MAZDA is moving further down the hydrogen road, based on its eye-catching RX Hydrogen RE coupe revealed at the Tokyo motor show last week.
So confident is the Hiroshima-based car-maker in the hydrogen RX-8 that it plans to start leasing cars to government agencies in Japan next June from less-than $US10,000 ($A13,300) a month.
The latest RX hydrogen car, known as the H2RE, adapts its rotary-engine to burn either hydrogen or gasoline - at the touch of a button.
The dual-fuel engine develops 154kW/222Nm running on petrol or 81kW/120Nm on hydrogen and its applications in the rotary engine is relatively straightforward.
The test vehicle delivers good performance with no loss of interior space for four adults as the high-pressure hydrogen tank is mounted in the boot.
Mazda claims that because the engine switches to petrol once the hydrogen tank runs dry – currently limited to around 100km - drivers can rest easy about refuelling.
To boost both the petrol and hydrogen options, the car also adds electric motors and regenerative brakes common to petrol-electric hybrids.
Mazda also believes that the technology has an edge over fuel cells, which generate electricity from a chemical reaction between hydrogen and oxygen.
Although fuel cells produce no harmful emissions, the technology is not expected to be widely available for another 10 years.
The hydrogen rotary emits no CO2 and almost no NOx.
Also, because it uses conventional engine parts and manufacturing processes, Mazda says it can be manufactured at low cost, and the company anticipates high levels of built-in reliability.