New Breakthrough in Photovoltaic solar cell efficiency

Researchers from Helmholtz Centre Berlin for Materials and Energy and the University of Sydney, with Australian Solar Institute support, have achieved a record breaking 40 per cent efficiency in the output from crystalline silicon solar cells. Previously, only up to about 33 per cent of energy could be harvested from normal amorphous crystalline silicon solar cells.

Associate Professor Tim Schmidt from Sydney University's School of Chemistry has been researching improving solar cell efficiency using the upconversion technique, a process which harvests the part of the solar spectrum currently unused by solar cells, and eliminates the need for costly redevelopment of solar cells.


"We are able to boost efficiency by forcing two energy-poor red photons in the cell to join and make one energy-rich yellow photon that can capture light, which is then turned into electricity," Associate Professor Schmidt said. "We now have a benchmark for the performance of an upconverting solar cell. We need to improve this several times, but the pathway is now clear."

You can read more on the upconversion process at the Australian Solar Institute website. The Australian Solar Institute provided $500,000 funding for the $1.5 million project from it's $150 million commitment by the Australian Government to support the development of photovoltaic and concentrating solar power technologies in Australia.

Australian Solar Institute Executive Director Mark Twidell said this is a great example of successful collaboration between leading Australian and German solar researchers.

"Together, Australia and Germany can accelerate the pace of commercialisation of solar technologies and drive down the cost of solar electricity," Mr Twidell said. "That’s why the Australian Solar Institute is supporting collaboration between the two countries through the Australia-Germany Collaborative Solar Research and Development Program."

An increase in efficiency in solar panels will again low the cost per unit of energy of solar photovoltaic power. Now it is just a matter of refining the process outlined in the scientific paper - Improving the light-harvesting of amorphous silicon solar cells with photochemical upconversion (abstract) - and incorporating the refinements at minimum cost in the solar panel production process.

Sources:

• Media release from University of Sydney, 19 April 2012 - Ray of light: Breakthrough in solar cell efficiency
  
• Yuen Yap Cheng , Burkhard Fückel , Rowan W. MacQueen , Tony Khoury , Raphaël G. C. R. Clady , Tim F. Schulze , N. J. Ekins-Daukes , Maxwell J. Crossley , Bernd Stannowski , Klaus Lips and Timothy W. Schmidt, Energy and Environment, 9 February 2012 - Improving the light-harvesting of amorphous silicon solar cells with photochemical upconversion (abstract) DOI: 10.1039/C2EE21136J
  
• Australian Solar Institute - upconversion process factsheet