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NATURAL gas could soon be generating electricity in millions of homes, thanks
to a revolutionary new fuel cell. The breakthrough allows the cells to run on
methane from the gas mains.

Fuel cells are advanced batteries that make electricity through chemical
reactions such as oxidation. This is cleaner and more efficient than burning
fossil fuel, but the technology has been held back partly because it鈥檚 difficult
to find a suitable fuel.

Until now hydrogen has been the front runner. The fuel cell converts it into
water and energy. But the hydrogen has to be made鈥攖ypically from a
hydrocarbon such as methane.

Conventional fuel cells cannot cope with hydrocarbons because the process
produces carbon which clogs up the cell鈥檚 nickel catalyst within minutes. But,
this week, Raymond Gorte and colleagues from the University of Pennsylvania in
Philadelphia have shown that using a copper and cerium oxide catalyst in the
fuel cell, instead of nickel, prevents carbon building up.

鈥淭his discovery is a winner,鈥� says Kevin Kendall of the University of Keele
chemistry department. Gorte sees his fuel cells powering clean cars, but Kendall
thinks the main application could lie elsewhere. 鈥淢illions of homeowners replace
their gas-fired central heating systems in Europe every year. Within five years
they could be installing a fuel cell that would run on natural gas,鈥� says
Kendall. This battery in the basement could generate enough electricity to run
the home as well as heating it, he says. 鈥淓very home could have a combined
heat-and-power plant running off mains gas.鈥