From Nature Science Update.....it appears that this is the equivalent of a 'direct' hydrocarbon fuel cell (no reformer necessary), just as Ballard is working on a direct methanol fuel cell (DMFC). The obvious first difference, however, is that this one uses a SOFC instead of a PEMFC. Also notice, though, the comments about being able to possibly run this fuel cell on "on petrol and diesel" in the future.
Technology : Flameless Fuels
DAVID ADAM
If, as Shakespeare suggested, the world is a stage, then oil and gas are the pantomime villains: we may boo and hiss fossil fuels, but we love them really.
Enter, stage right, natural gas. Fed-up of playing the scoundrel, it offers to provide a new, clean source of power for computers, phones and even cars. Now three US chemical engineers write the first page of this unlikely drama in Nature1.
High-tech batteries called 'fuel cells' can release the energy that is locked inside fuel without burning it. This is cleaner and more efficient. They draw electric current from a chemical reaction between the fuel and oxygen in the air. Fuel cells usually use hydrogen, which is difficult to produce and dangerous to store. This makes them so expensive to run that at present they are only popular with spacecraft engineers.
Now Raymond J. Gorte and colleagues at the University of Pennslyvania, Philadelphia, announce technology that could bring these orbiting generators down to earth. They have made a fuel cell that uses natural gas (methane) and other fossil fuels. The only by-products are water and carbon dioxide.
Methane and its chemical cousins, ethane, toluene, butene and butane, are cheap and easy to come by. The fuel cell developed by Gorte's team turns all five into electricity. So far it churns out about a tenth of the power of hydrogen-fuelled alternatives. But the group is confident that this will improve.
"What we showed was more a demonstration of the concept than results for an optimized system," says Gorte. "I am sure that we can do much better. I don't believe that there are inherent limitations to our matching the performance of the best systems."
Like all batteries, fuel cells have positive and negative terminals. The negative terminal or 'cathode' of a fuel cell strips oxygen ions from the air. The positive, 'anode', terminal attracts the oxygen ions and combines them with fuel. This reaction frees electrons from the fuel, producing electricity. Current flows as long as this circuit stays intact.
Previous attempts to feed fuel cells with hydrocarbon fuels from oil and gas could not stop the electrical circuit from breaking. Soot builds up within minutes on the nickel-based anode. The anode in this new cell is made of a copper and ceramic mixture, which does not gather soot.
This is a real breakthrough, says Kevin Kendall, a chemist at Keele University, UK, "It's very exciting. They address the main problem of fuel cells: how to run them on real fuels." Fuel cells that work with methane could be adapted to run on petrol and diesel.
A ceramic core called the 'electrolyte' separates the two electrodes. Oxygen ions will only flow through the electrolyte at blistering temperatures, approaching 800 øC. The temperatures will fall as the technology improves, Gorte's team believes.
But there could be problems applying the technology on a larger scale, materials scientist Brian Steele of Imperial College, UK, points out. At high temperatures, he says, methane may react with stainless steel pipes used to supply the gas.
Kendall does not see this as a problem. "I think the real benefits of this technology are to small-scale, domestic systems. Power systems in cars, computers and mobile phones, for example," he says.
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