BMW is abandoning its work on hydrogen-powered internal combustion engines, admitting that the technology has run its course.
Despite rumours that the Bavarians were getting out of new fuel altogether, the company has confirmed that its future efforts with hydrogen will be focused on fuel cells and improving storage systems like cryogenic reservoirs.
BMW and Mazda have been the only two mainstream manufacturers to seriously pursue internal combustion hydrogen technology, with most others preferring to use it to supply a fuel cell and produce electricity.
The main advantages are cleaner running and the continuation of the internal combustion engine, a piece of machinery that you could say has had considerable investment poured into it over the past 150 years.
But the negatives proved too much for BMW in the end.
The tank in the Hydrogen 7 chilled the gas to a liquid at -253 degrees (rather than compressing it to around 800 bar as others have done), a process that takes around a third of the energy in the tank to achieve.
The hydrogen was also rather unstable in the onboard storage and evaporated from full to empty within three weeks.
Fuel efficiency was also a worry, returning figures of 29.4 litres/100km and taking the car no more than 200km.
BMW says it will continue to service the 100 7 Series-based Hydrogen 7s it developed, but future advancements to internal combustion hydrogen units appear as good as dead.