Before the Plug-in Hybrid is available, the Hybrid Optima will go on sale. Compared to the current model, it will feature significant improvements. The Hybrid will feature a larger battery, a more powerful electric motor and a revamped transmission system, targeting 10% greater fuel economy.

Coupled with a six-speed automatic transmission, the core of the innovative powertrain is Kia's 2.0-litre 'Nu' four-cylinder GDI (gasoline direct injection) engine, expected to generate 156 ps and 189 Nm. The engine is aided by the 38 kW electric motor. Backing up the engine, transmission and motor is an upgraded lithium-polymer battery pack, with a capacity of 1.62 kWh – an increase of 13%, which is totally hidden underneath the boot floor.

The next-generation Optima PHEV will be fitted with a 9.8 kWh lithium-polymer battery back (roughly six times the energy output of that found in the current-generation Optima Hybrid) and a 50 kW electric motor. This will allow the Optima PHEV to operate in pure-electric mode at higher speeds than Optima Hybrid and will be able to drive in all-electric mode for up to 44 kilometers, placing the Optima PHEV among the leaders in the D-segment for pure-electric range.

In the core of the new Optima PHEW powertrain there will is a 156-horsepower 2.0-litre 'Nu' GDI engine, paired with an 38 kW electric motor with a six-speed automatic transmission. The upgraded transmission also features a clutch to replace the traditional torque converter. The PHEV will recharge in less than three hours at a 240V Level 2 charging station, or nine hours from a standard 120V power outlet.

In the future, Kia has big plans with hybrid, plug-in hybrid and electric cars. In the next five years, Kia plans to expand its current green car line-up from the four current models to 11, and is targeting a 25% improvement to average corporate fuel efficiency over 2014 levels.