The silent blue vehicles, powered by batteries and capable of transporting 22 people, were chosen to replace vans that previously plied the route’s narrow cobbled streets.
The Italian made Breda Menaribus ZEUS (zero-emission urban system) buses are designed to run all day on a single charge.
City council agreed to foot the 467,000-franc ($484,000) bill for the buses in the interests of having quiet, pollution-free ways to move people about in the historic centre.
More buses could be on the way because council in 2012 voted a credit of 960,000 francs to introduce small electric buses not only on route 36 but on routes 32 and 35 as well.
The buses are recharged at a station near the Parc des Bastions, a park adjacent to the Old Town.
They are just the latest models in a TPG fleet that includes electric trolley buses, as well as the wireless prototype being tested in the area around the Geneva airport and the Palexpo convention centre.
The TOSA bus is designed by ABB Sécheron and developed with TPG and the canton’s utility company SIG.
It is an articulated bus, capable of carrying 133 passengers, that fully recharges in 15 seconds at every stop through an overhead “flash” system.