See? And you thought all that praying to Ahura Mazda was for nothing, right? Well it worked: Mazda’s legendary Wankel rotary engine is coming back! To cars! Of course, Ahura Mazda’s power isn’t exactly what it was back in 500 BCE, so there’s a catch: the rotaries will just be used as range extenders for upcoming Mazda electric cars. Still, the rotary’s back! Finally, you can have apex seal problems on an electric car!
I kid, I kid! I love the rotary!
Mazda is planning to have 95 percent combustion-electric hybrid vehicles by 2030 (the remaining 5 percent will be be pure battery-electric vehicles), and are planning to use rotaries as range extenders for the hybrid vehicles, citing the rotary’s small size to power output ratio, quiet operation, and fuel flexibility:
The rotary engine’s small size and high power output make multiple electrification technology solutions possible via a shared packaging layout. Taking advantage of the rotary engine’s compatibility with gaseous fuels, the rotary-powered range extender is designed to also burn liquefied petroleum gas and provide a source of electricity in emergencies.
A rotary is a pretty good choice for a range-extending engine for not just the reasons cited above, but because it’s pretty much vibration-free and has fewer moving parts than a conventional piston engine, helping with maintenance and longevity.
It’s possible the rotaries used may be small and oriented with the rotor on a horizontal plane rather than a vertical, as seen in this Japanese patent drawing from September:
A flat, horizontal layout will likely make packaging easier, possibly allowing a rotary range extender to be housed in an underfloor compartment along with a hybrid’s batteries.
The first Mazda hybrid with a rotary range extender is expected to come out in 2020. Sure, it’s not an all-new rotary RX-7, but I’m just happy to see the rotary engine still staying alive and relevant.