Return of the Wankel: Mazda's 2020 Rotary Engine

Eight years ago, Mazda let the Wankel rotary engine production lapse when they canceled the RX8 sports car. In 2016, Masamichi Kogai- the CEO- shut down rumors of an RX9 rotary sports car possibly hitting the market, though his verbiage left the door open to future use of the rotary engine in other ways.

Vehicle enthusiasts the world over are chomping at the bit for a look at the new plug-in hybrid vehicle- which features a rotary-style engine as a range-extending generator. Paired with an electric motor, the rotary-powered generator will provide power for the vehicle if and when the battery is drained.

What is a Wankel?

Along with an electric motor and a plug-in battery pack, range-extended electric vehicles also come equipped with an internal combustion engine. Though similar, the main difference between this and a plug-in hybrid is its use of the internal combustion engine, which acts as a generator to recharge the battery when it has become depleted, and the electric motor will drive the wheels. So, what is a rotary-style engine?

Far from a conventional piston engine, a rotary-type is an internal combustion engine that is barrel-shaped, with triangular rotors, rather than pumping pistons. These rotors (anywhere from 1-3, usually 2) spin around inside a shaft located inside the hollow barrel. When air and fuel are pushed into the free spaces inside, they ignite, causing the exploding gases to turn the rotors.

These triangular rotors are doing the same job as the pistons when they move up and down. The advantage with a range-extended engine is thanks to the need for fewer parts. This cuts back on replacements and repair costs and delivers a much lighter alternative engine.

In the 1920s, Felix Wankel, a German engineer, came up with his concept of a rotary-style engine. However, due to his decision to take part in the Nazi's WWII rhetoric, he was unable to develop a prototype until 1951. It's interesting to note, though it's referred to as the 'Wankel' rotary engine, in truth, much of its design actually comes from Hanns Dieter Paschke, a fellow NSU engineer. He took Wankel original concept and delivered a simpler version, which was then adopted by Mazda.

Pistons of the Past...

All hybrids in production to date, use repurposed piston generators. Piston generators being bulky and weighty, the use of a rotary range-extending generator in their newest vehicle is as innovative as it is prudent. The type of car the Wankel rotary range-extending generator has yet to be announced, though they have stated there will also be 100% electric version offered as well.

Having been created to run on gasoline or liquefied petroleum gas, this model will offer electricity to external power sources and appliances in the event of an electrical outage. The new rotary range-extending generator will produce a vehicle that is inherently quiet, with a small, lightweight design.

Still Waiting

By 2030, the company hopes to have 'electrified' up to 95% of its vehicles. In 1967, they were one of the very first automakers of their kind to produce a rotary-powered engine. They were also one of the last ones selling these older models. The RX8 went out of production in 2011, due to its poor emissions and fuel economy- two issues which have been addressed with their new rotary range-extending generator paired with the electric motor.

Though the newest model won't come out until 2020, and we're still not even sure in what sort of vehicle the range-extending engine will be featured, the excitement surrounding the electric drivetrain's companion is undeniable. The innovative engine designs from Mazda have been thrilling and exciting car lovers for decades. This one will surely be no different.

The pros and cons of a rotary vs piston-powered engine will differ from vehicle to vehicle and driver to driver. Each may see a different aspect in a different light and, therefore a 'pro' for one may become a 'con' for another. Regardless of where you stand- whether you're a die-hard piston pioneer or a righteous rotary representative, its clear and certain the innovations made with rotary-style engines are incredibly intelligent in design and efficiency.

The community at large is waiting for the release of more information and a first, closer look at how the rotary range-extending generator will come into play with future vehicle productions. Is this the beginning of a new era in auto manufacturing? Will we see a drastic decline in piston engine production as the supply and demand trends change in this ever-evolving industry? Perhaps. Perhaps not.

Piston-driven engines are still immensely popular and effective for many drivers. The rotary range-extending generator may not be the catalyst for futuristic change some have been hoping for. But, it is a step in the right direction and has continued to excite drivers and engineers alike.