The buses, which emit water vapour only, are being tested on the streets of London, Amsterdam, Barcelona, Berlin, Hamburg and British Columbia.

While still prohibitively expensive to be used on larger scales, hydrogen fuel cell buses are already serving regular London bus routes as part of a successful trial that is now nearing its end.

Hydrogen fuel cells are carbon neutral provided that the hydrogen is procured using a carbon-neutral method, but most hydrogen still has to be produced using energy derived from fossil fuel sources such as natural gas. This approach still produces much lower emissions than traditional buses overall as well as cutting out urban pollution.

But there are perspectives for making hydrogen buses both cheaper to run and carbon-neutral in the near future. A recent study in London pointed to the possibility of making hydrogen for use in fuel cells completely carbon-neutral, by using energy derived from the capital’s waste.

Deputy Mayor Nicky Gavron, chair of the London Hydrogen Partnership said: “The Mayor and Transport for London are committed to improving public transport and to cutting harmful emissions.

“We are already working to introduce 70 hydrogen vehicles to London. This Memorandum of Understanding shows our commitment to this new technology.

“In London we cannot continue to throw our rubbish into vast landfill sites which are responsible for 20 per cent of the UK’s emissions of the harmful greenhouse gas – methane.

“In London we have a growing amount of waste and if we can produce renewable hydrogen from this, it will play a large part in cutting harmful emissions and managing our rubbish in a sustainable way,” she said.

Goska Romanowicz

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