The American company Proterra developed an electric bus called Catalyst, which not only measures up to hybrid and traditional fossil fuel busses, but beats these in many aspects.

They say its engine is six-times more efficient than the conventional diesel- or LPG-powered engines, while it uses 1.7 kWh of electric power per mile or a kilowatt hour per kilometre. Its lithium-ion battery can store from 53 to 321 kWh of power, with which it can operate up to 290 km. The efficiency in everyday city traffic was also increased with Proterra's Terra Volt charging platform, which provides the capacity between 53 to 131 kWh of power in all of 10 minutes.

Since city busses have to overcome different terrains, the data on performance are also impressive. A 20-tone bus exceeds the speed of 30 km/h in 6.6 seconds and apparently can take on 15.5 percent gradient, outshining many competitors with internal combustion engines.

.