Three fire trucks with Volvo Penta electric drivelines heading to Berlin, Amsterdam and Dubai to begin customer testing
25 September 2020
Volvo Penta has developed an electric driveline for leading fire service vehicle manufacturer Rosenbauer’s pioneering fire truck, named “Revolutionary Technology” (RT). The truck was officially launched at an event in Austria. The RTs will now be sent to fire departments in Berlin, Amsterdam and Dubai to begin real-world customer testing.
By walking away from conventional commercial vehicle concepts and developing an electric solution for the truck’s driveline, Volvo Penta and its customer Rosenbauer have introduced a completely new vehicle architecture for the fire service industry.
With its electric driveline, the fire truck features excellent ergonomics, functionality, and safety, as well as high loading volumes, compact dimensions and one-of-a-kind agility. The Volvo Penta electric driveline also brings benefits such as zero exhaust emissions and significantly reduced noise levels.
The Volvo Penta-powered RT features two electric motors that have the potential to provide a total output of up to 360 kW (490 HP) and up to 50,000 N·m for all wheels. A two-speed gearbox ensures that the full torque is available even when starting off on hills, and that there is enough traction for steep gradients.
The RT is equipped with one, or optionally two, high-voltage battery storage units, each with a capacity of 50 kWh, which not only feed the traction drive but also provide electrical energy at the drafting point. Several external devices, such as fans or submersible pumps, with a total power consumption of up to 18 kW can be operated simultaneously via the power outlet.
The extinguishing water pump can be operated either electrically by means of a generator or by the range extender (diesel engine). For shorter fire-fighting operations, the energy of the RT in the 100 kWh version is sufficient. For longer operations, the range extender is employed, which consists of a six-cylinder diesel engine with an output of 200 kW (272 HP) and a power generator.
With this tandem, the RT becomes a fully integrated power plant that is able to automatically recharge its batteries when more energy is consumed than they store. As a result, the RT achieves operating times above the specifications of EN 1846.
External charging of the RT’s batteries can be carried out either by means of alternating current from standard industrial power sockets or using suitable direct current charging stations. With a full charging capacity of 150 kW, just a quarter of an hour is sufficient to raise the charge level of both high-voltage batteries (100 kWh) from 50% to 80%.
The RT has a low-floor chassis with a tubular frame between the two axles, in which a traction battery weighing around 550 kg is installed. This results in a much lower center of gravity than that of firefighting vehicles built on truck chassis, and keeps the RT safely on the road, even during rapid cornering.
The RT owes its high maneuverability to the independent wheel suspension developed especially for this vehicle. This allows a practical combination of the requirements in terms of suspension, steering angle and all-wheel drive. The independent wheel suspension enables a significantly larger steering angle and thus a smaller turning radius compared to conventional vehicles with all-wheel drive. It also offers better ride comfort and driving dynamics compared to a rigid axle.
On the RT with the shortest wheelbase (3,800 mm), the turning circle diameter is approx. 15.00 m, and with rear axle steering activated this is reduced to just 12.50 m. This optimizes maneuverability in narrow alleys and enables precise maneuvering in so-called crab steering (diagonal steering) mode.
Another special feature of the RT is its air-sprung chassis with selectable ride levels. This allows the underaxle clearance to be adapted to the terrain or situation when driving: the distance can be set to 250 mm for road travel, 350 mm for travel through rough terrain, and 470 mm for crossing flooded roads (Watt mode).
On the other hand, the chassis allows the RT to be lowered to an underaxle clearance of 175 mm at the drafting point, in order to reduce the entry height of the cab to a minimum. This allows the crew cab to be entered safely and comfortably at a fast pace, and eliminates a potential risk of injury, as there is no need to climb stairs as with conventional vehicles of this size.
As part of the Volvo Group, Volvo Penta leveraged proven technology and competence from Volvo Trucks and Volvo Buses, and adapted it to meet the performance requirements of a fire service application. The result is a proven Volvo Group technological solution that is tailored to meet Rosenbauer’s specific needs.