London's red double-decker buses are going green. No, we're not talking about a change to their iconic paint-jobs: Mayor Boris Johnson today announced plans to introduce an all-electric model in the capital. London is already served by hundreds of hybrid and eight all-electric single-decker buses, but the new double-decker variant is set to be a world first. That's not surprising, given such a large and heavy vehicle will require more, or higher capacity batteries to continue picking up passengers throughout the day. (Wireless charging can only help so much.) The new vehicle is being developed by BYD and will be trialled on route 16 between Cricklewood and Victoria Station from October.