Transport for London has unveiled the country’s first zero emissions pure electric buses. The single-deck buses will run along the central 507 and 521 routes for a trial period from Thursday 19 December, connecting Victoria, Waterloo and London Bridge.

The buses take around 4 to 5 hours to charge and can drive 250 kilometres before running out of juice. That should be enough to run them all day and will offer a 75 per cent saving over diesel buses. There are 368 hybrid buses already in use on 25 London bus routes to reduce carbon dioxide by 30 per cent compared to conventional buses.

The BYD Auto buses will have zero exhaust emissions meaning lower overall carbon emissions - ideal for the centre of busy London. This trial is a step towards creating the London Ultra Low Emission Zone which the mayor has in mind. While things appear to be moving quickly we probably won’t see these buses in use everywhere until Eddie Izzard is mayor (yup, he’s running in 2019).

Mike Weston, TfL’s Director of Buses, said: "We will be closely monitoring the performance of these vehicles while they are being trialled here in London. Should the performance and reliability of these buses meet London’s challenging requirements, this could be a very important step towards adopting this new clean technology in the capital."

The trial should reveal if London’s tough demands are met by such buses. We believe this must mean exhibiting an ability to run all day, have enough to charge to make a route, recharge quickly, and handle that on repeat. Here’s hoping the Peckham Terminator doesn't decide to give them a test.

Two buses will be trialled from tomorrow with a further six added in early 2014.