The world's first hydrogen double-decker buses will be introduced on three London bus routes next year, helping tackle the capital's air quality crisis.

Transport for London (TfL) ordered 20 of these green buses — which produce no pollution from their exhausts — as part of its drive to make London's transport zero-emission. It follows the introduction of the world's first Ultra Low Emission Zone last month.

The environment-friendly vehicles will be introduced on three routes, with people traveling to Wembley Stadium, or from west London to the West End, able to hop on the new green buses for a smoother and quieter journey. The new, modern buses will also enhance the customer experience, with on-board USB charging points making bus travel even more attractive.

TfL is investing $15 million in the new buses and the fuelling infrastructure. Wrightbus in Northern Ireland will manufacture them, creating new jobs in the region. More than $6 million of funding is being provided by European bodies and $1.3 million from the Office of Low Emission Vehicles.

To encourage the take-up of this trailblazing technology in other cities in the UK and Europe, TfL is leading procurement within the "Joint Initiative for hydrogen Vehicles across Europe" (JIVE) project. JIVE aims to bring down the cost of the vehicles by buying in bulk with other authorities — helping put the price per bus on a par with the other cleanest fuels.

Greening transport in the capital will require using a range of clean power sources. Hydrogen buses can store more energy on board than equivalent buses, meaning they can be deployed on longer routes. They only need to be refuelled once a day for five minutes, making them much quicker to power up when compared with conventional battery-electric buses.

The double-decker hydrogen buses will expand TfL's growing number of zero-emission buses. There are currently a total of 165 zero-emission buses, with a further 68 electric double-deckers on the roads by the summer. TfL has also recently announced that the route 323 will become fully electric next year, along with two further routes, which will be announced later this month.