Canadian scientists have found a new way to generate electricity.

Larry Kostiuk and his colleagues at the University of Alberta made the discovery when they were investigating what happens when tap water is forced down tubes narrower than a tenth the thickness of a human hair.

This generated a small electric current -- about a nanoamp.

To produce more electricity, the team tried forcing water through a glass water filter with thousands of narrow channels lined up side by side.

"When we took a syringe of water and squeezed it through the filter, we got enough power to light a light bulb," the Guardian Web site quoted Kostiuk as saying. "The harder you push the syringe, the more volts you get."

When filled with water, positively charged ions in the tubes are washed away, leaving a negative charge on the surface. When water is then forced along the tube, the surface repels negatively charged ions in the water while positively charged ions are attracted down the tube. The result is a net flow of positively charged ions that sets up an electric current.

Kostiuk said the last time someone came up with a way of generating electricity was Michael Faraday in 1839.

The work was published in the Journal of Micromechanics and Microengineering on October 21.