While Mazda continues to develop its fascinating gas/hydrogen-powered rotary RX-8 (it should be available in Japan in 2006), it showed something even more advanced at the 2005 Tokyo Motor Show, a rotary hybrid version of the latest Mazda 5.
In the nose of this 5, Mazda mounted the same bi-fuel, two-rotor hydrogen RENESIS as the impending RX-8--the first time it's been demonstrated in a front-drive application.
The rotary engine links to a Mazda-developed hybrid unit, which is also in the nose. There are two fuel tanks: gas beneath the rear seat (a battery array also resides there) and a hydrogen tank in the back, replacing the third row of seats.
In this way, the Mazda 5 can run either on hydrogen or gasoline--just like the dual-fuel RX-8--and you can switch between the two using a small button on the dash.
Mazda's idea with this alternatively powered 5 is to expand the range of models in which a hydrogen rotary potentially can be used, and this car is a better fit than the RX-8 for the bi-fuel hardware because of its larger size; the hydrogen tank fills up nearly all of the RX-8's small trunk.