The biggest gathering of super-green electric fuel-cell vehicles in Britain assembled for the opening of London's first ever hydrogen filling station on Tuesday.

Clean fuel firm ITM Power is cut the red ribbon to open the fill-up station at the National Physical Laboratory in Teddington.

It is part of a planned 'hydrogen superhighway' network of refuelling stations for pollution-free fuel-cell cars. Four more are planned to encircle London, and one already exists in Rotherham close to where Sheffield-based ITM Power is based.

Get your hands in the air - this is a fill up: Daily Mail motoring editor, Ray Massey, pictured using the ITM Power hydrogen filling station - the first of five planned around London

Transport Minister Andrew Jones officially opened the Teddington hydrogen fuel station on Tuesday, which uses excess or 'spare' electricity on the grid to generate industrial-scale electrolysis of water on-site.

This breaks down the water – or H2O – into its building block parts of hydrogen and oxygen. The hydrogen is then stored under pressure.

It means customers will be able to fill up their cars and pay at the pump, eliminating the need for fuel deliveries in London or anywhere else that has a filling station.

The fuel cell cars work by a process of 'reverse electrolysis' in that the hydrogen has a chemical reaction at a catalyst membrane in the car.

Ray Massey becomes first motorist to fill up a fuel-cell car at the new hydrogen filling station in Teddington ahead of its official opening

This produces energy in the form of electricity which powers the electric motors. The other residue is pure water – created by the hydrogen and oxygen atoms re-uniting to form H2O.

Toyota, Hyundai, Honda, BMW, and Daimler are among those who have developed fuel cell cars for general use by motorists.

Dashboard: The car is fuelled by hydrogen - and the waste they produce is water

Fill up: The filling station has hydrogen on tap, used to fill the eco-friendly cars

Advances: The fuelling station will make pollution-free cars more viable

New fuel: Toyota, Hyundai, Honda, BMW, and Daimler are among those who have developed fuel cell cars for general use by motorists

Rising demand: Electric fuel-cell cars could become increasingly popular as cities crack down on polluting vehicles

Refuelling at the site takes three minutes and fills the tank with 5kg of pressurised hydrogen at a cost of £10 per kilogramme, giving a range of between 300 and 500 miles, depending on model. A fill up costs around £50.

ITM Power chief executive Dr Graham Cooley said the target is to get the price down to £7 per kilogramme to make it cheaper than petrol and diesel.

He said demand for electric fuel-cell cars powered by hydrogen would grow as cities banned polluting diesel vehicles in future.

HOW DO YOU USE THE NEW HYDROGEN FILL-UP STATIONS? The hydrogen fuel-cell powered Hyundai ix35 and the Toyota Mirai are both available to purchase in the UK now and Honda launching the Clarity later this year. ITM Power has an agreement with Shell to deploy hydrogen stations onto Shell forecourts and a hydrogen fuel agreement with Toyota to supply hydrogen to their customers for free the first three years. The new station is publicly available and can refuel up to 16 vehicles a day. After a short training session, drivers of fuel cell vehicles will be able to use the station as and when they need fuel and they will be provided with a key fob to access the site and refuel. Motorists simply drive up to the station, pop the nozzle into the vehicle, press the screen to fill, the station will run safety checks and then refuelling will commence.

And despite fears about lighter than air but highly explosive hydrogen – which created lift for the ill-fated Hindenburg airship which exploded in flames – backers insist it is perfectly safe and in some respects safer than petrol as it does not 'pool' when spilt.

The new station has been part-funded by the taxpayer. And is part of the Hydrogen for innovative Vehicles – or 'HyFIVE' initiative which comprises 15 automotive, energy and industrial partners who will deploy 185 fuel electric vehicles from the participating manufacturers.

ITM Power's Dr Cooley said: 'This is the start of a quiet and clean revolution. Once it was considered acceptable to smoke in a pub and have other people breathe your fumes. No more. Soon it will be unacceptable for diesel cars to drive in city centres. That is why we are creating a network of hydrogen filling stations.'

Others are planned on the M25 near Cobham in Surrey, the M40 near Beaconsfield, the M11/A14 in Cambridgeshire, and at Rainham in Essex.

Paul Van der Burgh, Toyota (GB) PLC president and managing director, said: 'The opening of ITM Power's new filling station is an excellent example of how a coordinated hydrogen fuel infrastructure is successfully being developed in the UK.

'We are pleased to continue our support for the wider provision of hydrogen fuel outlets, which will encourage increased customer uptake of zero-emissions hydrogen fuel cell vehicles such as the Toyota Mirai saloon.'