Feathered fuel tank soaks up hydrogen

Posted by jbrugger June 26, 2009 20:43PM

The gas tank of the future may be full of chicken feathers.

Engineers have discovered a way to store large amounts of hydrogen fuel using carbonized downy fluff, which could help pave the way to clean, green cars.

A practical hydrogen car has been elusive for decades. Before the announcement this week by University of Delaware engineers, a nonstop trip from Portland to Eugene in a hydrogen car would need a tank bigger than 100 gallons to store liquid or gaseous fuel, even under high pressure.

Treated chicken feathers work like a sponge. They soak up large amounts of hydrogen and hold it in a small space so the tank can be a conventional size and the fuel won't need to held under dangerously high pressures. Hydrogen creates only water vapor when it burns, unlike gasoline that emits carbon dioxide, a culprit in climate change.

"It's the most energy-rich material we have," says Roger Ely, an Oregon State University professor who specializes in hydrogen, "It's three times the energy content of gasoline on a pound-for-pound basis."

The problem is that this potent fuel is hard to squeeze into small spaces. "Once somebody cracks that nut, it's really going to help," Ely says.

Professor Richard Wool and graduate student Erman Senoz at the University of Delaware believe they may have found a solution.

"The question came up," Wool said, "of what to do with the six billion pounds of waste chicken feathers" produced every year. He experimented for years with various ways to use feathers and eventually wondered if they might store hydrogen.

Scientists have long known that hydrogen sticks well to carbon surfaces. Research has focused on tiny nanotubes, in which sheets of carbon are rolled into a compact space. The problem is nanotubes are expensive: A 20-gallon tank of them can cost more than $1 million.

Chicken feather fibers are mostly composed of keratin, a natural protein that forms strong, hollow tubes. The breakthrough moment came when researchers heated feathers to 700 degrees, causing a process called carbonization that created billions of tiny pores. They had found an ideal place to pack large amounts of hydrogen.

The new feather-based material can be produced at a small fraction of carbon nanotubes' cost. A 20-gallon feather-based tank would be about $100.

Don't expect to see hydrogen cars zipping along for another decade or more -- storage is just one of the problems. Production is another.

"There are no hydrogen wells," cautions Wool. A number of institutions, including Oregon State University, are looking at ways to convert sunlight to hydrogen.

Having pulled feathers from the landfill and turned them into fuel tanks, Wool sees "an infinite number of applications." Next up, watch for circuit boards, wind turbine blades and hurricane-proof roofs.

--Chris Spitzer;

Categories: Breaking News, Energy