Emissions, Renewables

Nanotechnology solar cells twice as efficient

24 May 2005 – Researchers at the US Department of Energy’s National Renewable Energy Laboratory have shown that nanotechnology could greatly increase the amount of electricity produced by solar cells.

The NREL team found that tiny ‘nanocrystals’, also known as ‘quantum dots’, produce as many as three electrons from one high energy photon of sunlight. This is compared to the one electron at most that gets converted with the current available solar cells, with the rest lost as heat.

Research team leader, Arthur Nozik, said: “We have shown that solar cells based on quantum dots theoretically could convert more than 65 per cent of the sun’s energy into electricity, approximately doubling the efficiency of solar cells.”

The most efficient cells available today convert approximately 33 per cent of the sun’s light into electricity.

Nozik first pioneered the project in 2000 when he predicted that quantum dots could increase the efficiency of solar cells, through a process termed ‘multiple exciton generation.’