The Optima Hybrid employs a Kia-developed powertrain that includes several innovations, such as advanced lithium polymer batteries that Kia says won’t need replacing for up to 10 years or 240,000kms.
It makes use of a ‘full parallel hybrid system’, where the 2.4-litre GDi direct injection petrol engine is mated to a small electric motor and drives the front wheels via a six-speed automatic transmission – without the traditional torque converter.
A special clutch is fitted between the engine and motor, enabling the petrol engine to be de-coupled from the powertrain so that Optima can be operated in zero-emission, full-electric drive mode from standstill up to 100km/h (reached in 9.2 seconds) or in blended electric-petrol mode at any speed. If the electrical load is low when the car comes to a stop, the engine shuts off to eliminate idle fuel consumption and emissions. Together, the 2.4-litre petrol engine and 40kW electric motor produce a combined power output of 154kW and 265Nm of torque and when it’s running on electric alone produces no emissions.
Overall combined emissions are estimated to be 99 grams of CO²/km.
Kia says the system’s configuration does not require a high-capacity electric motor and generator, therefore saving weight and cost. The lower weight, coupled with the hybrid drive and the Optima’s low CD 0.26 aerodynamic shape, all help to improve the new model’s fuel economy by 40.7% to 6.2L/100km in the combined cycle. This is aided by lowering the car 5mm and including an ‘active air flap’ in the front grille, smooth under-floor panels, low-drag wheels and low rolling resistance tyres.
Currently the Optima Hybrid is only available in left-hand-drive, but if it does become available to right-hand-drive markets, Kia Motors New Zealand General Manager Todd McDonald says he would be very interested in considering it for this country.
“It’s a very advanced hybrid car, yet simpler and less complicated than some that we have seen come onto the market,” he says. “Compared with nickel-metal hydride batteries used in some other hybrids, lithium polymer batteries weigh 20-to-30% less, occupy 40% less volume and are 10% more efficient. They also hold their charge for 25% longer than nickel-metal hydride batteries and that’s one reason why they have such a long lifespan.”