Prius to evolve its breed

TOYOTA has all but confirmed its third-generation Prius hybrid will get more body variants than the current single five-door hatch, as well as limited production of a plug-in version.

However, Australians will not be able to buy anything other than the regular petrol-electric hybrid Prius III when it is released in July this year.

According to Akihiko Otsuka, chief engineer for the product-planning department at Toyota Motor Corporation, sharper looks, improved driveability and decreased costs should result in a significant increase in worldwide sales.

To that end, more than 1000 patents have been sought by Toyota as it renews about 90 per cent of the petrol-electric drivetrain.

Speaking to GoAuto at the 2008 North American International Auto Show (NAIAS) in Detroit – venue for the unveiling of the third-generation model – the Prius III’s chief engineer confirmed there would be different body styles, but would not comment on what these might be.

“In the future, it is possible,” Mr Otsuka saidd.

Widespread speculation suggests a more formally designed four-door sedan and a youth-baiting two-door coupe may eventually be on the cards – with the latter serving as a replacement for the long-dead Celica sporty car in much the same way as Honda’s forthcoming Insight-based CR-Z is likely to fill in the old Integra’s shoes.

Aiding the plans for body style expansions is the fact that the Prius III is built on Toyota’s modular MC platform that underpins everything from the Corolla to the Camry and Tarago. This should allow for much greater design diversification for the iconic hybrid.

Mr Otsuka said the Lexus HS 250h model that was also unveiled at the Detroit show shared the same basic hybrid system and included many of the aerodynamic and packaging advances made by the Prius III.

However, they were developed as separate models so Lexus designers and engineers could concentrate on the luxury-car brand values expected from a Lexus. This included a bigger, 2.4-litre engine instead of the new Prius’ 1.8-litre Atkinson cycle petrol-electric hybrid system that is also expected to debut in the next-generation Toyota Camry Hybrid in 2011.

Not offering the larger of the two engines in the Prius helped keep development costs down.

Mr Otsuka politely avoided revealing how much cheaper the new Prius would be to build compared to the old one.

The upcoming Prius III Plug-In will use all-new lithium-ion batteries instead of the tried-and-tested nickel-metal hydride packs used since the nameplate was introduced in Japan at the end of 1997.

Mr Otsuka said trials – involving about 500 vehicles to be leased to fleet companies and government agencies later in the year in Japan and North America – should help decide how and when “regular” petrol-electric hybrid Prius could switch to the more experimental lithium-ion batteries.

Running in purely electric vehicle mode, the Prius III Plug-In should have a range of 16km before the petrol engine kicks in.

“The range is much better than it was before,” Mr Otsuka said. “It depends on the battery condition.

“In the future capacity will increase within the same size volume (of today’s batteries).” Toyota says the price premium would be about $5000 to $5500 over the regular Prius.

Customers will also be able to choose a number of new-to-Prius options such as a solar sunroof, pre-collision safety devices and LED light emitting diode headlights. These are expected to increase the showroom appeal of the model as Toyota aims to grow the number of annual sales each year.

“We have to expand the number of customers,” Mr Otsuka said.

“Currently there are over seven million new-car sales every year, but only 400,000 customers buy our Prius.” Asked what he is most proud of in the latest Prius, Mr Otsuka’s reply was instant and unequivocal: “The MPG (miles per gallon) and environmental performance, for sure.”