QuantaSol Ltd, the independent designer and manufacturer of tuneable ultra high efficiency concentrated photovoltaic (CPV) solar cells, is moving into pilot production following a successful period of global customer sampling. QuantaSol's technology, based on adding multiple quantum wells to triple junction solar cells, greatly enhances photovoltaic conversion efficiency and offers system manufacturers a route to achieving breakthrough improvements in the performance of their CPV system whilst driving down the cost per kWh. The company has been sampling with customers across Europe, Asia and the USA for several months, and has worked closely with leading system vendors to enhance their systems by maximising energy harvest. Chris Shannon, QuantaSol's CEO commented, "Our technology has always been focused on achieving maximum efficiency and power output in real-world conditions, and this has been pivotal in moving forward from the lab stage towards production. Working with some of the best in the industry, we have been able to demonstrate genuine advantages in cost per kWh terms and this is a positive achievement for the solar industry." To date, QuantaSol has successfully accumulated an order book of more than 1MW of cells, and these will be delivered through the first half of 2011. QuantaSol is funded and backed by the Low Carbon Accelerator and Imperial Innovations, and its strain-balanced quantum-well solar cell (SB-QWSC) is believed to be the highest performing single-junction concentrator cell in the world with the potential to enhance multi-junction cells to record efficiencies very soon. Today's triple junction solar cells are the workhorse of a typical high concentration photovoltaic (HCPV) system. By splitting the solar spectrum into three colour ‘bands', each sub-cell in a triple junction device can convert the band of the spectrum to which it is sensitive at the best efficiency - this has led to world record efficiencies of >40% as compared to ~25% for traditional Silicon based technology. The materials used in today's leading triple-junction cells (InGaP, InGaAs, and Ge) are not the optimum combination of materials to maximise the potential efficiency of a triple-junction solar cell. QuantaSol can further enhance the efficiency of a triple-junction solar cell by using its Quantum Well technology to adjust, or ‘tune', the sub-cells of a triple junction cell. By doing this, efficiency increases are possible, since the cell can be tuned to absorb and convert more of the available light. Both triple-junction solar cells and optoelectronic devices containing quantum wells (for example, semiconductor LASERs) are technologies with a long heritage in both research and commercial production. QuantaSol is able to combine these two technologies to enhance the efficiency of today's market leading multi-junction solar cells, maintaining reliability and at a competitive cost to the CPV market in manufacture. Professor Barnham's research team at Imperial College has pioneered the application of nanostructures such as quantum wells and quantum dots for solar photovoltaics. The intellectual property generated through his research has resulted in a number of patents for the use of quantum wells in concentrator cells, the use of stress-balanced quantum wells in photovoltaic cells (SB-QWSC) and quantum dot light concentration (QDC). QuantaSol was formed in 2007 to commercialize the technology. It was quick to develop high efficiency single junction quantum well solar cells, and has now developed very high efficiency triple junction solar cells, enabling the market for this new, lower-cost renewable electricity generating technology. www.quantasol.com
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