Photovoltaic modules complement diesel generators in trucks
The enormous cost reductions in photovoltaic modules make the use of solar energy in the mobility sector more attractive. Even diesel fuel in the commercial vehicle sector can be partially replaced by photovoltaics, depending on various parameters on the application. The Fraunhofer ISE carried out a yield analysis for the PV power supply of commercial vehicles, eg refrigerated transporters, with real-measured irradiation data. On the basis of the results, the institute sees significant potential and is now researching together with partners from the logistics or automotive industry on special PV modules for use in the commercial vehicle sector. These are to be installed on the roof surfaces of commercial vehicles and can supply electricity for the drive of the vehicles or the cooling of goods.
The use of photovoltaics in commercial vehicles can help reduce diesel consumption, save costs, reduce CO2 emissions in commercial vehicles, and thus achieve environmental and climate change in the transport sector, concludes Matthieu Ebert, Team Leader Module Efficiency and New Concepts at Fraunhofer ISE. “With the development of a solar-powered vehicle body, we want to make photovoltaic technology available for road transport and to help reduce logistics costs,” he says.
While previous profitability studies for PV applications in the commercial vehicle sector were based on simulations with synthetic weather data, the Fraunhofer ISE has commissioned several truck trailers with irradiation sensors, in cooperation with logistics company Dachser and forwarder Benzinger, to put the irradiation potential in the real logistics. For more than half a year, irradiation data on trucks underway across Europe and the United States were collected and evaluated. Fraunhofer ISE evaluated the data according to various criteria. “If the resulting irradiation data and the roof areas potentially equipped with PV modules are combined, reliable results can be made about the viability of such systems,” says Ebert. “On the basis of our calculations, we assume that a 40t cooling trailer with a roof area of 36 m 2 equipped with PV modules (rated power of 6 kW) can save up to 1900 liters of diesel,” says Ebert. Important findings from the study, presented at the European Photovoltaic Solar Energy Conference and Exhibition EU-PVSEC 2017 and the “Lkw und Fuhrpark” conference, are that the diesel savings and thus the profitability depends heavily on the usage area and on the usage scenario of the vehicles . With the findings gained from the measurement campaign, Ebert and his team will be able to advise future logistics companies on the question whether the use of PV is economically viable for them and which PV technology is best suited for them.
The vehicle-integrated PV modules to be developed must be as light as possible and at the same time offer high efficiency in order to keep the additional weight of the coolers low. In addition, a special design is required to install the PV modules on the vehicle roof while maintaining the maximum height according to road traffic regulations. They must be very compact in design and resist dynamic mechanical loads, eg vibrations by driving.
The project was funded by Fraunhofer Zayed Progamm and carried out in collaboration with Fraunhofer CSE in Boston.
SOURCE: Smart 2.0.