When fully converted, the electric buses on routes 507 and 521 will deliver a reduction of 408 tonnes of CO₂ and 10 tonnes of NO_x per year, when compared to single-deck diesel buses. The electric buses are emission-free at tailpipe, and will provide passengers with an improved experience with lower noise and vibrations.

The announcement follows the recent introduction of the first of two new electric buses, manufactured by Spanish company Irizar. Mayor of London Boris Johnson also announced a world-first trial of a purpose built pure electric double-deck bus that will begin in October. (Earlier post.)

The two Irizar single-deck buses will operate on routes 507 and 521, which link Waterloo station to Victoria and London Bridge stations respectively. The new buses will join two existing electric buses, manufactured by Chinese company BYD, on the Go Ahead-operated commuter routes in central London. Including the first Irizar bus now in service, there are currently 9 single-deck electric vehicles in the fleet will grow to 17 in September. Once the double-deck trial begins in October, there will be 22 total pure electric buses on London streets.

A further six electric single-deck buses, manufactured in the UK by Optare, are already in the TfL fleet. Four of them operate on route H98 in west London and two serve route 312 in south London that later this year will become the Capital’s first all-electric bus route.

The Capital’s bus fleet already has over 1,300 hybrid electric buses and over 1,400 older buses have been retrofitted, reducing their emissions by up to 88%. The number of hybrid buses will increase to over 1,700 by 2016—a figure that represents more than 20% of the fleet. This includes 800 New Routemaster buses, which are one of the cleanest double deck buses of their type. By 2016, when all 800 New Routemasters are in passenger service, these vehicles will reduce CO₂ emissions by 27,500 tonnes a year.

In addition, there are eight hydrogen buses operating on route RV1, between Covent Garden and Tower Gateway. In the autumn TfL will be trialing inductive charging technology that will enable special extended range diesel electric hybrid buses to wirelessly charge their batteries while they wait at bus stands. The technology will be trialled on up route 69 in east London, which runs between Canning Town and Walthamstow bus stations.

TfL has also accelerated the introduction of ultra-low emission Euro VI buses—with more than 500 in service. The effectiveness of Euro VI engines in reducing harmful emissions has been substantiated in testing by TfL that re-creates real world driving conditions in London. During this testing, a bus with a Euro VI Engine was found to have 95% lower NO_x emissions than a bus with a Euro V engine (down from 10 g/km to 0.5 g/km).

London Buses now carry around 2.4 billion passengers a year, which equates to half of all bus journeys made in England. In recognition of the continued need to invest in bus services—with a increase in demand from the city’s rapidly growing population—TfL’s latest Business Plan has dedicated around £500 million (US$79 million) to improve the network over the period from 2015/16 to 2020/21.

This will include funding for more than 500 extra buses, which will create capacity for an extra 2.9 million customer journeys each week.