Toyota Blog:

Katsuhiko Hirose is a man who has spent much of his working life looking into the future. He originally trained as a physicist, spending a year in the UK as a student and was involved in researching Nuclear Fusion. “The problem with that,” says Hirose “is that it was all too far into the future.”
 After that, he worked for Toyota on advanced engine research and had a spell liaising with the European Union on energy issues. He returned to Toyota, working on the development of the Prius hybrid, firstly on economy and emissions and then on the building and global distribution of what has become the world’s most successful hybrid car. Hirose points at his lapel badge and suggests proudly, but with underlying Japanese modesty, that he is known at Toyota as ‘Mr Hybrid Synergy Drive’.
 Today, the description of his job on his Toyota business runs to six lines, but it is probably easiest to call him Mr Hydrogen – Hirose is in charge of Toyota’s advanced research into hydrogen-powered cars. Hydrogen-powered cars have been under development by Toyota for at least two decades. The first concept version was based on a RAV4 and unveiled in 1997.
 In simple terms, Hydrogen power cars are propelled by electric motors. The electricity is generated inside the car by pushing Hydrogen gas through what’s called a fuel cell. The fuel cell splits the hydrogen into electricity and water: the electricity powers the motors and the only waste product from the exhaust pipe is the water.
 It sounds like an ideal, environmentally-friendly, alternative to fossil fuels. Hirose shows us Toyota research which suggests Hydrogen fuel-cell vehicles have an efficiency of 36 percent, compared to 24 percent for battery-powered vehicles and 28 percent for vehicles powered by compressed natural gas.