Toyota is reportedly considering a hydrogen internal combustion engine for the next-generation Prius, as part of its plug-in hybrid powertrain.

A few weeks ago, Forbes reported that Toyota is getting ready to unveil the fifth-generation Prius in late 2022. This one will likely be a gas-electric hybrid but a second variant allegedly coming in 2023 is rumored to combine a hydrogen internal combustion engine with electric motors. A more recent report by Best Car Web also talks about a hydrogen-powered Prius PHEV but it claims it won’t appear in production form before 2025.

Read Also: Toyota Keeping Its Options Open, Won’t Commit To An EV-Only Future

Unlike hydrogen fuel cell powertrains like the one used on the Toyota Mirai, converting an internal combustion engine from gasoline to hydrogen is far less complex – even if it is combined with a battery and a couple of electric motors. The new technology – still at an early stage of development – was tested in a modified Corolla on a 24-hour race last June, and while the car spent a lot of time in the pitlane for various issues, it did manage to finish the race.

The prototype motor was based on the turbocharged 1.6-liter three-cylinder engine found on the Toyota GR Yaris with a series of modifications allowing it to use compressed hydrogen as fuel, and the addition of four carbon-fiber hydrogen tanks located at the rear. Toyota says that the engine is more responsive since hydrogen combustion occurs at a faster rate than gasoline. Thus, the car retains most of the characteristics of ICE-powered cars but it does without any CO2 emissions (it only emits NOx due to the oil).

Since it arrived in 1997, the Toyota Prius was a pioneer in hybrid technology. However, now that fully electric vehicles are becoming the new norm, it has to find another way to distinguish itself in the crowded market while retaining its eco-friendly character.

During the past years, Toyota is trying hard to find a new role for the Prius in its electrified lineup. Sales of the once-popular model have been declining, and it seems that having an efficient hybrid powertrain and an aerodynamically shaped body is not enough to attract new buyers. At the same time, a fully electric or a fuel-cell Prius wouldn’t make any sense since Toyota wants to keep it affordable. And this is when a hydrogen-burning motor steps in as a great alternative to fully electric powertrains.

By giving the forthcoming fifth-generation Prius a hydrogen-burning engine and retaining the electric motors, Toyota might have found a genius way to continue its legacy. After all, it will still be a hybrid while significantly improving its efficiency and environmentally friendly credentials. The only important issue here is to improve hydrogen infrastructure so drivers can refuel in more places.