In the 1940s, Swiss engineers developed an electric bus that utilized large rotating flywheels to store energy instead of rechargeable batteries. This innovation allowed many Swiss cities to rely on trams powered by overhead cables for public transport, which restricted them to predetermined routes. However, installing overhead power lines on new routes was deemed too expensive.
Bjarne Storsand, the chief engineer of Maschinenfabrik Oerlikon, came up with the idea of the gyrobus in 1946. The Gyrobus was powered by an electric motor that used electricity generated by a flywheel generator to store energy. The flywheel charged at a speed of 3,000 rpm at the charging station, allowing the bus to travel 6-10 km on a single charge. The flywheel measured 160 cm in diameter and weighed 1.5 tons and was sealed inside a chamber filled with hydrogen at reduced pressure to lower drag. Charging the flywheel took around 40 minutes while replenishing power during operation took only 2-5 minutes. Charging stations along the route ensured that the bus maintained its performance and speed.
Despite its innovative design, gyroscopic effects of the flywheel made it difficult for the bus to change direction, especially during turns. However, this system also provided a smooth and balanced ride. Gyrobuses were used in limited numbers in cities like Switzerland, Belgium, and the Belgian Congo until 1960 due to high energy consumption causing the system eventually shut down in many places. Currently, only one gyrobus remains restored and displayed at Flemish Train and Bus Museum in Antwerp as a reminder of an era when technology met innovation for cleaner transportation options.
Overall, this electric bus with its unique design revolutionized public transportation in Switzerland during its time but ultimately became unsustainable due to high energy consumption caused by its gyroscopic effects
