Air Date: Week of November 21, 2003

Living on Earth's Cynthia Graber reports on a new, more efficient fuel cell.

Transcript

GELLERMAN: Just ahead: the health costs when free trade comes trucking through your neighborhood. And, details on how to win an African safari for two. First, this Note on Emerging Science from Cynthia Graber.

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GRABER: Hydrogen fuel cells offer the promise of nearly pollution free driving. But in today’s demonstration vehicles, fuel cells require water to move a charge, or ions, across a membrane to create energy. And there are some problems with that system. It can only operate in a temperature range from about 75 to 175 degrees Fahrenheit. These relatively low temperatures mean that the engineers need to design large radiators which lead to heavier cars and a less efficient system. On top of that, designers have to worry about how to deal with the water that builds up on one side of the membrane and is depleted on the other.

Now, some scientists at CalTech believe they have an answer. They are developing a membrane made of solid acids that allow ions to flow across it without using water. This means a more efficient fuel cell,and allows engineers to build smaller, lighter systems. One added benefit is that in these solid fuel cells, methanol could be used for a fuel instead of hydrogen.

Methanol is an alcohol fuel easily made from renewable resources. It would also be easier to pump and store than hydrogen. The researchers recently built these solid acid fuel cell prototypes and successfully ran them on both hydrogen and on methanol for dozens of hours.

That’s this week’s Note on Emerging Science, I’m Cynthia Graber.

GELLERMAN: And you're listening to Living on Earth.

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