Why Mazdas of the future will still have rotary engines

Mazda’s last rotary engine, the Renesis, from the RX-8

Mazda’s R&D chief, Hidetoshi Kudo says a hybrid with a main rotary engine is a possibility, and explains why the MX-30 EV is right-sized for Singapore


Tokyo, Japan 

Mazda has debuted its first battery electric vehicle (BEV), but that doesn’t mean it’s going all-in on electric cars just yet. While its stated goals for carbon dioxide (CO2) reduction include a 50 percent cut by 2030, and 90 percent by 2050, it believes there’s plenty of life left in internal combustion engines (ICE).

READ MORE: CarBuyer was on the scene as Mazda unveiled its first BEV, the MX-30, at the Tokyo Motorshow 

Like other carmakers, Mazda’s answer is that only a spectrum of electrification and combustion tech can meet the varied power types, laws, and automobile infrastructures around the world. 

BEVs are the headliners of a greener motoring movement, but Mazda believes they will still be a small piece of the overall green puzzle in the near future: By its prediction, even in 2035, only 11 percent of new cars will be BEVs – but 84 percent of cars sold will still be using ICEs (internal combustion engines) in the form of hybrids. 

“Mazda’s approach to environmental conservation doesn’t just look at structural requirements, but we see multiple solutions that help meet the functional requirements – reducing CO2 and exhaust emissions,” says Hidetoshi Kudo, Mazda’s executive officer in charge of R&D administration, product strategy, and the Mazda Technical Research Center.

Mr Kudo (shown above in a CarBuyer file photo) was speaking at a presentation on Mazda’s environmental and electrification strategies at the company’s Tokyo office, which CarBuyer attended.

READ MORE: Skyactiv X – CarBuyer has tested Mazda’s holy grail of combsution engine technology in full-production guise

In other words, what helps reduce emissions right now is what works best – which is why the brand has continued its efforts in improving the efficiency of ICEs, the most significant example being its Skyactiv X homogeneous charge/compression ignition technology. 

Mr Kudo also revealed additional details that illuminate Mazda’s choice of a smaller battery pack (35.5kWh) for its MX-30 BEV (shown below).

From a total emissions perspective – i.e. well to wheel or the whole life cycle of the car – a 35.5kWh battery EV already emits more CO2 than a Mazda 3 diesel when it rolls off the factory line, though it emits less by the end of its lifetime. 

However, a BEV with a larger 95kWh battery would create significantly more emissions than a Mazda 3 diesel through its entire lifecycle, given the same circumstances.

He also revealed data that is of particular interest to potential MX-30 owners in Singapore: When factoring in the power used to supply EVs, coal (the worst fossil fuel) resulted in more CO2 life-cycle emissions by far, while natural gas (which is what Singapore uses) saw roughly the same total CO2 emissions as a Mazda 3 diesel. Solar energy, as expected, saw significantly less total CO2 emissions.

The future of Mazda’s powertrains wouldn’t be fitting without the usual Mazda ‘renegade’ touch, and here Mr Kudo revealed the first details into Mazda’s forthcoming range of hybrids. 

Mazda’s signature rotary engine technology will play a big part in the coming days. The rotary range extender from the MX-30 can be scaled up or down to suit a plug-in hybrid, or even a series hybrid (like Nissan’s e-Power), and it’s even multi-fuel capable – so it could even build a rotary engine that runs on hydrogen. 

READ MORE: Toyota’s banking big on hydrogen with its second-generation Mirai fuel-cell vehicle 

That leads to tantalising possibilities for long-time fans of Mazda’s rotary engines. But what about a Mazda car where the rotary engine is the prime mover of a parallel hybrid system? 

“Yes,” he said with a smile, “That is certainly a possibility.” 

Mazda’s next wave of new-gen vehicles will include hybrids of all sorts – from plug-ins, to parallel hybrids and possibly series hybrids. The new Mazda 3 is the first step here, with it debuting a mild hybrid system. 

Fans will expect a rotary engine to return in a spiritual successor to the RX coupes, and Mazda has already shown the RX Vision and Vision Coupe concepts as examples of what it could look like. 

However, it’s also revealed plans for an inline-six engine and longitudinal rear-wheel drive platform – all hallmarks of a luxury car – so we can’t say for certain what the next Mazda sports car, if it exists, will be powered by.

In any case, it’s a question we’ve literally asked Mr Kudo before – see point five of this story. 

But rotary going returning to a mainstream car wouldn’t be out of place either, and more relevant to Singapore: Imagine a hybrid Mazda 3-sized car with a main rotary powerplant.

That might be able to pull off the hardest trick of all, by appealing to both car enthusiasts and future-minded drivers at the same time.

about the author

Derryn Wong
CarBuyer's chief editor has a keen interest in all things mechanical, technological, animal and mineral. He's particularly fascinated by eco-cars and cars which make no logical sense. An avid motorcyclist and photographer, he also enjoys cats.