A BYD Co Ltd badge is seen on an e6 all-electric vehicle in New York, on Friday, Dec. 20, 2013. [Photo/VCG]

Chinese automotive manufacturer BYD officially launched 51 new single decker electric buses on Friday, which it said would be Europe's biggest all-electric bus fleet so far, saving London 700 metric tons of CO2 emissions a year.

The new fleet was launched after BYD's initial supply of two electric buses to London three years ago proved a success in reliability and consistency in running a 16-hour shift without a recharge being necessary.

London's deputy mayor Val Shawcross, who looks after the city's transport, attended the launch ceremony.

The 51 buses will be operated by London bus operator Go Ahead from its Waterloo garage, servicing two Transport for London routes - 507, which connects Waterloo with Victoria, and 521linking Waterloo and London Bridge.

When BYD supplied the single decker buses to Go Ahead three years ago, it also helped Go Ahead with installing the charging stations.

Apart from the single decker buses, BYD is testing the world's first pure electric double decker fleet of five buses in partnership with London bus operator Metroline.

BYD's initiative also highlights the green vehicles China is developing and expanding internationally.