Belgian company MSIE sells flexible solar films that can be installed on the rooftops of buses and coaches. Goal? To generate electricity to power all electric appliances on board a bus or coach like HVAC, electronic devices etc. and thus saving on fuel consumption.
The film can be bent to a maximum of 30°, it has a thickness of only 1,4 mm and it weighs 2,4 kg per sqm. One module measures 1m x 1.70m or 1m x 2m and can generate 400 watt per sqm. On an average bus, six modules can be installed, which reduces fuel consumption with 5 to 10 percent and reduces CO2 emissions with 4,5 to 6 tons.
The film is easily installed with silicone glue or self-adhesive velcro. There is no need for a metal mounting system like with inflexible solar panels.
Positive test cases
Keolis Denmark tested the solar film on Iveco diesel vehicles and evaluated it positively. Malta Public Transport just started a trial on its Otokar buses.
Another test was done by the German FlixBus. FlixBus installed solar films on one of its buses that runs from Dortmund (Germany) to London (UK). The solar mats communicate with the alternator in the bus through a charge controller placed in the FlixBus. This way, the bus battery is mainly charged by solar energy, relieving the alternator of the need to charge it using fuel. FlixBus indicated that an average of 1.7 litres of diesel was saved per 100 km. With an average distance of 600 kilometres per day, this adds up to a daily fuel saving of around 10 litres. And it was not even summer yet.
Not only the operator benefits, the climate wins too.
By generating extra 100% renewable electric power, for operations the fuel costs will decrease as well as the maintenance cost, since the alternator will be used less often or not at all and battery life is extended with 20 percent.
And for the climate... that's easy to understand: replacing fossil fuel by renewable electricity is always a win.