SOLAR

Unidym's transparent conductive films and innovative CNT materials offer compelling cost and performance benefits to next generation solar cells.

The photovoltaic market is driven primarily by rising fossil fuel prices and concerns about global warming and national security. At present, the market is dominated by crystalline silicon cells. However, despite many years of research, this type of cell has yet to hit the cost and performance targets necessary to displace fossil fuels.

A new generation of solar cells, with the potential for a substantially lower cost structure than silicon, could close this performance gap and dramatically increase the size of the solar market. Termed thin-film cells, because of their use of ultra thin layers of light absorbing materials (as compared to the thick and correspondingly expensive wafers used in silicon cells), these next generation cells are the focus of hundreds of companies, thousands of researchers, and billions of public and private dollars. Much of this effort is going into the development of cells that can be produced using high volume roll-to-roll production techniques similar to those used to produce photographic film.

All of these thin film approaches rely on a transparent conductive film of material (or transparent electrode) to collect the current generated by the conversion of sunlight to electricity. At present, these films are created by time consuming, vacuum-based deposition of expensive metal oxides. Unidym believes its CNT films could offer a lower cost solution that is far more compatible with high volume production techniques. Unlike metal oxide films, Unidym's CNT films can be deposited with high volume roll to roll processes. In addition, Unidym's films are far more mechanically robust than metal oxide films which could substantially benefit yield. Unidym is currently working with a number of thin film solar manufacturers to incorporate its CNT technology into various thin film lines.

Beyond just providing a better transparent electrode, specialty materials developed by Unidym have a compelling role to play in enhancing the efficiency at which thin film cells convert light to electricity. For example, in dye-sensitized cells, CNTs can substantially enhance the conversion efficiency by providing pathways for the current generated by the conversion of sunlight to reach the cell's electrodes. Similiarly, in organic photovoltaics, functionalized fullerenes substantially enhance current efficiency. Unidym controls fundamental patents on functionalized fullerenes.

Unidym's technology has a powerful role to play in the Clean Technology revolution and is eager in exploring potential applications, collaborations, and licenses with interested companies.