In the 1940s, Swiss engineers developed a revolutionary electric bus that utilized large rotating flywheels to store energy instead of rechargeable batteries. This innovative design allowed for quieter and cleaner transportation that was not limited by overhead power lines. Bjarne Storsand, 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, measuring 160 cm in diameter and weighing 1.5 tons, 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. However, high energy consumption caused the system to eventually shut down in many places. Currently, only one gyrobus remains, restored and displayed at the Flemish Train and Bus Museum in Antwerp.
In contrast to traditional trams powered by overhead cables which restricted them to predetermined routes due to high installation costs of overhead power lines on new routes, Bjarne Storsand came up with an electric bus design using large rotating flywheels as energy storage units instead of rechargeable batteries.
The Gyrobus’s unique feature was its use of an electric motor powered by electricity generated by a flywheel generator that stored energy efficiently.
This innovative design enabled longer travel distances on a single charge compared to other electric buses at that time.
The Gyrobus had a large rotating flywheel measuring 160 cm in diameter and weighing 1.5 tons sealed inside a chamber filled with hydrogen at reduced pressure.
Charging was done quickly at around 40 minutes at charging stations along the route while replenishing power during operation took only 2-5 minutes.
However, gyroscopic effects made it challenging for passengers to change direction during turns but provided a smooth ride.
Gyrobuses were used widely in cities like Switzerland until they were eventually shut down due to their high energy consumption costs.
