Set to be unveiled at the Paris Motor Show later this week, the Kia Optima T-Hybrid concept previews a future diesel-electric hybrid version of the Korean D-segment sedan. More than that, it’s the first showcase of the brand’s new “mild hybrid” powertrain that could be applied to future Kia models.

The Optima T-Hybrid (for turbo-hybrid) uses the standard (Europe-only) 1.7 litre CRDi turbodiesel engine as its main source of power, but here it’s paired to a small electric motor and a 48 V lead-carbon battery. The latter is chosen over a lithium-ion unit as it requires no active cooling. It’s also easier to recycle at the end of its lifecycle.

For an extra boost of power, there’s an electric supercharger linked to the engine (on top of the mechanical turbocharger) for improved torque and engine response at low engine speeds. That is if the engine is on, of course, as the Optima T-Hybrid has a zero-emissions electric-only mode at low speeds and cruising conditions.

Also in the mix is Kia’s new automatic stop/start system with a belt-driven starter generator in place of a conventional alternator, which allows for quick restarts with minimal noise and vibration. The fitment of a smaller battery and starter motor also enhances weight distribution and handling.

Power and efficiency figures have yet to be confirmed, but Kia targets a significant reduction in fuel consumption and CO2 emissions, as well a 15-20% increase in power with the use of this mild hybrid system. The application of this technology is not limited to the Optima alone, of course.

Plans for full mass production (Optima T-Hybrid or other possible models) are still up in the air, but you wouldn’t bet against Kia making it a reality, would you?