Photovoltaics for truck roofs
Unlike cars, which have hardly any surface area for photovoltaics, installing PV modules on trucks can be worthwhile. The Fraunhofer Institute for Solar Energy Systems ISE has now built Germany's first solar truck. The particularly lightweight PV modules for the vehicle were developed by the Fraunhofer Institute for Transportation and Infrastructure Systems IVI together with partners from industry. The vehicle weighs 18 tons and has a 3.5-kilowatt system installed on the roof, which is expected to cover between 5 and 10 % of the truck's energy needs. The photovoltaic system feeds directly into the 800-volt traction battery. In the future, the solar truck will be driving in the Freiburg area for an electric wholesaler.
To achieve the highest possible electricity yields, the solar modules in the vehicle roof were connected in series. Since the resulting voltage of up to 400 volts could pose a danger in the event of an accident, researchers at Fraunhofer ISE developed a disconnection device. This was installed in the junction box of each photovoltaic module and disconnects the power connection locally in the event of an accident to prevent possible electric shocks.
The scientists from Fraunhofer ISE will verify the electricity yield prediction over a period of one year and test the components under real conditions. They will use an energy prediction model that calculates the range as well as electricity production and charging times of the truck depending on vehicle consumption and solar radiation.
Sources: pv-magazine, article by Ralph Diermann from 10/25/2021: https://www.pv-magazine.de/2021/10/25/fraunhofer-ise-nimmt-lkw-mit-photovoltaik-dach-in-betrieb/ (last access on 10/27/2021 at 10:35 a.m.)
https://www.wissenschaft.de/technik-digitales/erster-solar-lkw-auf-deutschlands-strassen/ (last access on 10/27/2021 at 11:00 a.m.)