Given the packaging and power density and NHV advantages of a Wankel, it is an obvious choice for this application. Presumably it spins at a constant speed and therefore it fatal flaws are manageable. Emissions, seal life and efficiency I think were the problems.
No surprise Audi used it because Audi bought NSU way back and NSU was the first car company to bet the farm on Wankels. Lost the farm as Mazda almost did.
However, the NSU Ro-80 may have been the most advanced production car on the planet in its day.
This A1 looks as though it is taking the Volt approach and it makes a lot of sense if you can come up with and ICE which perfectly suits the application. I'd say the Wankel is better than a conventional piston engine if its weaknesses have been controlled.
Cheers,
John M.
