Finally, a sleek, affordable British-built hydrogen-powered electric city car has arrived.
Hitting the roads from today, the electric car will reduce emissions, with just water coming from its exhaust, and it even has DeLorean-style gull wing doors.
Called Rasa, the green vehicle runs on electricity generated by hydrogen fuel cells and gives the equivalent of '250 miles to the gallon', according to its backers.
The two-seater will travel 300 miles (482km) on one 1.5kg fill-up of the lighter than air gas - which was once used to provide the lift in Zeppelins until the Hindenburg disaster of 1937.
The car has no gears, just buttons for forward, neutral or reverse, plus an accelerator pedal and brake. It can accelerate from zero to 60mph (97km/h) – the city car's top speed - in 10 seconds.
Named after the Latin for 'clean-slate', the futuristic-looking Rasa has been developed from scratch over 15 years by engineers and entrepreneurs at Riversimple Movement based in Llandrindod Wells in Wales.
Initial plans are to lease thousands of the vehicles to customers on service contracts for about £500 per month - rather than selling them outright.
The cost is roughly the same as leasing and running a diesel Volkswagen Golf when fuel, insurance and other running costs are factored in, they say.
And the company will cover all repair, maintenance, insurance and fuel expenses.
However, a shortage of hydrogen filling stations – there are just 14 in Britain with 12 more set to open - means that much of the 300-mile range will be eaten up just getting to and from the 'gas' stations.
The Rasa uses a hi-tech fuel cell to generate electricity from hydrogen gas stored under pressure in a tank in the boot.
The hydrogen gas undergoes a catalytic reaction inside the fuel cell when it reacts with oxygen - a form of reverse electrolysis – to generate energy in the form of electricity and water, or H2O.
The electricity generated drives motors in each of the wheels and the water simply evaporates into the air, or dribbles onto the road.
Hugo Spowers, founder of the ecological car firm Riversimple insists hydrogen is actually safer than conventional petrol because it is contained in a pressurised tank.
Even if it did leak in a crash, the gas would dissipate upwards rather than 'pool' under the vehicle as is the case with unleaded.
'Every aspect of the Rasa has been tailor-made and interrogated for lightness, strength, affordability and safety, to produce a vehicle that will maximise hydrogen as a fuel source and minimise pollution,' explained Mr Spowers.
He noted: 'Customers will never actually buy the car and experience the burden of depreciation - they will simply exchange or return it at the end of the ownership period.'
Experts behind the scheme include former motor industry and aerospace engineers from the likes of Aston Martin and Formula 1 teams.
The futuristic Rasa has been styled by Chris Reitz, one of Europe's leading car designers behind the revamped Fiat 500.
Weighing in at just 580kg - or nearly half that of a small car – the Rasa features a carbon composite chassis and only 18 moving parts in the entire powertrain.
When the vehicle is in motion, hydrogen passes through the small 8.5 kW fuel cell of the size currently used in forklift trucks.
It combines with oxygen to form water and electricity to drive the motors positioned in each of the four wheels.
More than 50 per cent of the motion energy produced under braking is recovered and turned into electricity to boost acceleration.
Mr Spowers said: 'The result is a range of up to 300 miles on 1.5 kg of hydrogen, estimated fuel economy equivalent to 250 mpg, and a top speed of 60mph.'
The firm behind the car hopes the first production models, which are built at a boutique factory producing around 5,000 a year, will be on the road by 2018 and is seeking more backers.
Mr Spowers added: 'We really have started from a clean sheet of paper.
'The Rasa gives us the opportunity to introduce customers to a more convenient concept of motoring, a lightness of ownership that neither places a burden on the pockets of motorists or the surrounding environment.
'The car is simple, light and fun in every respect.'