26 Oct 2021
Fraunhofer institutes equip 18 ton truck with a 3.5 kW peak PV system; now undergoing test drives on Freiburg streets.
A heavy-duty truck weighing 18 tons and equipped with a 3.5 kilowatt-peak photovoltaic system is now driving on Germany’s roads. The commercial vehicle with integrated high-voltage photovoltaic system and feed-in to the 800V traction battery has been approved for road traffic.
The Solar power produced directly on the vehicle can cover 5 to 10 percent of the truck’s energy needs. In the Lade-PV project, the Fraunhofer Institute for Solar Energy Systems (ISE), with its project partners from industry and the Fraunhofer Institute for Transportation and Infrastructure Systems (IVI), has developed Solar PV modules and power electronics for integration in commercial vehicles.
The developers say that the truck – the first such equipped with these PV modules – has now passed the technical inspection, marking what they describe as “a milestone towards more climate-friendly road freight transport.”
Christoph Kutter, project manager at Fraunhofer ISE, commented “By successfully putting our high-voltage photovoltaic system into operation, we have achieved our goal of demonstrating the feasibility of vehicle-integrated photovoltaics for heavy-duty electric utility vehicles. The technical components integrated into the truck function as expected.”
The particularly lightweight and robust PV module prototypes were developed by Fraunhofer ISE and built by Sunset Energietechnik. TBV Kühlfahrzeuge integrated the new modules into the box body of a Framo electric truck, which is serving as the first demonstrator vehicle.
Safe power management
To ensure that the electricity yields are high and the material and cabling costs are low, the Solar modules in the truck roof are connected in series. The resulting high voltages of up to 400V could pose a safety risk in the event of an accident.
In order to avoid this, Fraunhofer ISE has developed a separation device, which is located in the junction box of each PV module. In the event of an accident, the device disconnects the power within milliseconds, so that only harmless, low protective voltages are present throughout the system.
As with the PV modules, the power electronics were also adapted to the requirements of the commercial vehicle. Project partner M&P Motion Control and Power Electronics GmbH developed a DC power controller that communicates with the vehicle control system via CAN bus and is integrated into the vehicle’s safety concept. The photovoltaic power generated on the roof is fed directly into the on-board power supply of the commercial vehicle.
One-year road test
The truck with integrated photovoltaic system will be used …….