Described by BMW as the first hydrogen-powered luxury saloon, the BMW Hydrogen 7 was based on the regular 7 Series and had a 12-cylinder engine that could run on both petrol and hydrogen.
Just 100 examples of the model were built in 2007, but all had to meet the standards demanded of any production BMW.
The car was set up to run primarily on hydrogen, and thanks to a tank that would hold 8kg of fuel, it had a range of more than 125 miles on top of its 300-mile range on petrol.
The driver could switch between the two fuels simply by pressing a switch on the steering wheel, and there was no discernible difference between the cars performance on the two fuels. It could hit 60mph in just 9.5 seconds.