel a year, which is the same as 12 tonnes of carbon emissions,” says Dr Frank Hiller, MAN marketing director, sales and services.

The company has also experimented with intelligent aerodynamics as a means of saving fuel, noting that drag is a primary cause of extra fuel consumption. As a result, the TGX EfficientLine comes without fittings such as sun visors or compressed-air horns, while the tractor is fitted with aerodynamic side panelling and a roof spoiler tailored to the needs of a car carrier.

“Driving at only 85km per hour instead of 89km per hour, we have found that rolling resistance is reduced by 10%. That saves an enormous amount of fuel, but without losing a noticeable amount of time in daily operations,” says Hug.

He adds that getting a decisive few per cent more in fuel efficiency is not obtained just by improving single components; it is the result of optimising the entire drive train.

Common-rail engines, low-loss drive train components and intelligent gear shifting strategies all have to be matched for optimal interaction, he explains. For example, MAN’s upgraded three-phase alternator is not only 4% more efficient, but also delivers more generator power. Similarly, the daytime driving lights used require only about a quarter of the power of halogen dipped beams. The proprietary air-pressure management system also decreases the power loss in the EfficientLine model to generate compressed air.

For the moment, at least, there does not appear to be one approach, on either side of the Atlantic, to reducing fuel from a technological or alternative fuel point of view. Battles between industry and regulators are likely to persist as well. The question of whether the industry is doing ‘enough’ cannot really be answered, but in the struggle to reduce costs and improve margins in today’s economic climate, it’s fair to say that nothing is ever enough.