Complete Report - University of New South Wales

ARCPHOTOVOLTAICSCENTRE OFEXCELLENCE2010/11ANNUAL REPORT1. DIRECTORS’REPORTPhotovoltaics involves the direct conversion of light, normally sunlight, into electricitywhen falling upon devices known as solar cells. Silicon is the most common materialused to make these photovoltaic cells, similarly to its key role in microelectronics.The Australian Research Council (ARC) PhotovoltaicsCentre of Excellence commenced at the Universityof New South Wales (UNSW) on 13th June, 2003with funding initially until 31st December 2007.Upon review in 2005 and 2006, this funding wasextended until 31 st December 2010. Criteria forsuch extension included “progress of the Centretowards becoming independent of the ARC Centresof Excellence Scheme for funding”. With the rapidgrowth of the photovoltaics industry since theCentre’s commencement and the Centre’s strongand seminal links to this industry, the Centre wasclearly in a much stronger position for independentoperation beyond 2010 than many others in itsfunding cohort. Accordingly, while remaining underthe ARC Centres of Excellence umbrella beyond2010 in recognition of the quality of its research,the Centre will now be dependent upon industryrelatedfunding for research with near-termoutcomes and upon more academically-orientatedARC and international schemes for its longtermresearch.The Centre‘s mission remains to advance siliconphotovoltaic research on three separate fronts, aswell as to apply these advances to the related fieldof silicon photonics. The educational activities of theformer Key Centre for Photovoltaic Engineering arealso integrated into the Centre.Over the period of funding, photovoltaics hasbecome the world’s most rapidly growingenergy source, with markets increasing at acompounded rate of above 40%/year over thisperiod. The electricity generating capacity of newphotovoltaic product installed in 2006 exceedednew nuclear power capacity for the first time, withthe gap widening every year since. In Germany,photovoltaics has been the largest source of newelectricity generating capacity for each of thelast four years and became the second largestsuch source across Europe in 2010, ahead of windgenerators and behind only gas turbines. Reducingprices, at least partly traceable to past Centreinitiatives, means the technology is reaching “retailgrid parity”, where the cost of electricity generatedusing photovoltaics can compete at the point ofuse with normal retail electricity prices in manyparts of the world. This is expected to lead to aperiod of self-sustaining growth with photovoltaicspositioned to become one of the world’s majorindustries of the 21 st century. Even in Sydney where“cheap” electricity is supplied by power stationsbuilt on coal fields, photovoltaics is coming closeto being competitive with retail electricity priceswithout subsidies.Most present photovoltaic sales are of “firstgeneration”solar cells made from silicon wafers,similar to the wafers used in microelectronics.The Centre’s world-leadership with these “firstgeneration”devices, with international recordsfor the highest-performing silicon cells in mostmajor categories (including the outright highestperformingcells and modules) was recentlyextended with the demonstration of the first 25%efficient silicon solar cell. First-generation Centreresearch addresses the dual challenges of reducingcost and further improving efficiency. The rapidgrowth of the industry is generating widespreadinterest in ongoing innovations of the Centre’sfirst generation technology with several distincttechnologies now in large-scale production andadditional licences signed during 2010.Silicon is quite brittle so silicon wafers have to bereasonably thick, a fraction of a millimetre, to besufficiently rugged for processing into solar cellswith reasonable yield. Without this mechanicalconstraint, silicon would perform well even if verythin, even 100 times thinner than present wafers.Centre researchers have pioneered an approachwhere very thin silicon layers are deposited directlyonto a sheet of glass with the glass providingthe required mechanical strength. This “secondgeneration”approach gives enormous potential costsavings. Not only are the costly processes involvedin making wafers no longer required, but also thereis an enormous saving in silicon material. Cells alsocan be made more quickly over the entire area oflarge glass sheets. The Centre is at the forefrontof international research with such “secondgeneration”,silicon based approaches, with thefirst commercial product from “spin-off”, CSG Solar,2