Twenty years ago Lexus debuted its first cars, the LS 400 and ES 250, at the North American International Auto Show (NAIAS) in Detroit. At this year's NAIAS, the company celebrated reaching the two-decade mark by announcing the launch of its first dedicated luxury hybrid, the 2010 HS 250h.
"Did you know that more than 60 percent of entry-luxury car buyers would have considered buying a hybrid if one had been available?" asked Mark Templin, Lexus Group Vice President and General Manager. "They also want a car that is kinder to the environment with outstanding gas mileage and low emissions, as well as one that offers advanced features, the latest electronics, and one that delivers exceptional comfort."
Slotted to fit between its IS and ES models, Lexus believes the HS 250h will fulfill the wants of new and first-time buyers in the luxury segment, especially those looking for a vehicle with the benefits a hybrid affords—namely improved mileage and lower emissions.
"The HS is a dedicated hybrid, it's not sold with any other powertrain," Templin said. "While EPA numbers have not been finalized, we expect it will offer the best combined mpg of any luxury vehicle in the U.S. In fact, its city mpg should be higher than the two-passenger Smart micro car. The HS is the first Lexus equipped with a four-cylinder 2.4-L Atkinson-cycle engine that produces 187 horsepower."
The hybrid's Atkinson-cycle engine features the company's VVT-i system, which allows the expansion/power stroke to be longer than the compression stroke so that combustion energy can be more effectively used for production of engine power.
According to Lexus, the HS 250h sedan’s expected fuel efficiency will be more than 30% better than the most fuel-efficient model currently in the company's lineup, while earning a SULEV emissions rating and using regular 87-octane gasoline. Among the features adopted in the 2.4-L four-cylinder engine are cooling piston oil jets, an optimized balance shaft rate for improved NVH, and a hot-air venting system mounted behind the radiator.
Overall efficiency is also heavily stressed in the HS 250h. The vehicle includes an exhaust heat recovery system designed to reduce engine warm-up time, a feature that allows the engine to stop earlier, more often, and for longer periods of time. The vehicle's windshield features IR reduction properties to help keep the interior cool, serving to decrease the amount of air conditioning needed to lower cabin temperature. And power-saving LED headlamps contribute to improved fuel efficiency and emissions on the HS.
As with most of today's hybrids, boasting improved mpg ratings isn't enough to cement your reputation as being eco-minded. So, as a result, the HS 250h makes extensive use of plant-based, carbon-neutral “Ecological Plastics” or bio-plastics in specific interior areas. According to Lexus, Ecological Plastic emits less carbon dioxide during a product’s life cycle than plastic made solely from petroleum. Lexus leveraged these materials for use in the luggage-trim upholstery, cowl-side trim, door scuff plate, tool box area, floor-finish plate, seat cushions, and the package tray behind the rear seats. About 30% of the interior and luggage area is covered with Ecological Plastic.
The HS chassis features a MacPherson strut front suspension and double-wishbone rear suspension. Coil springs, antiroll bars, and shock-absorber rebound springs are used front and rear. The rack-and-pinion steering system features a brushless electric power steering (EPS) motor on the steering column for a reduction in harsh feedback and better emissions by not draining engine power like conventional hydraulic systems.
Rounding out the HS are a host of additional technologies: LED headup display, the Lexus Pre-Collision system, adaptive cruise control, a wide-view front monitor to aid in parking, and the Lexus Enform and Safety Connect telematics system.