Dye could hold key to solar power
Dye could hold key to solar power
2008-07-11Newsfeed
An organic dye which traps light inside an ordinary pane of glass could hold the key to harvesting sunlight for electricity production, according to a paper in the Science journal.
An organic dye which traps light inside an ordinary pane of glass could hold the key to harvesting sunlight for electricity production, according to a paper in the Science journal.
The US-developed technology channels the light to photovoltaic cells on the outside of the glass where it could turn up to 20% of incident light into electricity at a fraction of a cost currently achievable.
Instead of requiring an expensive collecting optic to track the course of the sun and direct light on to small cells, the dye molecules absorb a wide range of wavelengths which they then emit at a longer wavelength.
Total internal reflection then traps the light within the glass and guides it to the photovoltaic cells which efficiently convert the longer wavelength light into electricity.
MIT electrical engineer Marc Baldo developed new generation dyes which absorb a wider range of light than was possible when the technology was first tested in the 1970s. The MIT team also employed two layers of dye which absorb different frequencies.
The prototype's power conversion is estimated to be around 6.8% efficient, about the same as commercial cells made from amorphous silicon. However various improvements could make it capable of an efficiency of more than 20%.
Copyright © The Press Association 2008
