For the last decade or so, Toyota's Prius hybrid has been the go-to car for buyers wanting something a little more fuel efficient, a little greener than the norm.

While still immensely successful, today's Prius has more or less lost its unique selling point--a host of plug-in vehicles has taken away its crown as the most efficient car on sale.

Perhaps a new and more 'heart-racing' design will help the next model regain some of its shrinking green status, as that's what Toyota is planning for some of its less dramatic models.

Speaking to Driving (via Autoblog Green) at the Detroit Auto Show, Toyota executives suggested that models such as the Prius and Camry are set to become a little more exciting.

It's part of a wider plan to appease gearhead Toyota president Akio Toyoda, who wants even the brand's mainstream vehicles to have appeal beyond that of mere appliances--increasing appeal without sacrificing their more traditional values.

While a future Camry will still play it relatively safe, the Prius design has more room to maneuver--that's according to Kelly Blue Book's Jack Nerad.

Toyota can afford to push the Prius a little harder, since existing buyers are loyal to the name and "more likely to accept something different".

The familiar teardrop profile of the Prius is unlikely to change any time soon--it's as much a part of the car as the drivetrain and the name--but Toyota can afford to take more risks with the details.

We've seen some hints as to the Prius's next direction in recent concept vehicles like the FCV, which show that Toyota is taking a more daring approach to design in the future.

MORE: 2015 Toyota Prius: Next Hybrid Aims For 55 MPG, More Room, Better Handling

But more important even than styling is the way the next Prius goes about being efficient.

Tokuo Fukuichi, a Toyota senior managing officer says hybrids are already a "fundamental technology", and it puts the Prius in a difficult position. The new car has to feel futuristic and offer "best in the world" fuel economy.

Miss out on these goals, says Fukuichi, and the Prius is essentially pointless--since customers can now go to any number of other automakers if they want impressive fuel economy.

The 2015 Prius is expected to continue on previous versions' 10 percent economy improvement, suggesting combined economy of 55 mpg.

It'll also be lighter, roomier inside, and "lower in cost", as well as featuring a more powerful electric motor, a more sophisticated suspension setup and improving on safety kit.

A simpler dashboard, losing the familiar "flying buttress" layout, and a standard lithium-ion battery pack are also likely to feature.

We'll still have to wait several more months, perhaps into 2015, before we see the next-generation Prius in production form. But the car we see may well be more interesting to behold than before, as well as more efficient.


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