The Suzuki Vitara, Swift Sport and S-Cross will gain a new 48-volt mild-hybrid powertrain in the spring of 2020, and a new K14D Boosterjet petrol engine.

Replacing the current 1.4-litre Boosterjet in models with manual transmission, the new system is said to achieve a CO2 emissions reduction of up to 20% with a 15% improvement in WLTP fuel economy.

The system consists of a 48V lithium-ion battery mounted under the front seats, charged by a belt-driven integrated starter generator (ISG).

The ISG recovers energy that would otherwise have been lost during braking and deceleration, but can also assist the petrol engine during acceleration, leading to a combined torque output of 235Nm from 2,000rpm.

Using a 48V/12V converter, energy recovered in this way can also power the vehicle’s electrical systems, while the ISG can quickly and quietly restart the engine after stop/start activation.

The system also offers an electric idle function that uses the motor to keep the engine spinning at a low rpm when the clutch is disengaged, effectively saving the fuel that would have otherwise been used to do so.

The system adds only 15kg to the vehicle’s overall weight.

Further details are due to be announced before the anticipated March 2020 launch.