DAF puts the LF Hybrid truck into production
DAF will start production of the DAF LF Hybrid, a 12 tonne distribution truck with a parallel hybrid system, before the year is out. This follows a comprehensive field test where vehicles have been tested for two years in the most diverse practical applications in daily use with customers in Great Britain and on the Continent. The use of hybrid technology can lead to a reduction in fuel consumption and therefore CO2 emissions of between 10 and 20%, depending upon the application. DAF is one of the first European truck manufacturers to put a hybrid truck into production.
PACCAR – DAF’s parent company – is leading the way in the field of hybrid technology. In the United States, the Kenworth and Peterbilt brands offer a range of models where using diesel/electric hybrid technology significantly reduces fuel consumption and emissions. As part of PACCAR's international hybrid programme, the DAF LF Hybrid truck was developed in close collaboration with Eaton, Eindhoven University of Technology and Leyland Trucks Ltd, also a PACCAR company.
EEV diesel technology
The DAF LF Hybrid uses a parallel diesel/electric hybrid system, where the truck is driven by the diesel engine, the electric engine or a combination of both. The truck is fitted with the 4.5-litre PACCAR FR diesel engine, which complies with the ultra-low EEV emission requirements as standard, without a soot filter. In the LF Hybrid, this engine produces a maximum power of 118 kW/160 hp and is linked to an automatic Eaton six-speed gearbox (Autoshift).
An electric motor has been installed between the clutch and the gearbox, which can provide drive as well as functioning as a generator. Energy released during braking is stored in the lithium-ion batteries and reused when accelerating. Depending on the degree of charge of these lithium-ion batteries, a central computer determines when the diesel engine provides the drive and when and to what extent the electric motor is used.
Lithium-ion batteries
The battery pack for the hybrid system weighs around 100 kilos and consists of ninety-six 3.4 Volt cells. When these batteries are fully charged, the LF Hybrid truck can travel about two kilometres electrically without needing the diesel engine to drive it. In practice, this is enough to drive in and out of the "green zones" in city centres. In these types of circumstances, the diesel engine also runs at idle in order to drive various components (such as the steering pump and the air compressor). The LF Hybrid is also fitted with a start/stop system.
In addition to the battery pack, DAF hybrid technology consists of a current transformer that converts the alternating current supplied by the generator to direct current for the batteries. A cooling unit is also fitted to the chassis to cool this current transformer. The DAF LF45.160 Hybrid is only 300 kilograms heavier in total than the standard model with a diesel engine alone. Because the DAF LF series is famous for its favourable unladen weight, the 12-tonne LF Hybrid nevertheless offers a very useful load capacity of around 7.5 tonnes.
Field test demonstrates reliability
As is DAF standard practice, the development programme for the LF Hybrid was concluded with a comprehensive field test. In addition to extensive test programmes ten vehicles were used to gain practical experience by customers in Great Britain and on the Continent for a range of distribution applications over a two-year period. First and foremost, the field test demonstrated the reliability of DAF hybrid technology but also - depending on the application - that savings in fuel consumption and therefore CO2 emissions of between 10 and 20% were achieved.
Another advantage of hybrid technology is that components susceptible to wear, such as brake linings and the clutch plate, will have a longer service life because braking occurs on the electric motor.
Operational lease
DAF is starting to supply the LF Hybrid in Great Britain, the Netherlands, Germany, France and Belgium; countries where market research has shown that the interest in hybrid vehicles is highest. Depending on the success of the LF Hybrid in these markets, DAF will decide whether to include the vehicle in the standard product range in other countries.
Hybrid technology will be developed further in the next few years, particularly when it comes to the batteries. This is why the DAF LF Hybrid is offered as standard via PACCAR Financial with a full operational lease contract, so that the DAF dealer can implement any potential updates during the contract term. This ensures that transport operators always have the most environmentally friendly vehicles for a fixed price per month.