We've loved the concept of the Audi A1 e-Tron concept since its launch at the 2010 Geneva Motor Show last March.

It's a range-extended electric vehicle (like the 2011 Chevy Volt) that uses a tiny Wankel rotary engine to run a generator that produces electricity to power the car once its lithium-ion battery is depleted.

But now reports out of Germany says that Volkswagen, Audi's parent company, is not so pleased.

Volkswagen Golf Blue e-Motion

Volkswagen Golf Blue e-Motion

Volkswagen has its own schedule of electric cars on the way, including the 2013 Golf Blue E-motion, an electric conversion of its next-generation Golf compact hatchback.

Not unreasonably, VW thinks the group's electric cars should share common technology--and a rotary range extender is definitely not in the master plan.

Audi denies any conflict, despite a translated quote from the Financial Times Deutschland that has VW calling its plans to produce the A1 e-tron 'anarchic'.

The first production rotary car in the world was built and sold by NSU, a German car company later rolled into what is now Audi. Given BMW's plans for its MegaCity electric urban car with a carbon fiber body, Audi apparently sees a rotary engine as a way to compete and distinguish itself technologically.

It promises to be a fascinating vehicle, this littlest of the e-tron range, and we hope that Munich road testing due to begin later this year prove the concept's viability.

Of course, the electric cars from Volkswagen and Audi already share at least one thing: odd names. It's hard to imagine visiting your VW dealer to ask for a Blue Emotion.

As for e-tron, well, the French will tell you it means something not very pleasant.

[Automotive News (subscription required)]