Mazda To Use Rotary Engine As Generator In Hybrid Models From 2022

The final Mazda RX-8 and its 235 hp rotary engine ended its production back in 2012. After a ten-year absence, Mazda is bringing back the smooth-spinning rotary engine, but as a form of a hybrid powertrain next year. 

Mazda has disclosed the 2022 timeline at a recent shareholders meeting on the company’s progress to electrification and new technologies.

Although details are scarce, it is believed that Mazda will use a rotary engine as a range extender with the MX-30 crossover being the first model. Benefits of a rotary engine include low vibrations, compact size and lightweight.

A range extender setup basically adds an on-board generator onto a fully electric powertrain to charge the battery pack for an additional range. For the application in the future Mazda, the petrol-powered rotary engine spinning at a constant revolution will be the on-board generator.

Being specifically designed for a constant spinning speed means all the negativity associated with the rotary engine such as high fuel and oil consumption can be minimized. 

The rotary engine is not expected to drive the wheels; a task still performed by the electric motor with its simple one-speed gearbox. Nissan has a similar setup with its ‘e-power’ hybrid setup, where a 1.2-litre three-cylinder engine act as the generator to charge its lithium-ion batteries.

Nissan’s approach is more petrol-biased, as the battery pack only has 2 kWh energy content. Owners of ‘e-POWER’ vehicles still pump a reasonable amount of petrol like other self-charging hybrids. 

The current range of the fully electric MX-30 is 200 kilometres from its relatively small 35.5 kWh battery pack. Mazda says the battery sizing is a balance of environmental impact as well as meeting the practical daily needs of users. 

With the range extender, the total driving range will probably increase by 50%, making it more competitive among the mass-market electric vehicles.