Sono Motors, an electric vehicle maker with a focus on integrating solar PV with transportation, announced it has deployed its solar technology on the municipal bus fleet in Munich, Germany. The buses will be attached with a trailer that is topped with 20 semi-flexible solar panels.

The modules cover an area of 12 square meters and supply the 24V battery with over 2,000W. In this pilot, the solar energy generated will be used to operate the HVAC system and to support the trailer steering system. This saves the bus from burning diesel and stabilizes the battery’s energy supply, which lowers maintenance costs and extends battery lifecycle.

The PV system was custom-built for the needs of buses, and features the company’s proprietary maximum power point tracker (MPPT) unit and an algorithm-enabled charge controller designed to optimize energy production. Production can be tracked online through integrated software.

After technical approval by supervisory authorities, the bus trailer will go into regular service, providing cleaner transportation for Munich residents. “We need a change of course in the transport sector. Transport still misses the climate protection targets by a very wide margin, and this also has a direct impact on air quality in Munich. The solar buses can be a cornerstone in this urgently needed change towards climate-friendly mobility,” said Katrin Habenschaden, Munich vice mayor.

The company said a medium-sized fleet of 300 buses could save about 2,000 metric tons of C02 emissions each year. When considering the 1.5 ton C02 emissions “backpack,” or the amount of emissions related to producing the bus trailer, the carbon impact of production would be offset in less than one year of operation.

“The photovoltaic system on our bus trailer now allows us to test under real conditions how well the power generation works and whether there are perhaps routes in our network that are better suited than others for this type of power generation. The question of what energy savings can be achieved by using solar energy are, of course, particularly exciting against the background of current fuel and energy prices.” Veit Bodenschatz, Managing Director and Head of Bus Division of the MVG

Sono Motors said its solar technology has been designed so that it can be integrated with a large range of vehicles. E-buses can be integrated with PV on their roofs and sides, extending range, reducing standstill times for charging processes, and protecting the battery for a longer life through steady power cycling.

The company said it has signed more than ten letters of intent and contracts with companies like MAN, ARI Motors, and easymile. The company’s complete solution includes customized solar modules, power electronics, telematics and data, mechanical and electrical integration, and after-sales service. The technology is suitable for integration into existing vehicles and ready to be integrated with the production of new vehicles, said Sono Motors.

“Especially in times of rising energy prices and increasing urban area emission regulations, our solar technology offers great added value for public transport operators. City buses and coaches, whether electric or diesel-powered, offer a lot of space and are out on the road every day. The first solar bus trailer for MVG will hit the streets of Munich in the future and allow MVG passengers to experience solar mobility in daily use.” Laurin Hahn, co-founder and CEO of Sono Motors.

The Sion passenger EV

Sono Motors is also developing its own passenger vehicle, the Sion. The Sion sports a liquid cooled battery with a 54kWh battery and a 190 mile range and has 248 solar cells seamlessly integrated in the roof. The PV on the roof can add between 70-150 miles per week to that range.

The car can be charged 80% in 35 minutes via a fast charger, and is capable of public charging, at-home charging, and can exchange power vehicle-to-vehicle. Preorders are available in the German market.

Sono said the former SAAB plant that will be used to produce the Sion will be powered by 100% renewable energy.