01:05 21-09-2025

Subaru's turbine range extender could redefine hybrid EREV design

Subaru has patented a system that swaps the usual piston engine in a hybrid for a turbine that works as a generator. In extended-range mode (EREV), the turbine would charge the battery, allowing a more compact and lighter setup than a traditional engine.

The company has relevant experience to lean on: through its aviation division, Subaru has taken part in the production of trainer aircraft and helicopters, including licensed versions of Apache and Bell models. Now its engineers want to translate that expertise to road cars.

Turbines offer strong power-to-weight, a simple design, and long service life. With careful calibration, they can even emit fewer pollutants than Subaru’s conventional engines. The drawbacks are familiar—noise, hot exhaust, and slow start-up. In the new patent, the team proposes using the generator not only to charge the battery but also to spin the turbine up quickly, shortening start times and cutting noise.

The setup includes two batteries: a high-voltage main pack and an auxiliary 12-volt unit that can start the turbine even when the main battery is low. The result should be less frequent turbine operation, but larger energy top-ups per cycle.

Experts are already comparing Subaru’s idea with Mazda’s approach, where a rotary engine serves as a generator for hybrids. If this technology reaches production, the market could get a distinctly new kind of hybrid. The concept reads as smart packaging for everyday use—especially if the promised quick spool-up and quieter operation hold true.