The solar bus kit from Sono Motors is a retrofit solution in which photovoltaic modules are installed on bus roofs. The energy generated is fed directly into the on-board power grid and is intended to reduce fuel consumption and CO₂ emissions.
After comprehensive tests by the Federal Motor Transport Authority (KBA) in cooperation with the Technical Inspection Association (TÜV), the solar bus kit received general operating approval. Previously, the integration of solar technology into public transport was considered non-approvable by the type approval authority, as neither test criteria nor a standardized procedure existed. Sono Motors has managed to overcome this hurdle by defining and successfully carrying out all required and extensive tests using the solar bus kit as an example. With this certification, street approval for the solar bus kit can be easily obtained in other ECE states as well.
“Setting new standards for sustainable mobility”
The solar bus kit promises to save fuel, reduce CO₂ emissions, and improve bus range by relieving the alternator.
“Obtaining general operating approval for our solar bus kit is a milestone for Sono Motors and the entire industry. With this, we are setting new standards for sustainable mobility and once again demonstrating our innovative power,”
comments Denis Azhar, Managing Director. Sono Motors aims to set new standards in sustainable mobility with the solar bus kit by combining innovation, safety, and efficiency.
Reorientation after the Sion
After discontinuing the Sion solar car program in early 2023, the company founded in 2016 reoriented itself: Sono Motors has since focused on the development and delivery of the solar bus kit, the retrofit product specifically developed for buses for solar integration – and thus pursues the mission “Solar on every vehicle”.






