Sugar-Powered Cars

Pranksters put sugar in gas tanks to foul engines and halt cars in their tracks. But a Virginia Tech scientist is developing a way to run cars on sugar.

Y.-H. Percival Zhang's "sweet engine" runs on hydrogen made from starch, a clean-burning and potentially renewable alternative to fossil fuels.

Although hydrogen fuel cells are much more efficient than combustion engines, hydrogen is difficult to transport, store, and distribute – as well as expensive to produce. But Professor Zhang's method, which he presented April 9 at the national meeting of the American Chemical Society in New Orleans, circumvents the need for transportation and storage by turning sugar into fuel in the car on an as-needed basis.

It produces three times more hydrogen than current anaerobic fermentation methods. "This is the highest energy efficiency in the world," says Zhang, an assistant professor at Virginia Tech in Blacksburg, Va.

The secret? A stew of naturally occurring enzymes that, at 86 degrees F., create hydrogen and CO2 from a water-sugar mixture. The process could be market-ready in 5 to 10 years, says Zhang.