The all-new Optima Hybrid saloon makes its European debut at the Geneva Motor Show, raising Kia’s environmental credentials to a new level.

Taking Kia forward into its ‘EcoDynamics’ era, the Optima Hybrid, first shown at the Los Angeles Auto Show last November,  is another major step towards the company’s goal of manufacturing and marketing environmentally-friendly personal transport for future generations.

A product of Kia’s Eco-Technology Research Institute near Seoul, together with the Namyang Research and Development facility the Optima Hybrid is a unique collaboration between numerous Kia facilities around the world.

The ‘full parallel hybrid system’ created for the Optima Hybrid will be further developed for use in forthcoming Kia models during the next decade.

Scheduled to begin mass production in September 2011, the Optima Hybrid employs a truly innovative Kia-developed hybrid powertrain that delivers a unique blend of performance – acceleration to 62 mph (100 kph) in 9.2 seconds and a top speed of 121 mph (195 kph) – plus class-leading fuel economy, achieving a 40.7% fuel consumption improvement compared with the standard US petrol version.

The Kia Optima Hybrid is equipped with an ingenious, simple and cost-effective ‘parallel hybrid system’.  The 2.4-litre petrol engine is paired with 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 Optima Hybrid’s petrol engine and the electric motor, enabling the petrol engine to be de-coupled from the powertrain so the sleek saloon can be operated in zero-emissions, full-electric drive mode from standstill up to 62 mph.  Furthermore, the system’s configuration does not require a high-capacity electric motor and generator, saving both weight and cost.

Seamless driving for everyday motoring

When setting off, the Optima Hybrid operates in Electric Mode.  As vehicle speed increases, the Hybrid Starter motor/Generator (HSG) starts the petrol engine and the clutch is closed, allowing the engine to take over the task of powering the car.  The electric motor switches into hybrid operation and serves as either a secondary engine (during full acceleration and hill-climbing) or a generator (during cruising and deceleration) to recharge the battery pack as necessary.  Whenever the car comes to a stop for more than a few seconds, the petrol engine automatically shuts off to conserve fuel and minimise emissions.

When braking, the electric motor converts kinetic energy into electricity for storage in the battery pack.  The 8.5 kW HSG also functions as a generator to re-charge the battery pack if the state of charge is low when the car is stationary.  Throughout the entire driving experience, in everyday motoring, under all conditions, the hybrid operation is automatic and seamless.

A responsive and rewarding drive is guaranteed by the Optima Hybrid’s 30kW Interior Permanent Magnet (IPM) synchronous electric motor, which produces 40.7 ps and 205 Nm of torque from 0-to-1,400 rpm in electric mode, and the combined (electric motor plus gasoline engine) hybrid powertrain output of 209 ps and 265 Nm of torque.

State-of-the-art batteries & optimised engine

Kia’s Optima Hybrid employs a lithium polymer battery array developed in partnership with LG Chem.  Lithium polymer is ideal for automotive applications and these new batteries provide an optimum balance between power delivery, energy density and thermal stability.  Reliability is so good that the Optima’s battery pack will not need replacing during the vehicle’s lifespan – at least 10 years and 150,000 miles.

Taking advantage of the additional, instant and continuously available torque from the electric motor, Kia has modified its popular four cylinder 2.4-litre Theta II engine to maximise its efficiency and achieve a 10% fuel saving over a regular Theta engine.

For the Optima Hybrid, Kia has modified the six-speed automatic transmission found on the conventional Optima for hybrid application.  The traditional torque converter is replaced with the electric motor and a high-efficiency oil pump.  This allows EV mode operation, maximises regeneration of kinetic energy during braking and also provides a more responsive drive than competitors’ CVT systems.

Engines

2.4-litre
Fuel typePetrol
Displacementcc2,359
Power outputps209 @6000 rpm
Torque outputNm265 @ 4200 rpm
Bore x Stoke88 x 97 mm
Compression ratio13.0:1
ConstructionAluminium cylinder block and head
Electric motor30kW electric motor powered by long-life 270V lithium polymer battery pack
Engine detailsTheta II, In-line four cylinder with 30kW parallel electric motor

Transmission

Transmission typeSix-speed auto
Gear ratios 1st4.212
2nd2.637
3rd1.800
4th1.386
5th1.000
6th0.772
Reverse3.385
Final drive3.320

Suspension, steering and braking

Front axleFully independent subframe-mounted MacPherson struts with coil spring and twin-tube gas-filled shock absorbers and 24 mm anti-roll stabiliser bar.
Rear axleFully independent subframe-mounted multi-links, coil springs and twin-tube gas-filled shock absorbers. Standard ASD shock absorbers. 15mm diameter anti-roll stabiliser bar.
Braking systemVentilated front discs 300 x 28 mm, and solid rear discs  284mm x 10mm 4-channel anti-lock system with EBD and BAS
SteeringMDPS electric power-assisted, rack-and-pinion, 2.9 turns  lock-lock
Wheels16 in x 6.5j / 17 in x 6.5 j
Tyres205/65 R16 tyres / 215/55 R17 tyres

Dimensions and weights

Wheelbasemm2,795
Overall    l / w / hmm4,845 / 1,830 / 1,450
Front / Rear overhangmm965 / 1,085
Front / Rear trackmm1,601 / 1,601
Head / Leg / Shoulder room frontmm1,015 / 1,115 / 1,455
Head / Leg / Shoulder room rearmm955 / 880 / 1,415
Turning circlemetres10.4

Performance and fuel consumption

2.4-litre
Petrol
Acceleration (0-100 kph)*seconds9.2
Maximum speed*kph195
Fuel consumption**mpg37
Fuel tank capacitylitres65

* Figures stated are manufacturer’s estimates

** Consumption figures are based on US EPA official cycle (US gallons)