Chinese auto giant BYD said today that it has delivered 29 all-electric double-deckers to Britain's bus operator  National Express in cooperation with local bus builder Alexander Dennis Limited (ADL).

The first 19 double-deckers are already in operation in Birmingham, the UK's second-largest city, and the remaining 10 units will be put into use in Coventry, central England, this fall.

So far, BYD has sold more than 250 electric double-deckers in the UK, two-thirds of which are in operation.

The busses are 10.9 meters long, have 65 seats, and are equipped with USB charging ports and free wireless networks.

They will be recharged entirely from renewable energy sources and equipped with an energy storage system that can also be used to balance the load on the electricity grid.