Consistently efficient on the go – operators enthuse over MAN TGX and TGS EfficientLine
- Efficient long-haul transport solutions in MAN's range of semi-trailer tractors provide more flexibility
- Consistent design saves up to three litres of diesel
- Training course on economical driving included
Semi-trailers setting their sharply angular lines against the wind. Sun visors and trucker horns creating turbulence in the airflow. Tyres rolling at low pressure with lots of flexing work to do. There are plenty of examples of how to throw money away when operating a semi-trailer tractor. They're often only small, inconspicuous things that go unnoticed in daily operation. But their contribution to the total operating costs adds up from day to day When one then also considers the increasing cost of diesel fuel, potential savings become ever more important.
MAN Truck & Bus has analysed the factors that form obstacles to achieving the goal of efficient transport. With its TGX EfficientLine tractor, MAN became the first commercial vehicle manufacturer to implement the known interrelationships of physics consistently when it presented the vehicle at the IAA 2010. In the six months since sales began, customers from all over Europe have ordered around 800 of MAN's EfficientLine tractors.
The specifically developed drive technology and a scope of equipment rigorously designed to save fuel demonstrate that today's long-haul transport has the potential to save up to three litres of diesel per hundred kilometres. The MAN EfficientLine shows: whoever strives to become more efficient in long-haul transport will have to design their vehicles with the main objective of reducing driving resistances. The reward for this effort is something to be seen. Given the high annual mileages of trucks in long-haul transport with an average of 150,000 kilometres, a saving of three litres of fuel over a four-year period of use means a saving for the operator of up to 18,000 litres. And the environment will be spared the impact of up to 47 tonnes of CO2.
Save with sophisticated aerodynamics
Because drag is the primary cause of fuel consumption in long-haul transport, the MAN EfficientLine only comes without fittings such as sun visors or compressed-air horns on its standard long-haul cabs, the XLX and XXL on the MAN TGX and the LX on the MAN TGS. This saves around 0.3 litres of diesel per 100 kilometres. At the same time, the aerodynamic side panelling and roof spoiler that belong on the tractor, optimally adjusted for the semi-trailer, reduce fuel consumption by approximately 0.4 litres.
The MAN EfficientLine stands for a further consequence of the laws of aerodynamics: driving at only 85 km/h instead of 89 km/h reduces rolling resistance by ten percent. That saves an enormous amount of fuel without losing a noticeable amount of time in day-to-day work. At the end of a nine-and-a-half hour trip, the vehicle will have covered a mere 38 kilometres less. This as opposed to a fuel saving of 19 litres! That's why the top speed of the MAN EfficientLine is electronically restricted to 85 km/h. With this measure alone, drivers in field tests were able to reduce consumption by 0.6 to 2.2 litres. Faced with rising fuel prices and finite, non-regenerative resources, acceptance nowadays is already at a high level.
Efficiency can be trained
When designing the EfficientLine, MAN consulted intensively with drivers, because their care and skills have a major influence on fuel consumption. The experience of the MAN ProfiDrive® driving instructors shows that drivers who have been trained to drive economically can save a significant amount of fuel, primarily thanks to a forward-thinking style of driving and optimum use of MAN's efficiency systems such as the adaptive cruise control system ACC or the MAN TipMatic®. This is why a practically oriented driving course from MAN ProfiDrive® is included in the price of the MAN EfficientLine package on most markets.
Optimised power train
As a result of this consistent focus of the MAN heavy-duty TGS and TGX ranges, the total costs of ownership per kilometre are very low. The decisive last few percent more in terms of efficiency cannot be obtained just by improving individual components: they are the result of MAN's development competence when it comes to optimising the entire power train.
Common-rail engines, low-loss power-train components and the intelligent gear-change strategy of the MAN TipMatic® are all matched to one another to form a perfectly coordinated unit. The MAN EfficientLine can be ordered with engines delivering 400, 440 and 480 hp, whose power is transmitted through direct-drive gearboxes. In combination with hypoid single axles this keeps friction losses in the power train at a minimum. Direct drive in top gear enables a saving in fuel consumption of around two percent relative to the overdrive version when the vehicle is operated mainly on motorways.
