Toyota today released a few more nuggets of information about the next, all-new generation of its Prius hybrid car.

The all-new Prius, to be released in 2015, is likely to continue each generation's 10-percent improvement on the fuel economy of its predecessor.

With the current Prius Liftback rated at 50 mpg combined, that would take the 2015 model to 55 mpg.

The news was released by Satoshi Ogiso, Toyota's chief engineer and the man in charge of developing the next range of Prius models.

He stressed the challenge of continuously improving efficiency as consumption falls to extremely low levels, and declined to specify a specific numeric target for the next Prius.

Ogiso has worked on Toyota hybrids since October 1993, when he was assigned as a young engineer to the G21 team that developed the first Prius released in 1997.

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Bigger inside, smaller outside

The new fourth-generation Prius will use an updated version of the company's Hybrid Synergy Drive.

It will feature a more efficient engine, more powerful electric motor-generators, and "advanced battery technology" with higher energy density (almost surely lithium-ion cells).

Inside, it will be roomier, within a "more compact package that is lighter in weight, and lower in cost."

2012 Toyota Prius Plug-In Drive - March 2011

2012 Toyota Prius Plug-In Drive - March 2011

It will be built on a shared component set called Toyota New Global Architecture, or NGA, with a lower center of gravity and a more rigid structure.

Though Ogiso did not say so, the updated hybrid is expected to switch to a trailing-arm rear suspension design, giving far better handling and roadholding than the current model.

And it will introduce unspecified "advanced safety technologies."

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More electric range for plug-in Prius

In addition, the next-generation Prius Plug-In Hybrid will be developed in parallel with the standard hybrid model.

"We have been listening very carefully to Prius [plug-in] owners over the past two years," Ogiso said, "and [we] are considering their request for additional all-electric range."

Moreover, Toyota is developing a new wireless inductive charging system that eliminates the need for a charging cable.

The company will begin verification of that system in Japan, Europe, and the U.S. next year.

Rife with rumors

Rumors about the 2015 Prius have circulated for more than a year now. Among the features it's thought to contain are:

  • A design somewhat different to the current wedge shape
  • A lithium-ion battery pack
  • An interior without the high "flying buttress" console for more accessible storage between the seats

According to persistent rumors, it may even offer all-wheel drive

2012 Toyota Prius Plug-In Hybrid, production version road test, San Diego, CA, Jan 2012

2012 Toyota Prius Plug-In Hybrid, production version road test, San Diego, CA, Jan 2012

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Although it hasn't named a location yet, Toyota confirmed last year that it plans to build the next Prius in the U.S.

Then, back in May, spy shots of Prius prototypes under test emerged, prompting the last round of rumors.

The Prius is Toyota's flagship model, the "halo car" that has brought the entire brand an image of environmental responsibility.

The company has built more than 3 million Prius models, and more than 5 million Toyota and Lexus hybrids of all models, since the first Prius was launched on the Japanese market in 1997.

Today's Prius lineup comprises the classic Prius Liftback, the Prius V wagon, the Prius C subcompact, and the Prius Plug-In Hybrid.

All but the Prius V are rated at 50 mpg combined by the EPA.

Toyota provided airfare, lodging, and meals to enable High Gear Media to attend the Toyota Hybrid World Tour event and bring you this first-person report.


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