Transport for London (TfL) has ordered 20 hydrogen-powered buses to help cut air pollution in the capital.
The buses are to be introduced on routes to Wembley Stadium, or from west London to the West End, and will be the first hydrogen-powered double-decker buses in the world.
A £12M contract to build the buses was awarded to Wrightbus, in Northern Ireland, with £5M provided by European bodies and £1M from the Office of Low Emission Vehicles.
The hydrogen vehicles have a much longer range than TfL’s current fully-electric buses, and are able to complete a full day serving longer routes with only one five-minute refuelling stop.
The buses produce zero-emissions from their own exhaust. The only byproduct of the combustion process which drives their engines is water.
But the main process of producing hydrogen for fuel typically uses electricity to power electrolysis, which separates hydrogen and oxygen molecules in water.
The energy for this process can come from burning fossil fuels like gas, or from renewable sources.
Even when using fossil fuels are used, the overall carbon footprint of hydrogen vehicles is still much lower than conventional combustion engines.
London mayor Sadiq Khan said: “Following the launch of the world-first Ultra Low Emission Zone last month I’m delighted that TfL has today signed a contract to bring 20 state-of-the-art, zero-emission hydrogen buses to London’s streets. We are investing a record £85M in cleaning up our bus fleet, and I am proud that London now has the largest zero-emission bus fleet in Europe.”
TfL director of bus operations Claire Mann added the scheme would help make greener buses cheaper for other authorities. “London has the cleanest bus fleet in Europe, but we know we need to go further and faster to tackle the public health emergency caused by dirty air. Innovating and using hydrogen means we have flexibility in matching the right fuel with the operational requirements of the network.
“We are also pleased to be leading an initiative that brings down the cost of buying the greenest buses across the Continent and within our own country, as we know pollution doesn’t respect national or local boundaries.”
There are currently 165 zero emission buses in London, with a further 68 electric double-deckers set to be on the roads by the summer, with all buses set to be upgraded by October 2020.
Hydrogen trains are also being developed for use in the UK, with existing rolling stock being retrofitted to use hydrogen fuel and batteries. While Northern Powerhouse Rail is also backing the use of hydorgen technology in its plans.
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