The reduction of costs of the modules makes the photovoltaic more and more attractive for the mobility sector. The Institute Fraunhofer for Solar Energy Systems (ISE) has evaluated the performance of photovoltaic systems for commercial vehicles (eg refrigerated transport trucks) using actual solar radiation data. The best of all is that the accounts come out.
Fraunhofer ISE has discovered great potential in this sector, and is working piecemeal together with other companies in the automotive and logistics sector to integrate photovoltaic modules in commercial vehicles. The objective is to install them on the roof to support the motor with solar energy or to cool goods (food among other things).
The use of photovoltaic solar energy in these heavy trucks can contribute to reduce diesel consumption and CO2 emissions.
And in this way comply with environmental and climate protection regulations in the transport sector. According to Matthieu Ebert, Head of the Module Efficiency and New Concepts Team at Fraunhofer ISE, “With the development of a solar body we want to make photovoltaic technology available of the logistics sector and contribute to lower costs",
Other studies on the economic viability of this type of application have been based, to date, on simulations with artificial weather data. Fraunhofer ISE has worked in collaboration with the logistics company Dachser and the truck company Benzinger. In addition, it has equipped several trailers with sensors to measure the potential of heat stroke in real life.
In an economic feasibility study Fraunhofer ISE equipped six 40-ton refrigerated trucks with solar radiation sensors, who followed their usual routes through the United States and Europe - from Prague to Mallorca, from Paris to Munich - for half a year. And then he evaluated the data.
"When you merge the data collected from roofs that could be equipped with photovoltaic modules, you can see the feasibility of these systems," explains Ebert. "With our calculations, a 40-ton refrigerated trailer with a roof area of 36 m2 equipped with photovoltaic modules (nominal power of 6 kW) could save up to 1.900 liters of diesel fuel per year ”.
An important finding of the study, which will be presented at EU-PVSEC 2017 and at the 8th Conference 'Lkw und Fuhrpark' is that fuel savings and, therefore, the viability of the initiative, largely depends on the vehicle deployment regions and usage scenarios. In the future, the knowledge gained from the measurement campaign will allow Ebert and his team to advise logistics companies on this issue.
Specific design for each vehicle
To minimize any additional load on the trucks, it would be necessary to develop integrated photovoltaic panels that are as efficient and efficient as possible. What's more, A design will be needed to allow the photovoltaic modules to be installed on the roofs of the trucks without exceeding the maximum heights allowed by the DGT regulations. The modules have to be extremely compact and able to withstand dynamic mechanical stresses caused, for example, by vibrations during movement.
Fraunhofer ISE is supporting the development of these modules. Ebert and his team offer field tests to interested companies and collaborating partners, so they can see the results on-site and can calculate the potential cost savings. The project has been funded by the Fraunhofer Zayed Program and carried out in collaboration with Fraunhofer CSE in Boston.
Highways with solar roofs
The world has put the batteries in the search for how make the most of clean energy. In this context, this impressive project called "Solar Serpent", devised by the architect Mans tham for the city of Los Angeles.
Cover roads, highways and railways with solar photovoltaic covers It is already an option with the odd installation in operation, as is the case of a high-speed train line in Belgium covered by the Enfinity company and inaugurated in June 2011.
In other parts of the planet it is studied as solution to the maintenance of transport infrastructures without increasing taxes and as a means of producing clean energy without affecting the landscape. Mans tham is the Swedish architect and urban planner who has proposed and developed the project for solar roofs for highways.
The Swedish architect and urban planner has embodied a project applicable in all areas with many hours of sunshine a year, which consists of take advantage of the highways to provide them with solar roofs that produce energy, reduce the cost of road maintenance, lower the consumption of air conditioning in vehicles, improve road safety and the risk of accidents and capture the CO2 generated by exhaust pipes.
Olivier Daniélo has published a documented study of the Mans Tham project in February 2016 on the French site Techniques-Ingenieur, in which the advantages and savings that the solar snake supposes for the roads are detailed, as its author calls the roof that we have been commenting on. Solar roofs that act as a noise pollution barrier for nearby inhabited areas, support for lights and vertical signage, rainwater collection and many other derived savings such as reducing the fuel consumption of vehicles when lessen the impact of the wind, rain, hail or snow.
All the discomfort caused by the sun at dawn and dusk would be largely avoided, as well as overheating of engines in areas with high insolation such as deserts and warmer countries. All the advantages mentioned come up against the lack of political will to undertake transcendental changes for the majority due to the pressure of the industrial sectors that would be affected in their income: road maintenance companies, electricity companies, construction companies of public works that contemplate other alternatives such as solar panels installed on the road.
