Mazda pushes hydrogen Mazda displayed their toy-like HR-X show car at the Los Angles Auto Show, but made a more serious pitch for the fuel propelling the little bubble car -- hydrogen.
Hydrogen burns as cleanly as anything, producing only water and a few oxides of nitrogen -- which can be controlled both through lean-burn technology and reducing catalysts. Theoretically, it's possible to produce a hydrogen-fueled car that would meet -- as close as any combustion engine can -- "zero-emissions" standards. But in the real world, hydrogen has had a few problems.
First, hydrogen is subject to preignition. A conventional piston engine converted to hydrogen use tends to light off its incoming charge on hot exhaust valves or spark plugs. Second, hydrogen gas is very flamable, and hydrogen storage tanks buried inside cars can bring to mind pictures of the flaming Hindenburg -- the hydrogen-filled dirigible graphically demonstrated the gas's flamability.
Mazda claims to have solved both problems. The HR-X is powered by one of Mazda's Wankel engines, which neatly sidestep the hot-spot problem by having separate areas for mixture induction and combustion. Second, the HR-X uses a metal-hydride storage system, in which hydrogen gas would be bound to a metal for storage, much like oxygen binds to steel to make rust. A heater in the storage tank would free the hydrogen.
At a press conference at the L.A. Show, Mazda officials offered to share their hydrogen technology with other auto companies. Mazda's director of Product Planning and Research, Jack Stavana, said that only a cooperative effort could produce the infrastructure required to make hydrogen-fueled vehicles practical.