A ferry powered by hydrogen could soon be making waves in Bristol's Floating Harbour.

Bristol City Council wants to trial the environmentally friendly fuel and has appealed for companies to take part in the project.

The authority believes using hydrogen, rather than diesel, can cut pollution and make for quieter and fume-free ferry journeys.

If the six-month trial is successful, hydrogen-powered electric ferries could be introduced to the city docks permanently.

Hydrogen already powers ferries in Hamburg and will soon be used on boats in Amsterdam.

The city council will pay a consortium made up of a ferry operator, hydrogen fuel cell specialist and hydrogen supplier to take part in the trial.

A ferry fuelled by hydrogen could be carrying passengers on the Floating Harbour from the autumn.

It would run for 42 hours over a six-day week to test out the technology and make sure it is reliable.

Councillor Jon Rogers, executive member for transport and sustainability, said: "We are looking at alternative environmentally friendly technologies for all Bristol transport.

"The harbour is a great place to trial a new innovation which sends this message, as it draws crowds and is enjoyed by hundreds of thousands of people every year. Bristol has a long history of maritime innovation and this is hopefully the next step. We want to show that Bristol is a place to try out new environmental technologies, creating new jobs while combating climate change, peak oil and other environmental concerns.

"We are hopeful that the ferry will also reveal other hydrogen-based opportunities, maybe including the next generation of rapid transit."

Councillor Neil Harrison, assistant executive member for sustainability, said Bristol's six ferry operators, including the Bristol Ferry Boat Company, the Bristol Packet Ltd and Number Seven Boat Trips, had all been invited to bid to take part in the trial.

He said the trial could involve a brand new hydrogen-powered vessel or an existing ferry modified to take hydrogen as its fuel.

But Rob Salvidge, co-owner of the Bristol Ferry Boat Company, said he was not convinced by hydrogen as a fuel for boats.

He said: "It don't think the technology works. It sounds fantastic but the problem is the production, transport and storage of the hydrogen. It takes energy to produce and that blows out the advantages. There are more viable forms of energy such as water-powered turbines.

"However, I praise the council for looking into it and want to get involved in the discussions and debate."

● Hydrogen fuel cells are batteries which use hydrogen and air to produce electricity, with water the only waste product.

● It can be produced in many ways – including conversion from natural gas, through the electrolysis of water, and from waste.

● Hydrogen is a gas and is stored in bottles. The bottles can be fitted to a ferry and electricity is created to power the vessel's engine.

● Hydrogen fuel cells can also be used to power vehicles including cars and buses.

● An estimated 60 per cent or more of the energy produced in a hydrogen fuel cell goes to powering a vehicle, compared with 20 per cent from most internal-combustion engines.