It’s no secret that BMW’s long-term aim is to make hydrogen technology work, but it seems the company can’t make the leap in one move. ‘There are three stages to BMW’s work,’ an insider told us. ‘Right now we have Efficient Dynamics. That will develop into “mild” and “full” hybrids before we reach hydrogen.’

Alongside this, BMW also has ‘Project i’, established to research and develop city cars. Plant Oxford is currently building several hundred engineless Minis, which are being shipped to Munich to have electric internals fitted for worldwide trials.

Exactly what technology these cars will contain is a closely guarded secret, but our source said they won’t feature lithium-ion batteries like the Tesla, nor in-wheel motors like the Lightning. ‘We’ve been doing trials for the past nine years and haven’t got either to work satisfactorily,’ we were told.