Secrets of the new Toyota Prius

I was honoured to speak with the chief engineer of the new Toyota Prius, Akihiko Otsuka, at the Geneva Motor Show recently. Honoured, because the young dude is quite a guy.

Oozing enthusiasm for the Prius, his groundedness and sheer enthusiasm wowed me. We’re close in age, he and I, and I really felt how ‘here and now’ he is. Think everything that’s dynamic and invigorating about modern Japan, for an idea of his approach.

This whirlwind of ideas shows in the new car, which really is quite something. Official fuel economy of the current one doesn’t always carry through to reality, I said. Unbowed, he admitted so – a key target of the new car was to improve on this.

He told his team to benchmark against the Volkswagen Golf 1.9 TDI – not the default 2.0 TDI, which is a fair bit less efficient. Quite a challenge, as I know how economical that engine can be. But Otsuka ‘beat it’.

A new approach to body design helped here – he allowed the aerodynamic engineers to work with clay models, ‘despite the expense’. This is unheard of in the car industry, where stylists normally hold sway. But, getting aerodynamics engineers so closely involved in the shape means the drag factor is a startling 0.25. An old Mini, by way of comparison, is 0.56….

However, while the hybrid gear is the big deal, he admits that this contributes only half to the overall 14 percent economy improvement. The other 7 percent?

‘Low rolling resistance tyres, aerodynamics and other energy improvement methods.’ The same, in other words, as employed on a VW BlueMotion, Volvo DRIVe, Ford ECOnetic, SEAT Ecomotive…

This fact brings home the law of diminishing returns. And the scale of the challenge car makers face in making cars continually more green.

I have an absolute mass of information from the discussion, which I’m using to write a piece for Automotive Engineer magazine. Overall, though, meeting Otsuka-san was quite something. In a month or so’s time, we’ll be finding out if his car is as good.