Silicon Solar Cell Innovation

Scientists in the US have developed an innovative flexible solar cell production method incorporating silicon wires that removes 99 per cent of the material usually drawn upon to create standard photovoltaic panels.

Their ultimate goal is to produce ultra-thin cells that – to take one example – can be woven into products like clothing but, for the moment, their technology simply represents lower-cost photovoltaics that will be more straightforward to put in place.

Solar Cell Technology

Details of the scientists’ new solar cell technology appear in the current edition of the Nature Materials publication. The piece describes how the material uses traditional silicon which has been shaped into minute wires and sits in a vertical arrangement in the cell. The usual approach to silicon solar cells involves so-called “wafers” which can be up to 200 micrometres in thickness.

Here, the silicon wires are around 2 micrometres thick, and the space in between them allows light to bounce around, prior to absorption. The wires also mean the panels can take the form of thin film, capable of being distorted and rolled.

The research has involved scientists working at the California Institute of Technology.

“The idea is it would be lower cost and easier to work with by being more flexible than conventional silicon solar cells”, institute representative Michael Kelzenberg told news agency Reuters, adding: “It is potentially a route to bypass many of the costs associated with producing solar cells.”

Silicon Solar Panels

Commenting on the development, UK-based scientist Gianfranco Claudio told monthly magazine Chemistry World how using silicon wire solar panels seemed to offer another benefit, too. “The biggest limitation for conventional silicon is that it is blind in the infrared region of the spectrum and so this light available from the sun is not converted to photocurrent”, he said. “Silicon wires can capture the light from this region, potentially overcoming this inefficiency.”

Towards the end of 2009, Australian and German scientists announced that they had come up with a way of stacking printable solar cells and making them more energy efficient.