New buses switch to electric power in polluted areas
The first of two new hybrid electric buses have taken to the streets of Bristol.
The vehicles switch automatically from diesel to electric power in the most polluted areas. The city is the only one outside London to get the latest technology.
Although looking like normal double deckers with diesel engines, the buses use a form of sat-nav to switch to cleaner electric power when they enter congested zones with poor air quality.
The route runs between Bristol City Centre and the University of the West England in Frenchay. The bus switches between electric and diesel throughout the journey.
James Freeman from First West of England explains how the unique technology will work: