Scientists jump at shadows for energy

SINGAPORE－Scientists in Singapore are trying to perfect a new method of power generation driven by shadows, with the hope that it could help cities power themselves.

The shadow-effect energy generator being developed by the National University of Singapore has the potential to harness power like solar cells, but without needing open spaces with uninterrupted light. It needs both light and dark and also relies on light to shine on silicon to energize electrons. But, using panels that feature a thin layer of gold, silver, platinum or tungsten, the difference in light intensity drives electrons from lit areas toward the shade, creating electricity in the shaded areas.

"Our generator can be placed in areas to harvest obstructed light," says team leader Swee Ching Tan.

The tested panels are 6 square centimeters in size and capable of producing 0.25 volts, meaning about 20 are needed to power a light bulb or charge a cellphone.

The ideal environment for use would be cities, Tan says, where with skyscrapers, shadows are persistent.

Reuters