University of New South Wales develops technique to improve use of low-grade silicon for PV production

09 May 2013

On May 6th, 2013, the University of New South Wales (UNSW, Australia) announced that its solar engineers have developed an innovative method to improve the quality of low-grade silicon in order to improve the efficiency and reduce the cost of solar photovoltaic (PV) panels.

"This process will allow lower-quality silicon to outperform solar cells made from better-quality materials," stated Scientia Professor Stuart Wenham from the School of Photovoltaics and Renewable Energy Engineering at UNSW.

Solar cell efficiencies between 21% and 23% expected

The Researchers have discovered a mechanism to control hydrogen atoms so they can better correct deficiencies in silicon – by far the most expensive component used in the making of solar cells.

Currently, standard commercial silicon cells have a maximum efficiency of around 19%. The new technique, patented by UNSW researchers earlier this year, is expected to produce efficiencies between 21% and 23%, Wenham added.

Hydrogen atoms can exist in three ‘charge’ states – positive, neutral and negative. The charge state determines how well the hydrogen can move around the silicon and its reactivity, which is important to help correct the defects.

"We have seen a 10,000 times improvement in the mobility of the hydrogen and we can control the hydrogen so it chemically bonds to things like defects and contaminants, making these inactive," Wenham added.

The UNSW team currently has eight industry partners interested in commercializing the technology, and is also working with manufacturing equipment companies to implement the new capabilities.

The project, which has been supported by the Australian Renewable Energy Agency, is expected to be completed in 2016.