Photovoltaics is a key part in the renewable energy mix, and the technology is advancing daily. As a result, the cost of solar power is falling and new concepts are being developed for generating electricity in the future. One of the largest exhibitions for the solar industry, Intersolar Europe in Munich, starts on June 8th.
Faced with the environmental challenges that go hand in hand with supplying energy to an increasing global population, numerous incentive programs across the globe have emerged for developing renewable energy – most recently in India and China for example. And while the German government is paying lip service to a transition towards renewable energy, the feed-in tariff is falling. Therefore, researchers and industry are working against the clock to achieve grid parity – the point at which electricity from photovoltaic installations can be sold at a competitive price.
The rise in solar module efficiency is particularly encouraging regarding improving the performance of solar installations. In February, researchers at Freiburg’s Fraunhofer Institute for Solar Energy Systems ISE posted a new record for the efficiency of large-area, easy-to-manufacture silicon solar cells, over 19% – these cells could soon emerge on the market.
Researchers are pursuing different avenues to increase solar cell efficiency. Selecting optimal silicon material and developing new innovative production methods and technologies, both play their role in boosting efficiency. Such methods include improving emitters which collect the electric charge carriers. This was also the approach adopted by researchers at Fraunhofer ISE, who developed an aluminium-doped emitter for their module. Nanotechnology and pioneering laser processing techniques, used for example in optimizing the rear surface structure of the solar cell, are also paving the way for innovative and efficient systems.
Over the last 20 years some technological advances have occurred in photovoltaics. In 1989, the world record for the efficiency of multicrystalline silicon solar cells stood at 14.5%. In 2004, this rose to 17.7% and the 20% mark is already in sight for 2011. Developments in this field are first and foremost owed to improved production methods. For example, improved silicon crystallization processes in modern plants can raise module efficiency by at least 0.4% alone.
Well, the show might be worth a peek…