The optimised gear-change strategy of the MAN TipMatic® Fleet in the MAN EfficientLine changes to the most economical gear at exactly the right moment and provides maximum torque whenever it's needed. Also available for those who want it is the MAN TipMatic® Profi, which can be operated both manually as well as fully automatically. The average saving achievable in long-haul transport with the MAN TipMatic® is around 4.5 percent – that's an enormous potential saving.
The new Intarder generation
The MAN EfficientLine introduces a new, more efficient generation of Intarders. The around 25 percent lower friction losses when idling reduce fuel consumption by approximately 0.15 litres per 100 km. Faster response times improve safety because the braking effect is nearly instantaneous. Operating noise is also two to three decibels lower. The sustained-action braking system provides uninterrupted deceleration even during gear changes and is integrated into sustained-action braking management with automatic brake control. Transmission oil in vehicles equipped with the Intarder reaches operating temperature sooner, thus reducing wear and tear. The new Intarder generation is fitted with a long-life stainless-steel oil cooler.
More efficiency: less loss
The MAN EfficientLine is not at all miserly, saving money by starving itself of comfort and performance. Just the reverse, in fact: the customer gets a fully equipped truck with lots of extras, a truck whose speciality lies in its sophisticated technical features, which are available elsewhere only as options. What makes the MAN EfficientLine stand out from the masses is its package of efficient features:
the new three-phase alternator is four percent more efficient and at 120 A, simultaneously delivers more generator power. Its halogen daytime running lights need only a quarter the energy of a halogen dipped beam, thus saving energy that the generator doesn't even have to produce.
MAN's air-pressure management (APM) decreases the loss incurred by the EfficientLine when air is compressed. A multi-disc clutch deactivates the compressor completely when the cut-off pressure has been reached in the air tanks. Once compressed air is drawn from the tanks, the clutch engages and the air compressor again works up to cut-off pressure. In this way the operating time of the compressor in long-haul transport is reduced by up to 90 percent, thus saving half a litre of fuel per 100 km.
The rolling resistance of the tyres is decisive for economical operation: on a six-wheeler semi-trailer tractor, tyre pressure that is too low by a mere 2 bar will increase fuel consumption by 1.2 l/100 km. A long period at the incorrect pressure and damage to the tyres will result. In its tyre pressure management system TPM, MAN offers an electronic aid that will immediately detect and display any incorrect pressure in one or more tyres. The tyre pressure management system not only saves fuel, it also prevents over 90 percent of all tyre flats and avoids expensive vehicle downtimes. Optimised Energy tyres contribute further to reaching the best-possible rolling resistance values.
Lower unladen weight means less energy per transported tonne
The gross vehicle weights allowed on the road are restricted, so commercial vehicles with lower unladen weights can transport more cargo. This means more cargo on each journey, which in turn means that fewer journeys are necessary. Making fewer journeys also takes some of the strain off the transport network. Moreover, shipping the same amount of goods uses less energy and emits less CO2.
MAN employed lightweight construction throughout in its TGS and TGX series, thus enabling maximum payloads. The TGX EfficientLine is equipped with particularly light front- and rear-axle suspension, together saving around 80 kg: the re-engineered front-axle suspension with its single-leaf spring is not only light, it also improves the handling. Compressed-air tank, fuel tank and wheel rims of aluminium all contribute to keeping the vehicle's weight down.
All in all, consistently efficient on the go with MAN
With its presentation of the TGX EfficientLine at the IAA 2010, MAN demonstrated the potential of the two-axle semi-trailer tractor for saving fuel in daily operation. The variety of cabs, drive train configurations and suspensions offered by MAN is great, but so is the endeavour on the part of truck operators to find potential savings and optimise TCO independently of the model. For this reason, the new elements of the EfficientLine are also available for the majority of the two-axle tractors in the MAN TGX and MAN TGS series. Operators who need the fully air-sprung tractor with low fifth-wheel height, the "Ultra" model, for their transport tasks, or who would like to be able to select other cabs, XLX or LX, for example, or who want to mount bigger tank combinations on their frames - now they can all benefit from the insights of the MAN EfficientLine.