Mazda's rotary range extender on hold

TOKYO — Mazda's plans to resurrect its trademark rotary engine as a part of an electrified range extender are now on the back burner.

The rotary range extender had been expected next year as part of the company's multiple-solution approach to electrification. Mazda Motor Corp. still plans to resurrect the rotary — but first as a power-assist technology for series and plug-in hybrid offerings.

"We are still considering using rotary engine as a range extender, but the timing of its introduction is undecided," spokesman Masahiro Sakata said.

Mazda's commitment, however, may be shaky. Japanese media reports say Mazda has scrapped plans for using the rotary range extender in the MX-30. Mazda ditched the rotary range extender partly because it required a bigger battery that would make the vehicle too expensive, Japan's Nikkei business daily and Nikkan Jidosha Shimbun reported.

Mazda declined to comment. The rotary range-extender version of the MX-30 was slated to debut globally in the first half of 2022, with an eye to the U.S. and Europe.

The MX-30 is designed to accommodate a range of drivetrains. It was introduced last year as a full electric variant that was the company's first mass-produced EV. The EV was launched in Europe, while Japan got the EV alongside a mild hybrid version.

The all-electric MX-30 for Europe and Japan uses a relatively small 35.5-kWh lithium ion battery and 105-kW electric motor. In Europe, its range is rated at 124 miles on the WLTP standard, which often generates higher estimates than the EPA test.

A plug-in hybrid version would allow Mazda to further reduce the size and cost of the battery, compared with that in a range extender. But the engine would operate more frequently.

The plug-in battery is expected to be around 10 kWh, the Nikkei said.

Mazda confirmed that the rotary plug-in and series hybrids will be introduced between 2022 and 2025. The engines will act as generators and not directly power the wheels mechanically.

As recently as last month, Mazda pitched the rotary engine as an optimal match for an electrified drivetrain in regions where there is a clean power source and a suitable recharging network.

The range-extender setup, Mazda said, would use a small engine, a big battery and a small fuel tank.