It's billed as the world's first dedicated luxury hybrid vehicle. Behold the Lexus HS 250h.

Equipped with Lexus' first four-cylinder petrol engine, the 2.4-litre Atkinson-cycle powerplant is part of the latest Lexus Hybrid Drive System, which generates 187 total system horsepower. Expected fuel efficiency will be more than 30 percent better than the most fuel-efficient model currently in the Lexus lineup.

Like the all-new 2010 RX 450h hybrid utility vehicle that made its debut in November, the HS 250h will include a new system designed to improve efficiency.

The exhaust heat recovery system reduces engine warm-up time, allowing it to stop earlier, more often, and for longer periods. A windshield with infrared-ray reduction properties, which helps keep the interior more cool, has been adopted in order to decrease the amount of air conditioning needed to lower the cabin temperature. And aerodynamic work has reduced the drag coefficient to a low 0.27.

In keeping with the energy conservation theme, HS 250h includes plant-based, carbon-neutral "Ecological Plastics" or bio-plastics in specific interior areas. Ecological Plastic emits less carbon dioxide during a product's lifecycle than plastic made solely from petroleum.

The HS is slightly longer and taller than the IS, with contoured front-seat backs adding to increased rear-seat legroom.

Of course, all the typical Lexus modcons ? from Heads Up Display to "Enform and Safety Connect" telematics systems ? are in place. Regardless of what's powering your car, you've still got too feel good?