Volvo, together with the unveiling of the refreshed XC90 SUV, has released its new line of upgraded and newly-developed electrified engines that will be available across the entire model range.

First of all, the Swedish automaker’s existing T8 and T6 Twin Engine plug-in hybrid powertrains have all been upgraded with new batteries and brake-by-wire energy recovery system. Volvo claims both the T8 and T6 PHEV systems (the former now makes 420 hp) boast an increase of 15% in driving range.

At the same time, Volvo has also confirmed that all models will be available with a plug-in hybrid option in the near future. That includes cars underpinned by the Scalable Product Architecture (SPA) and the smaller Compact Modular Architecture which the XC40 rides on. Currently, the CMA platform features a T5 Twin Engine plug-in hybrid option, but a T4 Twin Engine option will be introduced at a later date.

In the coming months, Volvo will begin rolling out mild hybrid petrol and diesel powertrains for the XC90 and XC60. This system comes with Volvo’s advanced kinetic energy recovery braking system, which is coupled with its existing internal combustion engines to create a new integrated electrified powertrain. All mild hybrid Volvo models will get the new ‘B’ badge.

This new mild hybrid powertrain, electrified via energy recovery, offers drivers up to 15% fuel savings and emission reductions in real world driving. The new brake-by-wire system works in tandem with the energy recovery system and reduces fuel consumption and emissions by recovering kinetic energy under braking.

The refreshed XC90 will soon be available with the B5-badged petrol/diesel mild hybrid, as well as a B6-badged petrol mild hybrid model. The same B5 and B6 offerings will be extended to the XC60, though the smaller SUV will be joined by a B4 diesel mild hybrid.

Volvo also notes that B5-powered models will be available with front-wheel drive or all-wheel drive. For now, the carmaker has released technical specifications of the diesel B5 AWD powertrain for the XC90, which features a 2.0 litre four-cylinder turbodiesel (twin turbo) providing 235 PS at 4,000 rpm and 480 Nm of torque from 1,750 to 2,250 rpm.

The mill is mated to an AWF8G55 eight-speed automatic, and is good for a century sprint time of 7.6 seconds; 220 km/h top speed. Meanwhile, the electric motor provides an additional 14 PS and 40 Nm to the driveline when needed.

Volvo has been developing its version of kinetic energy recovery system (KERS) since 2011, and it differs from the belt-driven starter-generator setup used in other mild hybrids, whereby regenerative braking is used to charge the drive battery.

In previous prototypes, Volvo’s KERS is fitted to the rear axle and is based on a carbon-fibre flywheel. Upon braking, energy is transferred through a brake-by-wire recovery system to the flywheel, which quickly spins itself up to 60,000 rpm. When the car starts moving off again, the flywheel’s rotation is transferred to the rear wheels via a specially designed transmission, providing a boost of up to 80 hp.