New fuel cell double-decker buses are coming to London next year. They are manufactured in Northern Ireland by Wrightbus, which also exports them across the globe.

There are already single-decker fuel cell buses serving the RV1 route (which is to be withdrawn next month) and the plume of water vapour they emit is slightly reminiscent of steam trains.

Emissions control in London continues to tighten, with the Ultra Low Emission zone in Central London and the Low Emission Zone throughout Greater London.