Kia already has hybrid, electric and plug-in hybrid models on sale in the UK.
The new EcoDynamics+ engine will feature in the Kia Sportage when it debuts, then later in the third-generation Ceed in 2019.
Kia is introducing EcoDynamics+ 48V mild-hybrid diesel engines to their United Kingdom range later this year in a bid to reduce emissions.
Compact packaging means the system easily integrates into existing architecture.
Sportage will be the first model to offer the new EcoDynamics+ powertrain later in 2018.
The technology includes a compact 48-volt battery under the boot floor, charged using energy recuperated through a motor-generator connected to the engine's crankshaft.
Kia says the system can switch between two modes, called "motor" and "generator".
While some automakers have started ditching oil burners completely, others, such as Kia, continue to invest in new technology that helps diesels improve fuel economy and emit less CO2.
The battery recovers energy from the diesel engine's crankshaft when the auto is decelerating or driving downhill.
Full prices and specs for vehicles fitted with the new powertrain are yet to be confirmed. It can even deliver a "Moving Stop-Start" if there's enough charge in the battery. This allows the internal combustion engine to automatically turn off during braking and in-gear deceleration, whereas the MHSG can re-ignite it whenever the driver presses the throttle.
Additionally, a DC/DC converter enables the 48 volt battery to connect to the vehicle's on-board power supply, leading to a significant reduction in the size of the 12 volt battery required to power the car's ancillary electronics. The adoption of the MHSG also means the conventional starter motor can be downsized and used primarily for cold starts at low temperatures.
The diesel mild-hybrid powertrain is compatible with both manual and automatic transmissions, and could be adapted for front-, rear- and all-wheel drivetrain layouts.
Kia will announce more detailed plans for the roll-out of its new mild-hybrid technology later this year.